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Injury Assessment of Sea Turtles Utilizing the Neritic Zone of the Southeastern United States

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Title:
Injury Assessment of Sea Turtles Utilizing the Neritic Zone of the Southeastern United States
Creator:
NOREM, APRIL D. ( Author, Primary )
Copyright Date:
2008

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Subjects / Keywords:
Amputation ( jstor )
Boats ( jstor )
Female animals ( jstor )
Juveniles ( jstor )
Loggerhead turtles ( jstor )
Physical trauma ( jstor )
Propellers ( jstor )
Sea turtles ( jstor )
Sharks ( jstor )
Turtles ( jstor )

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University of Florida
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University of Florida
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Copyright April D. Norem. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Embargo Date:
12/31/2006
Resource Identifier:
496174561 ( OCLC )

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INJURY ASSESSMENT OF SEA TURTLES UTILIZING THE NERITIC ZONE OF THE SOUTHEASTERN UNITED STATES By APRIL D. NOREM A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2005

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Copyright 2005 By April D. Norem

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To my parents, Jim W. Norem and Kay J. Hall.

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iv ACKNOWLEDGMENTS This project would not have been possi ble without the help and support from numerous people. First and foremost, I am gratef ul to the sea turtle research staff at the St. Lucie Nuclear Power Plant (SLNPP) for th eir dedication to sea turtle research and conservation. Specifically, my gratitude goes to Mike Bresette, Ri ck Herren, and Dave Singewald for all of their hard work. I am also appreciative of th e travel support from Florida Power & Light (FP&L). I would also like to express my appreci ation to my committee chair, Raymond R. Carthy. I am extremely grateful for his support in allowing me to pursue my own research interests and for several valuable discussions . I also extend my gratitude to Elliott R. Jacobson for serving on my committee. His exper tise in the field of Veterinary Medicine was insightful. Many thanks to Meghan Brennen and Marinela Capanu of the IFAS Statistics Help Program at the University of Florida. I cer tainly enjoyed the exchange of turtle-life history information for sta tistical assistance. Finally, I would like to thank my friends and family for their endless support. Specifically, Elizabeth Martin and Aletris Neils made th e Florida Coop Unit a ‘warm’ place to work. More than I can express in wo rds, my parents, Jim W. Norem and Kay J. Hall, and my brother, Gage T. Norem, have my deepest gratitude. Without their continued love and support, I would not possess such fort itude in life. I am also

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v extremely grateful to my dogs, Horizon and Dusk, two fur balls that endured Florida’s heat and humidity.

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vi TABLE OF CONTENTS page ACKNOWLEDGMENTS.................................................................................................iv LIST OF TABLES.............................................................................................................ix LIST OF FIGURES...........................................................................................................xi ABSTRACT.....................................................................................................................xi ii CHAPTER 1 INTRODUCTI ON AND BACKGROUND.................................................................1 Introduction................................................................................................................... 1 Background...................................................................................................................2 Population Ecology...............................................................................................2 Vital Rates in Long-Lived Species........................................................................3 Threats to Sea Turtles............................................................................................4 Study Objectives...........................................................................................................5 2 SEA TURTLE INJURY IDENTIFICATION SYSTEM..............................................7 Introduction................................................................................................................... 7 Methods........................................................................................................................ 8 Study Area.............................................................................................................8 Study Site...............................................................................................................9 Intake system..................................................................................................9 Ocean intake structures..................................................................................9 Intake canal and discharge system...............................................................10 Barrier net implementation and modification program................................10 Procedures...........................................................................................................11 Sea turtle capture program...........................................................................11 Description and Discussion........................................................................................13 Sea Turtle Injury Identification System (STIIS).................................................13 Injury Types/Causes............................................................................................16 Flipper amputation.......................................................................................16 Barnacle........................................................................................................17 Shark-related................................................................................................17 Social interactions........................................................................................17

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vii Boat propeller...............................................................................................17 Fishing interactions......................................................................................18 Intake pipe....................................................................................................18 Oil/tar...........................................................................................................18 Unknown......................................................................................................18 3 ANTHROPOGENIC AND NONANTHROPOGENIC INJURY ANALYSES.......32 Background.................................................................................................................32 Non-anthropogenic Threats to Sea Turtles..........................................................32 Sharks...........................................................................................................32 Social interactions........................................................................................33 Barnacles......................................................................................................34 Anthropogenic Threats to Sea Turtles.................................................................34 Commercial and private boating..................................................................34 Marine debris................................................................................................36 Oil and tar pollution.....................................................................................37 Sea Turtle Life History Traits..............................................................................38 Flipper function............................................................................................38 Body region susceptibility............................................................................39 Methods......................................................................................................................40 Statistical Analysis..............................................................................................40 Injury analysis: May through December 2000.............................................40 Boat propeller and flipper amputation analysis: May 2000 through July 2004..........................................................................................................40 Results........................................................................................................................ .42 May through December 2000 Captures...............................................................42 Anthropogenic Injuries........................................................................................44 Boat propeller strike.....................................................................................44 Tar................................................................................................................44 Fishing..........................................................................................................44 Non-Anthropogenic Injuries................................................................................44 Shark.............................................................................................................44 Social interactions........................................................................................45 Barnacle........................................................................................................46 Summary of Missing Regions of the Body.........................................................46 May 2000 through July 2004 Boat Propeller Strikes and Flipper Amputations.46 Flipper amputations (equal to or greater than half)......................................47 Within-species analyses...............................................................................48 Location analyses.........................................................................................49 Boat propeller strikes...................................................................................49 Within-species analyses...............................................................................50 Location analyses.........................................................................................51 Conclusion..................................................................................................................52

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viii 4 INTAKE PIPE RELATED INJURIES.......................................................................71 Background.................................................................................................................71 Methods......................................................................................................................72 Time Period and Objectives................................................................................72 Statistical Analyses..............................................................................................74 Results........................................................................................................................ .74 May through July 2000 to 2005...........................................................................74 Fresh scrape body region analysis (May through July 2000, 2002, and 2004)...75 Conclusion..................................................................................................................76 5 SUMMARY AND C ONSERVATION SIGNIFICANCE.........................................85 APPENDIX A Flipper Amputations Ma y Through December 2000.................................................88 B Summary of Injury Results May Through December 2000.......................................89 LIST OF REFERENCES...................................................................................................92 BIOGRAPHICAL SKETCH.............................................................................................98

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ix LIST OF TABLES Table page 2-1 Categories of injury recency (fre sh, partially healed, and healed)...........................31 2-2 Shark-related injury criteria. Each criterion may be mutually exclusive.................31 3-1 Species, size range, mean standa rd deviation of the 448 individual turtles captured May through December 2000 at the SLNPP.............................................67 3-2 Overview of all injury causes found within each species May through December 2000........................................................................................................67 3-3 Injury type records (n=858) f ound on the 511 turtles cap tured May through December 2000........................................................................................................68 3-4 Injury location records (anatomical re gion) with and without intake pipe related injuries found on the 511 turtles captured May through December 2000................68 3-5 Flipper amputation results May th rough December 2000 (le ss than half, half, over half, and entire) within species ( Caretta caretta , Chelonia mydas , and Eretmochelys imbricata ) and sex class (male, female and unknown sex)...............69 3-6 Species, size range, mean standard deviation of 3,290 turtles captured at the....69 3-7 Percentage of turtles found with am putations within each life stage (adult, transitional, and juvenile) and sex category (male, female, and unknown).............69 3-8 Percentage of turtles found with boa t propeller strikes within each sex category (male, female and unknown)....................................................................................70 3-9 Percentage of turtles of each species found with boat propeller strikes within the anterior and posterior subregion of the carapace.....................................................70 4-1 Percentage of each size class with in each year (May through July, 2000 to 2005) found with fresh scrapes................................................................................83 4-2 Percentage of fresh scrapes within each severity class (superficial and deep) May through July, 2000, 2002, and 2004.................................................................84

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x A-1 All flipper amputations (less than half , half, over half, and en tire) within species ( Caretta caretta and Chelonia mydas ), size class, and sex class (male, female and unknown sex) May through December 2000 at the SLNPP..............................88 B-1 Summary of injury results for known causes (barnacle, tar, fishing, social, boat propeller strike, and shark) May through December 2000 at the SLNPP................89

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xi LIST OF FIGURES Figure page 2-1 St. Lucie Nuclear Po wer Plant located on Hutchinson Island, Florida, USA..........19 2-2 Aerial view of the St . Lucie Nuclear Power Plant a nd nearshore reef system.........20 2-3 Sea Turtle Injury Identification System (STIIS) developed by A.D.Norem............21 2-4 Flipper Amputations.................................................................................................22 2-5 Two deep barnacle depressions on the 3rd vertebral on the cara pace of a juvenile C. mydas (numerical region 2abcd)..........................................................................23 2-6 Shark-related injuries...............................................................................................24 2-7 Injuries resulting from soci al interactions among turtles.........................................25 2-8 Boat propeller injuries..............................................................................................26 2-9 Cracked carapace on C. caretta (numerical region 2cd).The cause of injury was classified as unknown...............................................................................................27 2-10 Fishing-related injuries.............................................................................................28 2-11 Fresh scrape injuries.................................................................................................29 2-12 Oil on the ventral side of C. caretta (numerical regions 3abcd, 4abcd, 5abcd, 6abcd, 7abcd, and 8).................................................................................................30 2-13 Symmetrical non-descriptiv e injuries on the plastron of C. caretta (numerical subregion 7ab). The cause of injury was unknown..................................................30 3-1 Species ( Caretta caretta , Chelonia mydas , and Eretmochelys imbricata ) and sex composition (male, female and unknown se x category) of the individual turtles (n=448) captured May through December 2000 at the SLNPP...............................59 3-2 Total number of recaptures and new recruits for Caretta caretta (CC ) , Chelonia mydas (CM), and Eretmochelys imbricata (EI) May through December 2000.......60

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xii 3-3 Size class distribution of Caretta caretta (n=243), Chelonia mydas (n=203) and Eretmochelys imbricata (n=2) captured May through December 2000 at the SLNPP......................................................................................................................61 3-4 Proportion of turtles (n=511, capture s and recaptures) found within each body condition (good, fair, poor, and dead) cap tured May through December 2000 at the SLNPP................................................................................................................62 3-5 Proportion of injury causes found on the 511 turtles cap tured May through December 2000. Individuals may have multiple injury causes................................63 3-6 Size class distribution of Caretta caretta (n=1875), Chelonia mydas (n=1386), Dermochelys coriacea (n=8), Eretmochelys imbricata (n=17), and Lepidochelys kempii (n=4) captured May 2000 through July 2004 at the SLNPP (includes recaptures)................................................................................................................64 3-7 Frequency of flipper amputations di vided by numerical regions (3, 4, 5, and 6) within Caretta caretta (males, females and unknown sex categories)....................65 3-8 Frequency of flipper amputations di vided by numerical regions (3, 4, 5, and 6) within Chelonia mydas (males, females and unknown sex categories)...................66 4-1 Percentage of each species Caretta caretta (CC), Chelonia mydas (CM), Dermochelys coriacea (DC), and Eretmochelys imbricata (EI) captured May through July 2000 to 2005........................................................................................79 4-2 Size class distribution for each year May through July 2000 to 2005.....................80 4-3 Proportion of turtles found with fr esh scrapes May through July, 2000 to 2005.....81 4-4 Fresh scrape occurrence within size class May through July, 2000 to 2005...........82 4-5 Proportion of fresh scrapes found within each body region May through July 2000 (n=185 records), 2002 (n=201 records), and 2004 (n=252 records)...............83

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xiii Abstract of Thesis Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science INJURY ASSESSMENT OF SEA TURTLES UTILIZING THE NERITIC ZONE OF THE SOUTHEASTERN UNITED STATES By April D. Norem December 2005 Chair: Raymond R. Carthy Major Department: Interdisciplinary Ecology Natural and anthropogenic factors regulate the long-term survival of sea turtles. To gain further understanding of the injury condition and possible effects of non-lethal injuries on sea turtles utilizing the neritic zone of the southeastern United States, a systematic Sea Turtle Injury Identification System (STIIS) was developed and applied to the turtles entrained at the St. Lucie Nu clear Power Plant (SLNPP). Physical cues (injuries) resulting from past interactions between turtles and the abiotic/biotic factors within their environment were quantified a nd statistically compared for the time period May 2000 through July 2005. Data were collected on anthropogenic (fishi ng, oil/tar, boat propeller strikes, and SLNPP intake pipes) and natura l sources (shark, social inte ractions among turtles, and barnacles). This information was compared am ong species, size class (life stage), and sex class. Unfortunately, the size class distributi on of turtles captured during the study period

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xiv limited analyses. Green turtles were predominan tly within the small juvenile size classes, whereas the loggerhead turtles were large ju venile/transitional and adult turtles. It was determined that within recent years, significantly more turtles incurred fresh scrapes while traveling through the intake pi pes at the SLNPP. An increase of fresh scrape records within the eye and head region is an indicato r of plant-related impacts to the sea turtles entrained at the SLNPP. Overall, the data suggests in creased fouling inside the intake pipes and supports cleaning of the intake pipes. The data suggests that significantly more loggerhead turtles are traumatized by boat propellers than green turtles. A dditional data should be collec ted to elucidate if this is a species and/or size class effect. Loggerhead tu rtles were traumatized significantly more within the posterior subregion 2a of th e carapace compared to green turtles (70.7% compared to 28.6%, respectively). No significant differences were found be tween the number of loggerhead and green turtles with flipper amputations. However, significant differences were found between life stages and sex clas s. The rear flippers accounted fo r 78% of the amputations found in green turtles. The front right flipper accounted for the highe st number (35%) of flipper amputations in loggerhead turtles. While, this was statistically non-s ignificant, there may be a biological significance. Overall, the data supported the idea that the types and causes of injury may vary across species, size class and sex class. The ST IIS created in this pr oject can be applied globally by researchers and volunteers across research and stranding projects assessing both live and dead turtles.

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1 CHAPTER 1 INTRODUCTION AND BACKGROUND Introduction Sea turtles exhibit slow gr owth and late sexual matu ration, traits typically found within long-lived wildlife species (Dennis et al. 1991). Unfortunate ly, such demographic factors make sea turtles partic ularly vulnerable to biotic a nd abiotic factors that could potentially decimate their populations (Zug et al. 2001). In order for resource managers to take the necessary steps in protecting sea tu rtles, basic biologi cal and ecological life history information must be collected a nd made available (Witzell et al. 2002; Witherington 2003). For example, it has become increasingly clear th at sea turtles face many threats in their marine environments, pa rticularly along migr atory routes, foraging grounds and nesting beaches. Clear identifica tion and quantification of such threats has been minimal due to the difficult nature of obtaining such information on a group of organisms that spend the majority of their lives in the sea. Since 1976, the St. Lucie Nuclear Power Plan t (SLNPP) has maintained a database of all sea turtles inadvertently captured at th e electric generating facility, which includes detailed injury records. This project utilized both new and historical data (May 2000 through July 2005) collected at the St. Lucie Power Plant to quantify primary types and causes of injuries, and to further iden tify regions of the body that may sustain significantly higher rates of inju ry (e.g., posterior versus ante rior regions of the carapace, front and rear flippers, and the head regi on). This was accomplished by studying physical injuries (e.g., wounds, oil, fishing line) left from past interact ions among turtles and

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2 abiotic/biotic factors. A primary objective of this project was to gain insight into many types of sea turtle species in teractions (i.e., both anthropoge nic and natural sources) that may allow for understanding into how these inter actions are influencing survival rates, as well as how non-lethal injuri es may be affecting their ability to function (both biologically and ecologically) th roughout their lives. In genera l, this project provides basic biological and ecological information to agencies wo rking to develop conservation and management plans, particularly within nearshore systems. Numerous gaps remain within sea turtle life histor ies that are prohibiting the de velopment of sound long-term management plans. This project attempts to bridge such gaps. Background Population Ecology Fluctuations within wildlife populations are a result of a multit ude of abiotic and biotic factors that both positively and ne gatively affect long-term species viability (Congdon 1989). Parameters such as growt h, reproduction, and survivorship play fundamental roles in shaping species’ populations (Werner and Caswell 1977). For example, survival rates can substantially fl uctuate between age and sex classes within a species (Chaloupka and Limpus 2001). Higher rates of mortal ity are frequently observed within younger cohorts than in the older generations of the sa me wildlife species (Jorgenson et al. 1997). Due to the multip le factors impacting populations, wildlife ecologists must strive to understand as mu ch about species of concern and their ecological systems as possibl e (Jorgenson et al. 1997). Spatial and temporal factors often lim it the amount of information obtainable by ecologists (Akcakaya et al. 1995). This is most critical when the information is needed to determine long-term survival of a species and the development of recovery plans for

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3 threatened or endangered status. In the de velopment of long-term population models it is insufficient to only consider such factors as birth and deaths when immigration and emigration can markedly affect the populati on size, which inherently molds the genetic and evolutionary change within the syst em (Werner and Caswell 1977). Predation and competition are examples of factors that ca nnot be ignored to simplify the process of understanding complex relations hips shaping species popula tions. Wildlife populations can be strongly influenced by a multitude of demographic parameters (e.g., survivorship, growth, and reproduction) that can directly sh ape the viability of a species and therefore determine the species’ long-term survival (Beddington and May 1977). Maturation within some long-lived species may take more than a decade [e.g., the gray whale Eschrichtius robustus may delay maturation up to 11 years of age (Beddington and May 1977)]. Serious problems arise when entire reproducti ve cohorts, especially the individuals that have the highest reproductive success (i.e., usually the older or larger individuals) are removed from the population (Doak et al. 1994 ). This makes species protection (e.g., classifying a population as threat ened or endangered), necessary to prevent extinctions. Vital Rates in Long-Lived Species Further complications arise when atte mpting to understand the complexities controlling long-lived sp ecies populations. As previously mentioned, it is not uncommon for survival rates to be higher among older c ohorts within a populat ion. Such life history traits can have severe impacts within long-li ved species that charac teristically exhibit slow growth and delayed maturation (D ennis et al. 1991). The California condor ( Gymnosyps californianus ) is a prime example of such a species that underwent a severe population decline. The traits of longevity and delayed maturation coupled with low reproductive rates exposed the species to a seve re risk of extinction (Dennis et al. 1991).

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4 The example of G. californianus further demonstrates long-liv ed species’ vulnerability to both natural and human-induced mortality. A cr ucial component in long-lived species conservation is the protection of the olde r cohorts (generally the key producers) (Jorgenson et al. 1997). Wildlife populations are natu rally regulated via various non-anthropogenic methods (e.g., weather, temperature, competition), but th e resulting survivorship rates are in turn negatively affected by anthropogenic fact ors (e.g., encroachment, fishing, and environmental pollutants). For the most part, it is unclear to wh at level humans are impacting wildlife populations because of the difficulty associated with assessing population abundance and survivor ship within some species . Marine organisms living part or their entire lives within ocean systems are among those species whose life histories in large part, remain a mystery. Th is makes it difficult to accurately assess the toll that humans are inflicting on oceanic sy stems. The lack of understanding within marine systems demonstrates the need for more research and protection of such systems. Threats to Sea Turtles Natural and anthropogenic factors within marine and terrestrial environments regulate the long-term survival of sea turtle sp ecies. Sea turtle surv ival probabilities are significantly influenced by human induced-mor tality, such as fisheries interactions involving trawling, longlines, gill/entangl ement, hook and line (Hilburn et al. 1995; Oravetz 1999), marine pollution (McCauley a nd Bjorndal 1999; Bugoni et al. 2001), and may be significantly influenced by natural sources such as disease [e.g., fibropapillomatosis, FP (Smith and Coates 1938) and predation such as birds, crabs, and sharks (Stancyk 1981; Marquez 1990)].

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5 Each factor may impose a different level of threat to sea turtle survival, but assessing this can be difficult in a group of animals largely inaccessible for most of their lives. However, there are opportunities for rese archers to gain insight into factors that may be affecting sea turtle survival probabilities (e.g., in ferring threats from injury identification). This method has been app lied in studies examining predator-prey interactions across several taxa (e.g., re ptiles, zooplankton, and marine mammals) by inferring interactions and relative predation ra tes from new and healed inflicted injuries (Schoener 1979; Murtaugh 1981; Heithaus 2001 a; Heithaus et al. 2002; Shimada and Hooks III 2004). Although inferences that ca n be made from such methodologies are limited, they can prove to be useful in pr oviding information when other methods are unavailable. Study Objectives A primary objective of this project was to gain insight into many types of sea turtle species interactions (i.e., both anthropogenic and non-anthro pogenic sources) that may allow for understanding of how th ese interactions are influenci ng survival rates, as well as how non-lethal injuries may be affecting th eir ability to function (both biologically and ecologically) throughout their lives (e.g., affecting vital rates such as reproductive success). Physical cues (injuries) left from past interactions among turtles and the abiotic and biotic factors within th eir environment were quantified, but before doing so it was first necessary to develop a st andardized Sea Turtle Injury Identification System (STIIS) that would aid in reducing observer error wh en categorizing injury types, causes and locations. The use of this systematic injury identification system is not limited to this project, but can be applied globally by researchers and vol unteers across research and stranding projects assessing bot h live and dead turtles.

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6 As previously discussed, several anthr opogenic and natural f actors regulate sea turtle populations. However, the focus of this project is limited to the types and causes of injuries present on the sea turtles utilizing the neritic zone of the southeastern United States and entrained at the SLNPP. These in clude the following injury sources 1) shark, 2) social interactions among turtles, 3) ba rnacles, 4) fishing (hook, entanglement), 5) oil/tar, 6) boat prope ller strikes, and 7) SL NPP intake pipes. Two primary objectives were identified: OBJECTIVE 1. Develop a systematic Sea Turtle Injury Identification System (STIIS), which researchers could use to dete rmine types and causes of injuries and consistently record injury location. OBJECTIVE 2. Apply the STIIS created in Objec tive 1 to new and hi storical sea turtle capture data at the SLNPP in order to quantify types, causes, and locations of injuries found on th e sea turtles entrained at SLNPP. A. Compare types and causes of injuries among species, size classes and gender. B. Examine the frequency of intake pi pe related scrape s on the turtles entrained at SLNPP. Provide the fi ndings to Florida Power & Light (FP&L) and Quantum Resources.

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7 CHAPTER 2 SEA TURTLE INJURY ID ENTIFICATION SYSTEM Introduction Attempting to identify sources of inju ry in wildlife populations is not a new endeavor. Injury identifica tion has been used across se veral taxa (e.g., reptiles, zooplankton, and marine mammals) to gain in sight into threats that may be impacting imperiled wildlife populations (Schoe ner 1979; Murtaugh 1981; Heithaus 2001a; Heithaus et al. 2002; Shimada and Hooks III 2004). However, one question that has rarely been researched is the effects of nonlethal injuries on an organism’s ability to function and reproduce (Nakaoka 2000) throughout its’ lifetime. This is an especially important concern when individu als in early life stages sust ain permanent injuries that may reduce their reproductive success. With the vast number of sea turtle res earch programs being implemented globally, data sharing can sometimes be a trivia l objective. Methodological and observer differences can thwart the regi onal data sharing process. In this study, a standard injury identification system that could be applied across research projects was identified as a crucial missing component in the field of sea tu rtle injury assessment. Thus, the creation of such a systematic Sea Turtle Injury Identification System (STIIS) was a primary objective in this project. Obtaining standardized data is not the only obstacle when attempting to optimally utilize injury data. An additional source of concern is the task of formatting the data in a way in which it can be statistically analyze d. For example, many researchers are vigilant

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8 and meticulous data collectors, however, it is not uncommon for th e injury data to become embedded and subsequently lost in the “comments column” of an extensive spreadsheet (e.g., a database spanning severa l years or decades). The comments column often contains such information as recapture data, animal behavior observations such as aggression or lethargy, and injury or abnor mality data such as missing flippers or embedded fishing hooks. Unfortunately, many of the details explaining such data are often lost in the transferring of data from field datasheet to electronic spreadsheet, further underscoring the need for a standardized met hod of entering consistent and quantifiable data. Methods Study Area The St. Lucie Nuclear Power Plant (SLNPP) is located on Hutchinson Island (a 36 km long barrier island) in St. Lucie Count y on the east coast of Florida, USA (lat 27 20’N, long 80 13’E). The island is bordered by the Atlantic Ocean on the east, the Indian River Lagoon on the west, St. Lucie Inlet on the south, and the Ft. Pierce Inlet on the north (Figures 2-1 and 2-2). The adjacen t beach is composed of sand and shell hash. The littoral benthic community c onsists of a sandy-shell hash substrate that supports large worm-rock reefs consisting of sabellarid worms ( Phragmatopoma caudata ). The wormrock reefs support high levels of fast-growi ng macroscopic algae (e.g., red algal species such as Bryothamnion, Botryocladia, Solieria and Gracilaria ) (Ecological Associates 2000). The continental shelf margin is approxi mately 30 km offshore from the power plant. The Florida Gulf Stream flows parallel to the shelf margin, and contributes water to

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9 the nearshore system during the summer seas on. The annual coastal water temperatures range from approximately 14 to 31 C (Ecological Associates 2000). Study Site The SLNPP, which opened in 1976, is an electric power ge nerating facility operated by Florida Power and Light (FP&L) . Water drawn from the Atlantic Ocean maintains the plant’s two nuclear fueled units (i.e., condensers and cooling systems) in a circulating seawater cooling syst em (Ecological Associates 2000) Intake system The intake system for the two nuclear units is composed of 1) three ocean intake structures, their associated vertical openings , velocity caps and pipelines, 2) a common canal system, 3) individual unit intake a nd discharge structures, 4) and a common discharge canal leading to a shared disc harge pipeline, which branches to a 3.65 m pipeline conveying water approximately 365 m offshore or a multiport diffuser approximately 4.9 m in diameter conveyi ng water approximately 365-730 m offshore (Ecological Associates 2000). Ocean intake structures The three ocean intake structures are lo cated approximately 365 m offshore. Each offshore structure is composed of a velocity cap and vertical shaft that serve to reduce the vertical entrainment of marine organisms (flora and fauna) and debris, however, no screen or grates are in place that would deny access to the intake pi pes. The velocity cap for each intake pipe is located approximately 2.1 m below the water surface at mean low water. One intake pipe is 4.9 m in diameter with a 1.5 m thick velocity cap measuring 6.5 m2 and a vertical shaft opening of 1.9 m. The second and third intake pipes are 3.65 m in diameter, with 1.5 m thick velocity cap measuring 4.8 m2 and a vertical shaft opening of

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10 2.0 m. Water entering under the ve locity caps shifts to a vertical flow pattern with water flow velocities of 40.2cm/sec for the 3.65 m pipe, and 206 cm/sec for the 4.9 m pipe. Flow velocity inside each of the pipes ra nge from 127-206 cm/sec and the estimated time for an object to travel the offshore pipeline to intake canal distance of 365 m ranges from 3-5 minutes. This varies depending on the inta ke pipe and degree of fouling inside the pipes. Water passes into each intake pipe’s ve rtical shaft and enters a horizontal intake pipe, which is buried under the plant’s adjacent beach and dune system (Ecological Associates 2000). Intake canal and discharge system The water from each horizontal intake pipe empties into a shared canal system (approximately 450 m behind the primary dune line), which carries the water 1,525 m before it reaches one of the two nuclear unit in take structures. The can al is 91 m wide and approximately 7.6 m maximum depth with a flow rate of 27-32 cm/sec depending on tidal stage. The incoming water passes th rough the plant’s cooling system, and the resulting heated water is then released back into the ocean via two separate pipes, located 365 m and 730 m offshore (Eco logical Associates 2000). Barrier net implementation and modification program A series of barrier nets have been er ected, modified, and replaced at various locations along the canal system since 1978 in efforts to accomplish two primary purposes: 1) to restrict turtle s (in addition to other floati ng debris) from moving down the canal system towards the plant’s intake wells a nd 2) to establish an efficient netting turtle capture program to minimize the residency time of the turtles in the canal. In addition to turtle entrapment within the canal, other marine organisms and debris are entrained

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11 within the intake pipes and discharged into the canal, such as jellyfish, seaweed and flotsam (Ecological Associates 2000, Quantum Resources 2004). The size of the mesh of each barrier ne t erected since 1978 ha s been dependent on the size frequency of the turtles captured at the plant prior to each net’s construction. In 1978, a large barrier net (20.3 cm2 mesh) was erected at the A1A bridge in an attempt to limit 95% of the sea turtles to the canal se ction east of the A1A bridge. However since 1993, a significant increase in the number of juvenile gr een turtles (<30 cm carapace width) have been entrapped within the canal . A large percentage of the juvenile green turtles were able to pass through the 20.3 cm mesh net and subsequently carried down the canal system to the plant intake wells, wh ere they were later removed (e.g., in 1995, 673 green turtles were captured in the canal, 14.4% (n=97) pa ssed the 20.3 cm net and 7.2% (n=7) were recovered dead from the in take wells. The 20.3 cm net was deemed insufficient after continued increases in tur tle entrapment rates. In 1996, an additional barrier net (12.7 cm2 mesh) was erected east of the 20.3 cm barrier net, while the 20.3 cm barrier net was left in place. The 1996 net re duced residency times for the turtles in the canal, but proved to be unsuccessful when its design was compromised by large amounts of seaweed and jellyfish. In 2002, a new ba rrier net was constr ucted using stronger material and increased structural support. Th is net has been able to withstand high pulses of seaweed and jellyfish, and has significan tly reduced the likelihood of turtle mortality in the canal (Ecological Associat es 2000, Quantum Resources 2004, 2005). Procedures Sea turtle capture program Since 1976, an estimated 10,500 sea turtles (i ncluding recaptures) of five species ( C. caretta , C. mydas , D. coriacea , E. imbricata , and L. kempii ) have become entrained

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12 in the water entering the plant’s canal syst em. All sea turtle species are listed as threatened or endangered in the U.S. Endange red Species Act of 1973. In order to reduce impacts by canal entrainment (injuries, re sidency time in canal, mortality), FP&L has maintained a sea turtle mon itoring and review program with two biological contracting companies since opening in 1976, Applied Biology, Inc. (1976-1994), and Quantum Resources, Inc. (1994-present) . The sea turt le monitoring program involves a proficient daily observation, netting and removal program. Large-mesh tangle nets (30-37 m length and 2.7-3.7 m deep) with large floats attached to the top line (bottom line is not weighted) are set in the morning when the staff arrive s, and are monitored throughout the day. Nets are removed before the staff leaves to eliminate the possibility of entanglement and drowning of animals within the canal. Dip nets and SCUBA are employed in addition to set-netting to further reduce the residency time of turtles entrained in the canal (Quantum Resources 2004, Quantum Resources 2005). Captured turtles are individually pr ocessed, which includes: 1) species identification, 2) obtaining several morphol ogical measurements (e.g., carapace lengths and widths, head width, and wei ght), 3) application of extern al and internal tags [i.e., Inconel flipper tags and Passive Integrated Transponder tag (P IT)], 3) full assessment and notation of any injuries, abnormalities, parasites and, 4) photo documentation. Photographs are filed according to capture date and data is recorded on a standardized datasheet in the field and later entered in to a Microsoft Access database. The relative condition of each turtle is assigned (i.e., good, fair, poor or dead) based on a multitude of factors such as weight, activ ity, parasite load, barnacle c overage, injuries and other factors that may affect th e overall condition of the tur tle (Quantum Resources 2005).

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13 Each turtle is assigned a tu rtle identification number (Tur tle ID), which corresponds to the code of the first tag (a combination of letters and numbers) appl ied to the turtle. The presence or absence of a tag on a turtle is the primary indicator used in determining whether or not the turtle has previously b een captured at the SLNPP or elsewhere. A turtle is categorized as a recap ture if previously captured at SLNPP and a new capture if it has not been captured at SLNPP. One inte rnal PIT tag (inserted in the front right flipper) and two external Inconel tags are applied to ne w captures > 30 cm straight-line standard carapace length (SSCL). Turtles < 30 cm SSCL receive only a PIT tag in the front right flipper. After processing, healthy turtles are released b ack into the adjacent coastal waters ~800 m from the intake sites on the day of capture (B resette et al. 1998). Turtles that are sick or injured are treate d, and when necessary are held for observation before being released (Quantum Resources 2005). Turtles requiring further medical evaluation/treatment are sent to an approved rehabilitation fac ility after contact with the Florida Fish and Wildlife Conservation Commission (FFWCC) (Quantum Resources 2005). Description and Discussion Sea Turtle Injury Identi fication System (STIIS) This project utilized both historical and new data colle cted from SLNPP during the period of May 2000 through July 2005. This de cision was based on the knowledge that the core sea turtle research staff (those employed year-round) at the SLNPP has remained stable from May 2000 through July 2005 with the exception of one new hire during 2005. The new hire was considered ‘in-training’ a nd was largely overseen by senior research members. Furthermore, data collected during late summer/fall of 2004 (August to December) was not used because of the disruption of normal plant operation due to the

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14 hurricanes that occurred in Florida duri ng 2004. Data collected May through December 2000 was used as a baseline year from whic h the STIIS was developed. Injury types and causes were determined for all cap tures in the 8-month period. In order to consistently id entify injuries within each categorical region, a film transparency was produced containing the corresponding sea turtle diagram found on the field datasheet. Diagrams (n=4) from each of the 5 years were scanned on an IMAX flatbed scanner (original scale maintained) a nd printed on a standard sheet of white paper (20 cm X 28.75 cm). Each diagram was s ectioned based on biol ogical and ecological criteria. The same principals were applie d when sectioning the flippers into four subsections. Biological and eco logical information used included: 1) bone and joint location, 2) the location of th e claws on the front flippers and the scooping portion of the rear flippers, and 3) the standardized placemen t of both internal tags (PIT) and external tags (Inconel flipper tags). Sectioned diagrams were scan ned using the IMAX flatbed and printed on a clear transparency. This transpar ency sheet was instrumental in recording consistent injury location data from th e standard SLNPP datasheets throughout the project. Turtle captures were evaluated for types, causes, and locations of injuries by close examination of each turtle’s corresponding field datasheet and photographs. Photographs were available in slide and/or digital formats. More than 2,000 slide photographs were examined utilizing a Logan Tru-View light box (Logan Electric, Chicago, Illinois, USA) and a Carson 10X-magnifying lens. Injury causes were identified by characteristic markings/wounds (cues) of each injury type. Injury location was assigned by placing the diagram transparency (described in the prev ious section) over each of the corresponding

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15 datasheet’s dorsal/ventral diagram. Injury information recorded included: 1) the anatomical region (general body region), 2) numerical region which is a single number and series of letters corresponding to subs ections within a general body region (some anatomical regions were not subsectioned and thus only consisted of a single number), 3) the view of the injury (i.e., dorsal, dorsal/ven tral, and ventral), 4) in jury type, 5) injury depth (superficial or deep), 6) injury condition which descri bes the temporal occurrence (recency) of the injury (i.e., fresh, partial, or healed) by the presence/degree of wound closure and fibrin deposition (Table 2-1), and 7) injury cause. If the same injury (identical in injury locati on, type, depth, condition, and cause ) occurred more than once within the same body region, it wa s recorded as a single reco rd. For example, a turtle with five fresh scrapes on the head would be recorded as a single fresh scrape record on the head region. Attention was given to field notations on each datasheet describing the turtle’s condition/injury. Non-descrip tive injuries were classifi ed as unknown. Discrepancies between datasheets and photographs were corr ected, ensuring the robustness of injury identification within this study. Each injury should be recorded using the diagram and fields found in Fig. 2-3. Researchers should first begin by identifying th e anatomical region location of the injury. This should be followed by determining th e numerical region and subregion (when applicable). The injury view should be id entified by the corres ponding dorsal and/or ventral diagrams (dorsal/ventra l) of which the injury is lo cated. Missing portions of the carapace or flippers would be classified as dorsal/ventral. The type of injury should be closely evaluated, as certain t ypes (cues) are indicative of cer tain sources of injury. The

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16 depth of injury should also be strongly evaluated. Superficial wounds are generally defined as those removing only minor amount s of scute/scale/tissue, which does not result in exposure of bone, muscle, internal viscera, or moderate to extreme blood loss. Deep wounds are generally defined as those of which moderate to extreme tissue/blood loss may occur, which may require medical attention. Injury recency should be determined by the criteria outlined in Table 2-1. The cause of the injury should be determined by the injury types (cues) (refer to the text and photographic descriptions in the following sections for further details). If the type of injury is non-descriptive, then it is appropriate to categorize the injury as unknown. Some proj ects may experience injury types and causes that are not represented in Fig. 2-3, in such cases, project personnel should make the appropriate additions to meet their project needs. During the initial application of such an identification sy stem, one could argue that time constraints (i.e., handling and processing) in the field would not allow for such detailed record keeping of each observed inju ry. However, consistent use of such an identification system does have practical application, and may prove to be extremely efficient and valuable now and in the future . For example, by keeping organized records of what are referred to as ‘unknown’ injuries now, researchers may be able to detect trends in injuries, which may aid in identif ying potentially rising and serious threats to sea turtle populations in the near future. Injury Types/Causes Flipper amputation Flipper amputation was defined as a c ontinuous missing portion beginning on one margin of a flipper and follo wing through to the opposite margin, as opposed to a missing section from one margin (crescent-shaped, v-shaped, and u-shaped notches). Flipper

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17 amputations were categorized according to the percentage of flipper missing: 1) less than half (<50%), 2) half (~50%), 3) over half (51-80%), and 4) entire (81-100%) (Fig. 2-4). Barnacle Injuries related to barnacles were determ ined by superficial to deep depressions, generally found on the carapace or plastrons region (Fig. 2-5). Shark-related Shark-inflicted injuries were determined by the criteria outlined in Table 2-2. Only flipper amputations coupled with apparent punctures and/or missing crescent-shaped sections with tooth impressions were classified as shark-rela ted injuries. Once the healing process has commenced, the ability to identi fy shark-related injuries may become less obvious and therefore less indi cative of a shark-turtle in teraction. Fig. 2-6 contains photographs of sea turtles w ith shark-related injuries. Social interactions Indicators of social interactions among tu rtles include 1) circul ar bites on the neck region of females, 2) symmetrical abrasions on the trailing edges of the flippers in males indicative of reproductive activity (Fig. 2-7), 3) symmetrical creases on the plastron of males (Fig. 2-7), and 4) symmetrical s cars under the front flippers on females. Boat propeller In this study, identification of boat-relate d injuries was limited to propeller strikes (Fig. 2-8). Carapace cracks were not identified as boat-related because of the inability to distinguish hull strikes from other high-impact injury sources (Fig. 2-9). Cracks in the carapace are often assumed to be boat-related, however, within the scope of this project causality was not assigned without additional indicators such as lacerations. Propeller strikes were identified by one to several la cerations found on the head, carapace, flipper,

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18 and plastron regions. Boat propeller lacerations differ from other slices or cuts typically by the severity of the wound, in cluding the length, width an d depth. It is not uncommon for such lacerations to be grouped in a pa rallel configuration s howing the rotational movement of the boat propeller that struck the turtle. Fishing interactions Injuries categorized as fishing related in cluded: 1) monofilament entanglement, 2) embedded fishing hooks (generally found in soft tissue areas such as the neck, flipper, mouth or eye region), and 3) strangulation wounds (superficia l to deep scars) around the base of the flipper or neck region (Fig. 210). Turtles found with attached fishing line and/or hooks were closely evaluated. If the line or hook was found to be superficial it was removed and the turtle was rele ased, however, if the line wa s deeply embedded the turtle was sent to a rehabilitation facility. Intake pipe Intake pipe related injuries were iden tified by fresh scrapes on the body (lack of observable fibrin deposition) resulting from entrainment through one of the three intake pipes at the SLNPP (Fig. 2-11). Oil/tar Oil/tar related injuries were identified by the presence of oil or tar on the body (Fig. 2-12). Unknown Unknown injuries were classified as such when no distinguishable cues (injury was non-descriptive) were present that would indicate a known injury source (Fig. 2-13).

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19 Figure 2-1. St. Lucie Nuclear Power Plant lo cated on Hutchinson Island, Florida, USA. FPL

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20 Figure 2-2. Aerial view of th e St. Lucie Nuclear Power Plan t and nearshore reef system. The barge was present in 1991 during the reconstruction of the intake pipe’s velocity caps. Atlantic Ocean St. Lucie Nuclear Power Plant Indian River Lagoon FPL

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21 Anatomical Numerical View Injury Type Depth Injury Condition Cause Head 1 Dorsal Abrasion Superficial Fresh Barnacle Carapace 2abcd Dorsal/Ventral Amputation Deep Partial Shark Front Left Flipper 3abcd Dorsal/Ventral Bite Healed Social Front Right Flipper 4abcd Dorsal/Ventral Broken Boat Propeller Strike Rear Left Flipper 5abcd Dorsal/Ventral Crack Fishing Rear Right Flipper 6abcd Dorsal/Ventral Crease Intake Pipe Plastron 7abcd Ventral Cut Tar Cloaca/Tail 8 Dorsal/Ventral Depression (pitted/indented) Unknown Left Eye 9 Dorsal Discoloration Right Eye 10 Dorsal Hole Mouth (Jaws/Esophagus) 11 Dorsal/Ventral Missing Neck 12 Dorsal/Ventral Missing (crescent-shaped) Missing (marginal) Missing (scalloped) Missing (u-shaped marginal) Missing (v-shaped) Puncture Raised Rake Marks Scrape Slice Other Figure 2-3. Sea Turtle Injury Identification Sy stem (STIIS) developed by A.D.Norem.

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22 Figure 2-4. Flipper Amputations. A) C. mydas missing less than half of rear right flipper (numerical region 6ab). B) C. caretta missing half of front left flipper (numerical region 3ab). C) C. mydas missing entire rear left flipper (numerical region 5abcd). B C A FPL FPL FPL

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23 Figure 2-5. Two deep barnacle depressions on the 3rd vertebral on the carapace of a juvenile C. mydas (numerical region 2abcd). FPL

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24 Figure 2-6. Shark-related injuries. A) Rake marks from shark on posterior end of C. caretta carapace (numerical region 2ab). B) Crescent-shaped portion of posterior end of carapace removed with slashing wounds from shark on dorsal side of tail (numerical regions 2ab an d 8). C) Tooth impressions and slashing wounds from shark on posterior end of plastron and on rear flippers; same C. caretta as in photograph A (numerical regions 7ab, 5cd and 6cd). A B C FPL FPL FPL

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25 Figure 2-7. Injuries resulting from social interactions among turtles. A) Male C. mydas with symmetrical creases on plastron i ndicative of mating activity (numerical region 7abcd). B) Symmetrical abrasion on rear left flipper on adult male C. mydas (numerical region 5ab). A B FPL April Norem

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26 Figure 2-8. Boat propeller injuries. A) S lice wounds in paralle l configuration on C. caretta carapace (numerical region 2b). B) Dorsal photograph of boat propeller slice through head on juvenile C. mydas . A B FPL FPL

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27 Figure 2-9. Cracked carapace on C. caretta (numerical region 2cd).The cause of injury was classified as unknown. FPL

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28 Figure 2-10. Fishing-related in juries. A) Monofilament stra ngulation of the front right flipper on C. mydas (hook and sinker attached, numerical region 4cd). B) Fishing hook with monofilament attached embedded into front right flipper on C. caretta (numerical region 4c). C) Fishi ng hook embedded into the right eye of juvenile C. mydas (hook and sinker attache d, numerical region 10). D) Strangulation wound on front right flipper of C. caretta (numerical region 4cd). A B C D FPL FPL FPL FPL

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29 Figure 2-11. Fresh scrape injuries. A) Fresh scrapes on carapace of C. caretta (region 2abcd). B) Dorsal view of head on C. caretta exhibiting several fresh scrapes, note deep fresh scrape above right ey e (numerical regions 1 and 10). C) Close-up view of fresh scrape on cara pace. D) Side view of juvenile C. mydas head showing fresh scrapes between right eye region and mouth, and below right nare (numerical regions 1 and 11). A B C D April Norem April Norem April Norem FPL

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30 Figure 2-12. Oil on the ventral side of C. caretta (numerical regions 3abcd, 4abcd, 5abcd, 6abcd, 7abcd, and 8). Figure 2-13. Symmetrical non-descrip tive injuries on the plastron of C. caretta (numerical subregion 7ab). The cause of injury was unknown. FPL FPL

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31 Table 2-1. Categories of injury recency (fresh, partially healed, and healed). Fresh Exhibiting no signs of closure or fibrin deposition. Partially healed Exhibiting some signs of scute/scale growth around the wound, in addition to fibrin deposition within the wound. Healed Exhibiting signs of complete scute/scale growth, resulting in full closure of the wound. Table 2-2. Shark-related injury criteria. Each criterion ma y be mutually exclusive. Criterion number (1) Obvious shark tooth impressions/ra kings located on any region of the body. (2) Crescent-shaped section removed fr om carapace or flipper that could only have been caused by a shark. (3) Flipper amputations coupled w ith tooth impressions, punctures, and/or slashing wounds indicative of sharks.

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32 CHAPTER 3 ANTHROPOGENIC AND NON-ANTHRO POGENIC INJURY ANALYSES Background Non-anthropogenic Threats to Sea Turtles Sharks Several examples exist within the literature of sharks being listed as likely sea turtle predators, but the extent of predation pressu re placed on turtles by sharks is relatively unknown. Previous literature reviews have noted six shark species to be likely predators of sea turtles: bull ( Carcharhinus leucas ), hammerhead ( Sphryna sp.), lemon ( Negaprion brevirostris ), oceanic white tip ( Carcharhinus longimanus ), tiger ( Galeocerdo cuvier ), and white ( Carchardodon carcharias ) (Stancyk 1982). The tiger shark, however, is the only species cited as preying extensively on large cheloniid (hard-shelled) sea turtles (Stancyk 1982; Witzell 1987; Heithaus 2001b; Simpfendorfer et al. 2001). Significant temporal and spatial habitat overlap exists between sea turtles and sharks (Witzell 1983, 1987; Marquez 1990) a nd both animals exhibit a series of ontogenetic shifts (i.e., geogr aphical and diet) throughout th eir lifetimes (Meylan and Meylan 1999; Simpfendorfer et al. 2001). Sea tu rtle hatchlings leav e their natal beaches for an oceanic (open ocean environment exceeding bottom depths of 200 m) existence for a period of years, whereas juvenile, subadult (transitional), and adult cheloniid sea turtles are sympatric with several shark species in th eir wide utilization of neritic zones (inshore coastal waters not exceeding bottom depths of 200 m) such as lagoons, salt marshes, bays, creeks and river mouths (Ernst et al. 1994). Furthermor e, occurrences of sea turtle-

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33 shark interactions may vary depending upon factors such as diet and geographical distribution among species, sex and size class of both organisms. This variation is clear if one reviews global examples of shark stom achs containing parts of and/or whole sea turtles. Fergusson et al. (2000) de scribed a 60 cm loggerhead turtle ( Caretta caretta ) removed from the stomach of a female white shark 550 cm total length TL caught in the Mediterranean Sea. A 295.2 cm TL tiger sh ark captured in the Eastern Caribbean was reported to contain a partially digested ~30 cm hawksbill turtle ( Eretmochelys imbricata )(Young 1992). Balazs (1979) reported va rious turtle parts (e.g., mandible, plastron, and carapace) belonging to a 55-60 cm loggerhead turtle within the stomach of a 400 cm tiger shark caught off of Kure Ato ll in the Northwestern Hawaiian Islands. Moreover, behavioral differences between male and female turtles may lead to significant differences in the rates of sea turtle-shark interactions, and subse quent injury rates. Heithaus et al. (2002) concl uded that loggerhead turtle s (n = 115, mean = 89.7 12.0 SD) exhibit higher rates of shar k-related injuries than green turtles (n=133, mean = 90.7 13.2 SD).This same study speculated that male loggerhead turtles may incur higher injury rates of shark-related injuries in comparison to female loggerheads, as well as male and female green turtles, because they engage in behaviors that could be considered higherrisk (Heithaus et al. 2002). Social interactions Very little is known about injuries incurred from soci al interactions among sea turtles. It has largely been presumed that tu rtles are predominantly solitary animals, with the exception of social grouping during c ourtship and mating (Carr 1995). However, Dodd (1988) reported aggregations of both juvenile and adult loggerheads. Mating occurrences have been observed with a male typically mounting a female. This may

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34 involve some preand inter-bit ing behavior on the flipper an d/or neck region (Miller et al. 2003) and the males clasping to the female carapace via enlarged and strongly curved claws (sexually dimorphic trait found only in mature individuals, Kamezaki 2003) during mating (Ernst et al. 1994; Gulko and Eckert 2003; Miller et al. 2003). In addition to injuries between male and fema le mating pairs, minor to serious injuries may arise from competition among other turtles for space or mating opportunities. For example, loggerhead turtles have been observed e xhibiting aggressive behavior towards conspecifics by attempting to or actively bi ting them when they were too close (Limpus and Limpus 2003). This study quantified wounds indicative of social interactions among turtles. Examination of wounds resulting from mati ng interactions may allow researchers to identify wound types and locations indicativ e of reproductive activity and/or social interactions with other turtle s, as well as estimating the timing of such events based on the recency of the wound. Barnacles Barnacles have been recorded among the epibionts found on sea tu rtles, specifically within C. caretta (Frick et al. 1998). Barnacles may nega tively affect a turtle’s health by inducing tissue damage, which may allow pa thogens to enter the body (George 1997). Anthropogenic Threats to Sea Turtles Commercial and private boating The direct and indirect effects of boa ting activity on sea tu rtle populations are largely unknown. Air breathing marine orga nisms such as sea turtles and marine mammals (e.g., manatee Trichechus sp .), are at high risk of bei ng struck by boats because they must surface to obtain the oxygen required to survive. In addition, activities such as

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35 basking, mating, and resting at the surface make the animals susceptible to boat strikes. Moreover, sick or injured turtles may spe nd significant amounts of time at the surface and may be incapable of diving properly to avoid approaching boats. The ability of turtles to detect approaching water vessels via audi tory and/or visual cu es in the wild is unknown due to the difficulty of observing and measuring such interactions. However, some information is available on the auditory capabilities of loggerhead and green turtles. For example, Ridgway et al. (1969) concluded that the auditory func tion in green turtles is optimal for detecting lower frequencie s between 60Hz and 1000 Hz (peaking between 300Hz and 400 Hz). Moein et al. (1999) studied the auditory capabilities in 35 juvenile loggerhead turtles and found that their heari ng was also specialized for low frequency sounds with optimal detec tion between 250 Hz and 750Hz (peaking around 250Hz). An additional study by Lenhardt et al. (1983) found that bone-conducted (bc) sound was a reception mechanism for marine turtles with the carapace and skull functioning as the receiving surfaces. Despite the specialized capab ility of marine turtles to hear low frequency sounds, the time available between a turtle detecting an oncoming boat and di ving to escape being struck by the hull or propeller may be insuffi cient even for turtles in healthy condition. This problem may be exacerbated if the turtle is in shallow water and unable to dive deep enough to avoid collision with an oncoming boat motor. Boat propeller strikes may result in lacerations, fractures, paralysis, buoya ncy problems, breathing difficulties, and mortality (Walsh 1999). The level of boat traffic within an area may give some indication of the threat that boating may impose on sea turtles. For exampl e, the Sea Turtle Stranding and Salvage

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36 Network (STSSN) have reported many sea turtle boat propeller injuries off coastal states that have high levels of boat traffic (Ecologi cal Associates 2000). However, it is very difficult to determine how many of these dead st randed turtles died as a result of being hit by a boat, or were struck post-mortem (after they were already dead). The 2004 Florida Boating Statistics indicate that boat regi stration increased by 0.5% (n=4,682) from 20032004, reaching 982,907 vessels registered. This pr oject, however, recognizes that time and place of capture does not necessarily equal time and place of injury. This project had the rare opportunity to quantify the frequency of boat propeller strikes in live sea turtles (and thus quantifyi ng boat propeller strike survivors) utilizing the nearshore system of SLNPP. Compari ng the frequencies of boat propeller injuries among species and size class may provide ne w information for researchers to use to estimate how many turtles are sustaining such injuries. This may indicate the level of threat that boating activity poses to sea turtles, as well as assessing the health impacts (e.g., paralysis and/or buoyancy problems) of such injuries. Marine debris Marine debris can be described as items discarded by hu mans (purposely or inadvertently) into the marine environment. This includes trash from both land-based and water-based human activities. The Ocean Conservancy’s (TOC) 2004 International Coastal Cleanup report stated that over 7 milli on pounds of debris were removed from the marine environment. An example of the most deleterious types of debris in marine system is derelict fishing gear (nets, fishing line and hooks) from commercial and recreational-based fishing activities. It is not uncommon for marine organisms to be become entangled and drown in fishing line (Milton et al. 2003), nor is it uncommon for marine organisms to either directly or indi rectly consume marine debris. It has been

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37 estimated that one third to one half of all sea turtles inge st plastic products (Gulko and Eckert 2003). Among the items that have been found in sea turtle digestive tracts are plastic bags, beads, pellets, rope, latex balloons, styrofoam, fish hooks, charcoal, glass, paper and cardboard (Milton et al. 2003). L eatherback sea turtles are known to mistake plastic bags for jellyfish, which are one of th eir primary food sources (Milton et al. 2003). A study conducted by McCauley and Bjorndal (1 999) found that consumption of marine debris by posthatchling loggerhead turtles imposes an indirect and direct lethal effect that may lead to decreased growth rates, an increa se in the time the turtles remain in smaller size classes increasing their risks of pred ation, reduction in energy reserves and reproductive output, and decrea ses in survivorship. In this study, only impacts of marine debris that could be observed externally were quantified. This included hook and line enta nglement and presence of tar/oil on the turtles. It is unknown how many of the turtles captured at the SLNPP contain marine debris within their digestive tracts. Oil and tar pollution In the marine environment, sea turtles are exposed to continuous levels of oil throughout their lives in the form of tarbal ls and slicks. Such long-term exposure may degrade the turtle’s ability to deal with other natural and anthr opogenic stresses (Milton et al. 2003) by damaging organs and in creasing drag (Gulko and Eckert 2003). Posthatchling and oceanic staged turtles may be more vulnerable to oil slicks because they spend more time at the waters surface th an juvenile, subadult and adult sea turtles (Milton et al. 2003). In a study examining pos thatchling loggerhead tu rtles, Witherington (1994) found that 63% of the turtle sample d (n=103) were found with tar upon stomach or mouth examination.

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38 Oil and tar exposure in this project was recorded by the presence of the substances on the exterior of the turtles. Turtles lack ing external cues of oil and tar were not accounted for in this project. Sea Turtle Life History Traits Flipper function The front and rear flippers serve several key functions in a sea turtle’s life. Beginning with the initial steps of hatching a nd exiting the egg chamber, turtles must use their flippers to dig out in a facilitative manner. In order to reduce mortality resulting from predation and/or heat consumption, ha tchlings must crawl hastily from the egg chamber to the surf. Malformed flippers can impede this process which may lead to mortality. Turtles use their front flippers to propel themselves forward in the water and their rear flippers in a rudder-l ike fashion to steer. It is probable that the turtles use their flippers in several modes th at are still unknown. However, it is known that the front and rear flippers are important for both males and females during repr oductive periods. The second claw of the front and rear flippers ar e secondary sex characteristics within male sea turtles (Gulko and Eckert 2003; Kamezaki 2003). During copulation, male turtles will use these claws to grasp onto the female (Ernst et al. 1994). It is unknown if males lacking these claws and/or flippers have lowe r reproductive fitness th an those males with claws. More research is needed is this area. However, the nesting process of adult fema le turtles has been studied extensively. The females use their front and rear flippers to construct a body pit a nd their rear flippers to dig an egg chamber (Miller et al. 2003). Generally, turtles missi ng a rear flipper are unable to dig a proper egg chamber that can hol d the clutch of eggs (Miller et al. 2003). Other flipper functions among sea turtles ma y include defense, cleaning and foraging

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39 tools. Loggerhead turtles have been observ ed to mine for their food by sweeping their front flippers across soft-bottom habitats to expose buried prey items (Preen 1996). Davenport and Clough (1985) suggested that young loggerhead hatchlings may use prominent scales (pseudoclaws) on their front flipper to gain access to food items such as vegetation and holeotherms (e.g., medusae). Howe ver, the presence of these scales may vary geographically as well as with age (Davenport and Clough 1985). This same study noted that the young turtles used their rear fl ippers in a brake-like fashion to stabilize themselves when utilizing their front flippe rs as foraging tools (Davenport and Clough 1985). Body region susceptibility Sea turtles spend the majority of their lives in the sea. At various life stages, turtles occupy different regions within the wate r column (e.g., upper, middle, and lower stratums). Utilizing such a myri ad of zones increases the type and causes of injuries that the turtle may incur. As previously menti oned, one objective of this study is to gain insight into whether or not certain regions of the body are more susc eptible to injuries. The significance of an injury can vary depending on its location on the body. Some regions of the body serve critical key functions . One way of obtaining this information is to record the location of wher e the injury was found (i.e., dor sal or ventral). This also suggesting the direction the injury source came from. Howe ver, when a region of the body is missing (e.g., a flipper or portion of th e carapace) the direc tion from which the injury was sustained is unknown. Therefor e such injuries were classified as dorsal/ventral. If certain regi ons of the body are more prone to injuries than others, this information may be of use to researchers de veloping research techniques (e.g., telemetry

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40 and flipper tags) and defini ng locations of the body where the life of the equipment would be optimized. Methods Statistical Analysis Injury analysis: May through December 2000 A Loughin Scherer (LS) permutation chi-s quare test was used in the statistical program S-Plus version 7 to test for significan t differences (associations) in the causes of injury found among species, size class, a nd sex class (Loughin and Scherer 1998). Injury causes were not counted more than on e time per Turtle Id (thus avoiding pseuodoreplication of injury causes when ev aluating recaptures during the study period). Boat propeller and flipper amputation analysis: May 2000 through July 2004 A nave Chi-square test wa s used in the statistical pr ogram SAS version 9.1 to test for significant differences (associations) in boat propeller and flippe r amputations within species, life stage, and sex from May 2000-Ju ly 2004. Amputations or boat propeller strikes were not counted more than one time per Turtle Id (thus avoiding pseuodoreplication of injury causes when ev aluating recaptures during the study period). Captures involving D. coriacea , E. imbricata , and L. kempii were removed from flipper amputation and boat propeller analyses due to too few captures compared with C. caretta and C. mydas . Since sea turtles may be more susceptible to boat propeller strikes and incurring flipper amputations during different life st ages, turtles capture d between May 2000 and July 2004 were divided into three life stages (i .e., juvenile, transitional, and adult). It is assumed in this project that juvenile turt les would be individuals within smaller size classes in the neritic zone. A dult turtles are assumed to be those turtles that may be

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41 moving between neritic foraging habitats and neriti c internesting habita ts through oceanic corridors. Turtles below 71 cm SSCL were classifi ed as juveniles, >85 cm SSCL were classified as adults, and tu rtles 71-84 cm SSCL were classi fied as transitional turtles (Hirth 1980). The distinction be tween juvenile and transition al turtle’s was based on the high numbers of turtles found within the 60-69 cm SSCL. This may be an indication of life history differences between the 60 and 70 cm SSCL size classes. Although assessing a turtle’s maturity by size is an imprecise method according to Limpus and Limpus (2003), grouping different size/age cl asses together may be a valuable method when testing for certain types and sources of injury threats within life stages. This is based on the id ea that turtles found in the ne ritic and oceanic habitats may be subjected to different thre at levels. In the Atlantic O cean, juvenile loggerheads leave the oceanic zone around 46-64 cm curved ca rapace length (CCL) and recruit into the neritic zones (Bjorndal et al. 2000). Green tu rtles recruit into th e neritic zone around 2035 cm CCL (Bjorndal 1997). Fortunately, some progress has been made with loggerhead life history patterns, however, several gaps remain within green turtles (Bolten 2003). Adult loggerhead and green turtles may undergo seasonal moveme nts through oceanic migration corridors between neritic foraging habitats and neri tic internesting habitats (Bolten 2003). Water depth differences in the neritic (< 200 m) and oceanic zones (>200 m) combined with a turtles location in the water column (i.e., pela gic, epipelagic, or benthic) may alter the threat sources within each lif e stage. For example, Murphy et al. (2003) noted that large immatures and adults are observed on the outer zones of continental shelves. In theory,

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42 these turtles would be at less risk of being struck by recreational boats than smaller size classes found in the shallower inner zones of the continenta l shelf. Witherington (2003) speculated that older neritic stage juveniles may migrate hundreds of kilometers among foraging areas. Results May through December 2000 Captures A total of 511 turtles (including recap tures) were captured between May and December, 2000. A total of 448 individual turtles ( C. caretta , C. mydas , and E. imbricata ) comprised the 511 captures (Fig. 3-1). A total of 10.7% (n=48) of the 448 individual turtles captured were classified as recaptures (i.e., prev iously captured during the time period of May through December 2000) and 24.6% (n=126) of the 511 total captures were classified as recaptures during or prior to the study period of May through December 2000 (Fig. 3-2). The turtles range d in size from 26.2-106.8 cm SSCL (Table 31 and Fig. 3-3). A total of 96.1% (n=491) had a body condition index of good, 2.9% (n=15) were in fair condition, 0.6% (n=3) were dead, and 0.4% (n=2) were in poor condition (Fig. 3-4). The three dead turtles consisted of 2 juvenile C. mydas and 1 juvenile C. caretta . The death of one C. mydas was attributed to plant operations. The turtle was found with its head and front left f lipper entangled in the first barrier net. The remaining dead C. mydas was found moderately decomposed floating in the canal with its eyes and front left flipper missing. The juvenile C. caretta was emaciated (sunken plastron) with no apparent injuries with th e exception of a small missing section from its lower jaw. A total of 14.1% (n=72) of the 511 captures were classified as not injured. Of the 72 turtles classified as not injured, 75% (n= 54) were classified as new recruits (35 C.

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43 caretta , 18 C. mydas and 1 E. imbricata ), whereas 25% (n=18) were classified as recaptures (during or prior to the year 2000) (9 C. caretta and 9 C. mydas ). A total of 85.9% (n=439) of the 511 captures we re classified as injured. Of the 439 turtles classified as injured, 75.4% (n=331) were cl assified as new recruits (191 C. caretta , 131 C. mydas and 1 E. imbricata ), whereas 24.6% (n=108) were classifi ed as recaptures (during or prior to the year 2000) (24 C. caretta and 84 C. mydas ). Injuries were categorized into anthropogenic (i.e., tar, boat propeller strike , and fishing), non-anthropogenic (i.e., shark, social, and barnacle), and unknown. The total nu mber of records for each cause of injury can be found in Fig. 3-5 and Table 3-2. Anthropogenic injuries accounted for injuries on 11 turtles (not including intake-p ipe related injuries, which are discussed in chapter 4). A total of 288 turtles were found to have non-desc riptive injuries that were classified as unknown. A total of 858 injury r ecords were found on the 511 captures (Table 3-3). Of these, 53.5% (n=459) were dorsal injuries, 19.7% (n=169) were dorsal/ventral, and 26.8% (n=230) were ve ntral injuries. The type of injury sustained by a turt le was not independent of species ( p =0). However, it is unclear if the type of injury sustained is exclusively species dependent, or if it is a size effect and/or species effect. A limitation in tes ting for species effect is the considerable differences in the mean size cl asses captured for each of the species (i.e., loggerhead turtles (n=243, mean = 79.0 13.1 SD) and green turtles (n=203, mean = 46.4 19.7 SD). Size class analyses indicate that type of injury sustained was not independent of size class. Size class dependency analyses within C. mydas included none, intake pipe, unknown and other (i.e., fishing, so cial, boat, and barnacle) ( 2=55.94, p =0.002). Size

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44 class dependency analyses within C. caretta included none, intake pipe, shark, unknown, and other (i.e., social, boat, and barnacle) ( 2=47.47, p =0.007). Limitations were placed on analyses when comparing species and size cl ass relationships for each type of injury due to the low occurrences of turtles found with each injury type and within each size class. Anthropogenic Injuries Boat propeller strike Nine turtles were found to have boat pr opeller strikes. Wound locations are discussed in a subsequent section discussi ng the results of boat propeller strikes from May 2000 through July 2004. Tar A juvenile E. imbricata was found to have tar on the anterior portion of its plastron (numerical region 7cd) and on th e ventral side of all four of its flippers (numerical regions 3cd, 4cd, 5cd, and 6cd). Fishing One known fishing related inju ry was found on a juvenile C. mydas with a deeply embedded fishing hook in its front left flippe r (numerical region 2d). Monofilament and sinker were attached to the hook at the time of hook removal. The turtle was observed for 1.5 hours before being released into the adjacent coastal waters. Non-Anthropogenic Injuries Shark A total of 12 C. caretta were found with shark-related injuries compared with zero shark-related injuries in C. mydas ( df =1, 2=10.3, p =0.0013). Four of the turtles were adult females, and the remaining eight tu rtles were juvenile s of unknown sex. Tooth

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45 impressions, crescent-shaped bite marks indi cative of sharks, and/or rake marks were found on the flippers and/or carapace and/or plastron on 11 of the 12 turtles determined to have been injured by a shark. The remaining turtle that lacked any of the previously mentioned injuries was missing a large crescent-shaped portion of the carapace (numerical region 2a) that extende d into the costal scutes. Social interactions Injuries resulting from social interacti ons among turtles were found only in adult C. caretta (n=5) and C. mydas (n=4). All turtles were classified in good body condition. Wound types consisted of circular bites found on the dorsal neck region of three C. caretta and one C. mydas , symmetrical abrasions found on the dorsal side of both rear flippers (regions 5abcd and 6cd) on one adult male C. mydas , and similar symmetrical abrasions found on the dorsal side of all four flippers (numerical regions 3b, 4b, 5bd, and 6bd) on one adult male C. mydas . One adult female C. caretta had symmetrical mating wounds on the ventral side of both front fli ppers (numerical regi ons 3d and 4d). Other injury types included two deep symmetrical creases expanding the entire plastron (numerical region 7abcd) on the adult male C. mydas discussed above with the symmetrical abrasions on all four flippers . Two of the individuals found with social related injuries were observed fighting in the canal the day of or prior to being captured. Both individuals were adult female C. caretta . One female sustained a cut above the left eye from fighting, while the other female su stained a cut on the head and a deep bite wound in the mouth region.

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46 Barnacle Two juvenile C. caretta and two juvenile C. mydas were found with superficial to deep depressions on the plastron or carapace (numerical regions 2c d and 7cd) resulting from barnacles of unknown species. Summary of Injury Locations A total of 858 injury loca tion records were found on the 511 captures between May through December 2000 (Table 3-4). The car apace region (numerical region 2abcd) accounted for 41.1% (n=353) of all injury loca tion records, whereas the cloaca/tail region (numerical region 8) had th e lowest with zero injury records (Table 3-4). Summary of Missing Regions of the Body Approximately 6.7 % (n=30) of the 448 indi vidual turtles had flipper amputations (Table 3-5). Of these, 53.3% (8 female: 8 unknown sex) were missing less than half of a flipper, 10.0% (1 female: 2 unknown sex) we re missing half of a flipper, 16.7% (3 female: 2 unknown sex) were missing over half of a flipper, and 20% (1 male:1 female: 4 unknown sex) were missing an entire flipper (Tab le A-1) . Results of the locations of the year 2000 flipper amputations (i.e., half thr ough entire flipper amputations) are discussed in a following section covering flipper amputations equal to or greater than half of one or more flippers May 2000 through July 2004. Turtles were found with missing “shaped’ sections (cres cent-shaped n=39, scalloped n=3, u-shaped marginal n=6, and v-shaped n=34) from their flippers and carapace, which were caused by an unknown injury source. May 2000 through July 2004 Boat Propell er Strikes and Flipper Amputations A total of 3,290 turtles (i ncluding recaptures) were captured during the 51-month period from May 2000 through July 2004. Of th ese, 80% (n=2,532) were classified as

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47 new captures, while 23% (n=758) were classifi ed as recaptures (i.e., captured >1 at the SLNPP during or prior to the study period). A total of 2,632 individual turtles comprising five species contributed to th e 3,290 captures (Table 3-6). Fig. 3-6 contains the size class distribution for each species. D. coriacea , E. imbricata , and L. kempii were removed from flipper amputation and boat propeller an alyses due to the relatively small numbers captured compared with C. caretta and C. mydas (no amputations or boat propeller strikes were found in these individuals). Flipper amputations (equal to or greater than half) A total of 3.1% (n=81) of the 2,632 indivi dual turtles were found to have equal to or greater than half of one or more of their flippers missing between May 2000 through July 2004. Body condition indices indicated th at 74.1% (n=60) of the 81 turtles had a body condition index of good, 23.4% (n=19) were in fair condition, 1.2% (n=1) was dead, and 1.2% (n=1) was in poor condition. Six turtles with original body condition indexes of good were later recaptured at which time body condition indexes were classified as good. A total of 72.8% (n=59) of the flipper amputations were found in C. caretta (52.8-98.8 cm SSCL, mean = 78.3 12.3 SD) of which 62.7% (n=37) were of unknown sex, 30.5% (n=18) were females, and 6.8% (n=4) were males. The remaining 27.2% (n=22) were C. mydas (25.9-87.2 cm SSCL, mean = 41.4 15.9 SD), which consisted of 21 turtles of unknown sex, and 1 fe male. Two of the 81 turtles were missing equal to or greater than half of two of thei r flippers. One individual was an adult female missing over half (>75% of both rear flippe rs) (sections 5abcd and 6abcd). The second was a juvenile of unknown sex missing both rear flippers (entire). The injury cause of 88.9% (n=72) of the 81 turtles with amput ations was unknown, however, the remaining 1.1% (n=9) were shark-related injuries. Se ven of the turtles with shark-related

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48 amputations were C. caretta (3 juveniles and 4 transiti onal) and two were juvenile C. mydas . Analysis indicate no significant difference (df=1, 2=1.03, p =0.3107) between the frequency of amputations found between species ( C. caretta 3.4% of 1761, C. mydas 2.6% of 842) ( p =0.3107). However, a significant difference was found between the overall percentages of amputati ons found among life stages (df=2, 2=24.32, p <0.0001). A total of 6.0% (n=21) of the 351 adults had amputations, 5.7% (n=21) of the 371 transitional turtles had amput ations, and only 2.07% (n=39) of the 1881 juveniles were found with amputations (Table 3-7). Further an alysis indicate a significant difference in the frequency of amputations found within th e three sex categories (male, female and unknown) (df=2, 2=12.17, p =0.002). A total of 6.1% (n=19) of the 312 females had flipper amputations, 7.7% (n=4 ) of males had amputations, and 2.6% (n=58) out of 2239 of unknown sex category had amputations (Table 3-7). Within-species analyses A significant difference was found between the percentages of amputations found among life stages of C. caretta (df=2, 2=27.4, p <0.0001). A total of 6.3% (n=20) of 316 adults, 6.21% (n=21) of 338 transitional, a nd only 1.63% (n=18) of the 1107 juveniles were found with flipper amputations. However, insufficient sample sizes restricted the ability to confidently co mpare life stages within C. mydas (i.e., 2.7% (n=21) of 744 juvenile C. mydas captured with amputations to the 2.86% (n=1) of 35 adults captured with amputations, and 0% (n=0) of the 33 transitional individu als). A significant difference was found among the percentages of amputations in males, females and those of unknown sex within C. caretta (df=2, 2=16.8, p =0.0002). A total of 6.2% (n=18) of 292 females were found with amputations within C. caretta , 11.4% (n=4) of 35 males,

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49 2.6% (n=37) of 1434 of unknown sex. Again, insu fficient sample sizes restricted the ability to confidently compar e differences in amputations among sex categories within C. mydas [i.e., 2.6% (n=21 of 805 juveniles capture d to 5.0% (n=1) of 20 females, and 0% (n=0) out of 17 males]. Location analyses The majority of amputations were found in C. caretta 72.3% (n=60) compared with the 27.7% (n=23) found in C. mydas . Overall flipper amputation location analyses (combined species data) indicate no significant statistical diffe rences in the following: 1) anterior versus posterior (front versus rear flippers), 2) an atomical location, or 3) side (left versus right). However, within species analyses indicate a significant difference in the number of amputations found in the front ri ght, front left, rear left, and rear right flipper (numerical region 3, 4, 5, and 6) ( 2 = 11.6, 0.01< p <0.001) within C. mydas . (the rear left and rear ri ght flippers each accounted for ~ 40% of the amputations within the species). A total of 35% (n= 21) of the amputations within C. caretta occurred in the front right flipper, however, this was not different statistically from the number of amputations found in the front left (df=1, 2=1.4, 0.5> p >0.1). Furthermore, anterior versus posterior (front versus rear flippers) analysis indi cate a significant difference within C. mydas with 22.7% (n=5) of the 22 amputa tions located in the front and 77.3% (n=17) in the rear flippers (df=1, 2=7.4, 0.01> p >0.005). No significan t difference was found in C. caretta with 58.3% (n=35) of the 60 amputations found in the front and 41.7% (n=25) located in th e rear flippers (df=1, 2=1.7, 0.5> p >0.1). Boat propeller strikes A total of 1.9% (n=49) i ndividual turtles were found with boat propeller strike injuries between May 2000 through July 2004. Body condition indices indicated that

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50 55.1% (n=27) had a body condition index of good, 36.7% (n=18) were in fair condition, and 8.2% (n=4) were in poor condition. A si gnificant difference was found in the number of boat strikes between species ( 2=7.4, p =0.0064). Eighty-six percent (n=42) of the propeller strikes were found in C. caretta (60.0-104.3 cm SSCL, mean = 79.0 12.74 SD) of which 54.8% (n=23) were of unknown sex, 35.7% (n=15) were females, and 9.5% (n=4) were males (Table 3-8). The remaining 14.3% (n=7) were C. mydas (28.1-69.1 cm SSCL, mean = 43.4 16.6 SD), which consisted of all juvenile turtles of unknown sex. A significant difference was found between the overall percentages of boat propeller strikes among life stages (df =2, 2=25.7, p <0.0001). A total of 4.6% (n=16) of the 351 adults, 3.5% (n=13) of the 371 tran sitional, and only 1.06% (n=20) of the 1881 juveniles were found with boat propeller strikes. Fu rther analysis indicate a significant difference in the frequency of amputations f ound within the three sex categories (i.e., male, female and unknown) (df=2, 2=27.5, p <0.0001). Of the 312 females, 4.8% (n=15) had boat propeller strikes, 7.7% (n=4) of th e 52 males, and 1.3% (n=30) of the 2239 of unknown sex had boat propeller strikes. Within-species analyses A significant difference was found between the percentages of boat propeller strikes among life stages of C. caretta (df=2, 2 =19.8, p <0.0001). Within C. caretta , 5.1% (n=16) of 316 adults, 3.8% (n=13) of 338 transitional, and only 1.2% (n=13) of the 1107 juveniles were found with boat propeller st rikes. However, insufficient sample sizes restricted the ability to confid ently compare life stages within C. mydas [i.e., 0.9% (n=7) of 744 juvenile C. mydas captured with propeller strikes co mpared to 0% (n=0) of the 35 adults and 33 transitional individuals]. A significant di fference was found between the percentages of boat propeller strikes among sex classes of C. caretta (df=2, 2=25.6, p <0.

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51 .0001). A total of 5.1% (n=15) of 292 females, 11.4% (n=4) of 35 males, and 1.6% (n=23) of 1434 of unknown sex were found with boat propeller strikes. Again, insufficient sample sizes restricted the ability to confidently compare differences in boat propeller strikes within sex of C. mydas [i.e., 0.9% (n=7) of 805 juveniles captured to 0% (n=0) out of 20 females and 17 males]. Location analyses A total of 57 boat slice records were compiled from the 49 turtles with boat propeller strikes. Of the 57 slice records, 83% (n=48) were found on the carapace, 10.3% (n=6) on the head, 3.4% (n=2) on the plastron, 1.7% (n=1) on the neck, and 1.7% (n=1) on the rear left flipper. Injury condition c onsisted of the following: 46.5% (n=27) healed, 32.3% (n=19) partially h ealed, 5.2% (n=3) fresh, and 15.5% (n=9) were unknown. Subregional analysis indicates a significan t difference between the location of propeller strikes on the anterior and posterior regi ons of the carapace (subregion 2cd and 2ab, respectively) (Table 3-9). A total of 48.8% (n=20) C. caretta were found with propeller strikes within the anterior region of the carapace (subregion 2cd) compared to 100% (n=7) of the C. mydas (df=1, 2=6.4, p =0.0116). Further analyses within C. caretta indicated no significant differe nces among life stages and the location of injury. A total of 85.37% (n=35) C. caretta were found with propeller strike s within the posterior region of the carapace (subregion 2ab) compared to 42.9% (n=3) of the C. mydas (df=1, 2=6.5, p =0.0105). The sample size for C. mydas was too small to analyze statistical differences among life stages for both the posterior and an terior regions of the carapace. Closer examination of frequency of propeller strikes within subregions of the carapace (i.e., A, B, C, or D) indicate that C. caretta are injured significantly more within subregion A than

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52 C. mydas, 70.7% (n=29) of 41 C. caretta compared with 28.6% (n=2) of 7 C. mydas (df=1, 2=4.6, p =0.0311). Conclusion The injury assessment data presented in th is project is based on turtles entrained within the SLNPP intake pipes. Therefore, observed injuries are recorded from turtles that have survived injuries or have not b een previously injured. This project provides information for five species of live sea tur tles utilizing the nearshore waters of the Atlantic Ocean. In general, it is was difficult to ascertai n species, size class, or sex association within injury types and causes due to signi ficant differences in the predominant size classes for each of the species. The turtle s captured at the SLNPP were predominantly small juvenile green turtles, and large juveni le and adult loggerhead turtles (Fig. 3-2 and Table 3-1). The majority of loggerhead turtle s captured at the SLNPP were within the upper size classes (>60 cm SSCL), whereas the ma jority of the green turtles were within the smaller size classes <60 cm SSCL) (F ig.3-2). The overall body condition of the turtles was good (96.1%, n=491, Fig. 3-4). Details for each injury cause (i.e., barnacle, tar, fishing, social, boat propeller strike, and shark) recorded during May through Decem ber, 2000 can be found in Table B-1 (i.e., anatomical and numerical location, view, type, depth, and recency of the injury). Injury types that were not found in this project or were found in low frequencies, could be interpreted to mean that the intensity of the injury source is zero, or the injury source leads to 100% mortality (Schoener 1979). Ho wever, without knowing both the injury and survival frequencies, the ecological and bi ological pressure placed on a species by an injury source is unknown (Schoener 1979). Injuri es related to tar, fishing, and barnacles

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53 were all found in low frequencies (Table 3-2). Unfortunately, it is no t known if the data accurately represents the pressure of each s ource (i.e., tar, fishi ng, and barnacles) on the sea turtles utilizing the nearshore waters of th e SLNPP, or if there are other explanations for such findings. For example, fishing relate d injury sources may be placing medium to high impacts on sea turtles, however, such injuries (e.g., punctures, deep cuts, and strangulation wounds) may not be possible to identify if the injury source (e.g., fishing line or hooks) are no longer present. Future injury data should be compiled and analyzed at the SLNPP and elsewhere, in order to unde rstand the injury impacts such sources may be having on sea turtle populations. Shark-related injuries were found only w ithin loggerhead turtles >67 cm SSCL (n=12), which supports previous findings by Heithaus et al . (2002), which concluded that loggerheads are found with highe r rates of shark-inflicted in juries than green turtles ( p =0.0013). Alternatively, the data from this study could suggest th at loggerheads are able to survive shark-related attacks whereas green turtles do not survive shark attacks. Heithaus et al. (2002) conclude d that male loggerhead turtle s may incur higher rates of shark-inflicted injuries than female loggerhead turtles, male green turtles, and female green turtles due to their possible engageme nt in higher risk activities. This study was unable to support or refute such findings due to insufficient sample sizes of ‘known’ sexclass (i.e., only 4 females and 8 individuals of known sex ere f ound with shark-related injuries). However, some biological impor tance may exist in that no male turtles (loggerhead or green turtles) were among the 12 turtles determined to have shark-related injuries.

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54 Furthermore, it was difficult to assess si ze class associations due to the significant differences in the mean size class of captured loggerhead ( n = 243, mean = 79.0 13.1 SD) and green turtles (n=203, mean = 46.3 19.6 SD) (Table 3-1). No turtles smaller than 67 cm SSCL were captured with sharkrelated injuries, which may indicate that turtles in smaller size cl asses are unable to survive shark-in flicted injuries and/or they are small enough to be consumed whole by a shar k as stated by Heithaus et al. (2002). The latter scenario leaves zero probability of survival. One significant difference that may influen ce the injury data presented in this study and that by Heithaus et al. ( 2002) is the differences in cap ture methodologies. In this study, turtles are entrained into the intake pi pes within the nearshore system (see Chapter 2 for details), whereas Heithaus et al. used the ‘rodeo’ technique. This method involves spotting turtles in the water from a boat, a nd a person jumping off the bow of the boat to capture the turtle. Injuries relating to social interaction were found in five adult loggerhead turtles and 4 adult green turtles. One very interesting injury type wa s the symmetrical creases found on the plastron of an adult male green tu rtle (no such wounds were found in male loggerhead turtles in this study). To the au thor’s knowledge, no such injury has been previously reported in the literature. The creas es may be the result of the plastron bending to fit closely against the female’s carapace, which may ease his ability to properly clasp onto the marginals with the claws located on his front and rear flippers (Ernst et al. 1994), which may lengthen the duration of copulat ion by increasing the hydrodynamics of the mating pair. In other words, if the male is secured tightly to the female, there is less chance of them becoming separated during the copulatory process. Symmetrical wounds

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55 found on the dorsal side of the front and rear f lippers of two male green turtles were also of interest. It is unknown if these wounds resu lt from the pre-copul atory process between the male and female, or if the wounds are th e result of aggressive biting from other males before or during the copulatory process be tween the male and female mating pair. The percentage of turtles (3.1%) sustaini ng flipper amputations compared to the total number of individual tur tles captured (n=2,632) at the SLNPP was relatively low. This may indicate that turtles that sustai n flipper amputations have lower survival probabilities. A turtle missing a flipper may be less likely to escape predation, forage properly, as well as successfully complete repr oductive processes. The turtles that were captured at the plant with flipper amputations consist mostly of transitional and adult turtles. This follows the logic that as a function of time, a higher number of non-lethal, permanent injuries would be found in the larger size/age classes. In this study, no statistica lly significant differences were found in the number of amputations recorded for each of the species (loggerhead and green turtles). Within loggerhead turtles, a higher proportion of am putations were found in the front flippers (58.3%) than in the rear flippe rs (41.7%) (Fig. 3-7). This wa s statistically non-significant, however, there may be some biological signifi cance in this finding. It may be suggested that in projects only applying a si ngle tag to a turtle that the tag not be placed in the front right flipper based on the higher rates amputa tion rates associated with this limb in loggerhead turtles. Furthermore, the inju ry data from the time period of May through December 2000 indicate that the neck region may be a more advantageous region of the body for PIT tag placement compared with the front right flipper. A total of 18 injury records (2.1%) were found in the neck region compared with 41 injury records (4.8%) in

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56 the front right flipper (Table 3-4). Placement of PIT tags in the neck region may increase tag retention rates and the ability to identif y individual turtles in subsequent captures, which could be especially important in re search programs where placement of a single PIT tag (and no external tags) is standard. Conversely, the rear flippers in green turtles (77.7%) ac counted significantly for the majority of the amputations found within the species (Fig. 3-8). Such differences in the location of the amputation between species inci te several questions. Are the differences a result of behavioral factors between loggerhead and green tu rtles such as a ‘fight’ or ‘flight’ response? Perhaps green turtles have evolved a flight response (e.g., quick speed and maneuverability) to predat ors. For example, if a predatory shark approached a green turtle, the turtle would swim rapidly away from the pred ator, and thus leaving the posterior end of the body (e.g., the rear flippers) exposed to in jury. If loggerhead turtles have evolved a more fight behavior response, this may be one expl anation for the higher amputation rates in the anterior body regi on of the species. Logge rheads, unlike green turtles, are not known for speed and agilit y. Instead, these turtle s are better known for their large head size compared with the rest of their bodies, powerful crushing jaws and reduced speed compared with other turtle species. Loggerh ead turtles may have a higher likelihood of survival if they fend-off predat ors by using their powerful jaws to inflict injury upon their predator. Both species have been observed to avoid being grasped by predators by maneuvering their carapace or plastron within a vertical plane towards predators (Marquez 1990; Heithaus et al. 2002). Abiotic threats such as fishing line may impact one species compared to another based on their flipper functions. Loggerhead turtles have been reported to use their front

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57 flippers when ‘mining’ for food (Preen 1996). No such behavior has been noted in green turtles. This behavior may subject them to increased threats (e.g., fishing line, hooks, and contaminants) that have settled into the bent hic zone over time. Clearly, more data should be collected in order to answer such questions. It is evident that sea turtles may lose one or more of their flippers in their lifetime. The question that remains is how the partial to complete loss of a flipper is impacting their ability to function (e.g., propelling and steering through the water, foraging, predator avoidance, and reproductive fitness) . For example, are males that are missing flippers less fit than males with no flipper loss when competing for females on the mating grounds (i.e., reduced fitness)? Is a male with a front or rear fli pper amputation able to properly grasp onto a female during copulati on, especially if there are several males attacking him (e.g., biting at his flippers) du ring the process? The long-term reproductive effects of flipper loss in adult females ar e better understood. Female s that are missing the scooper portion of their rear fli ppers are unable to dig a proper egg chamber (Miller et al. 2003), which reduces her reproductive ability. Unfortunately, unlike other injuries that may subside with time, the loss of a flipper is a permanent injury that affects the sea turtle for the remainder of its life. Understanding how many turtles are undergoing the plight of flipper loss, as well as identifying the causes of such injuries may he lp reduce the number of turtles that sustain such injuries in the future. The boat propeller injury data from this project prompts several questions. The data suggests that loggerhead turtle s are hit more frequently by boat propellers than green turtles. The results could also be interprete d that greens are hit more frequently than loggerheads, but do not survive the strikes. Fu rther leading to ques tions related to the

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58 locations of the boat propeller strikes on the body. The data suggests a trend that loggerheads are hit more frequently in the pos terior ends of their carapace compared to greens in the anterior ends (specifically s ubregion 2a, refer to Fi g. 2-3). It could be suggested that injuries located in one end versus the ot her could be linked to higher or lower survival rates a ssociated with certain regions of the body. However, if rate of survival is not responsible for the differen ces in the frequency of strikes found between the posterior and anterior end, it could attri buted to behavioral differences between the two species (just as it could be for the differences in the fr equency of flipper amputations and other injury sources and types). As previously stated, green turtles are ge nerally referred to as being faster than loggerhead turtle (i.e., greater escape ability). If a loggerhead turtle and a green turtle were positioned at the waters surface equal distance from an oncoming boat, it is reasonable to suggest that the green turtle w ould respond faster than the loggerhead turtle. This is assuming that each turtle would res pond the same way such as diving vertically down into the water. Due to the lack direct observations between boats and sea turtles, the detection time and behavi or response(s) of turtles is largely unknown. One or both species may initially move parallel to the surface for a period of time before diving, which may be one explanation as to why green turtles may be hit more frequently in the anterior portions of their body (e.g., time at the waters surface attempting to ‘out swim’ the boat). Further, loggerhead turtles may have a longer re sponse time (i.e., decreased escape ability) compared to green turtles, and thus may be why they are hit more frequently in the posterior end of the carapace.

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59 Female n=97 40% Male n=3 1% Unknown n=143 59% Caretta carettan=243 54.2%Eretmochelys imbricatan=2 0.4%Chelonia mydasn=203 45.3% Unknown n=186 92% Male n=9 4% Female n=8 4% Male n=0 0% Female n=0 0% Unknown n=2 100% Figure 3-1. Species ( Caretta caretta , Chelonia mydas , and Eretmochelys imbricata ) and sex composition (male, female and unknown sex category) of the individual turtles (n=448) captured May thr ough December 2000 at the SLNPP.

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60 2 226 160 33 930 50 100 150 200 250 300 CCCMEISpeciesNumber of captures Recaptures New Recruits Figure 3-2. Total number of recaptures and new recruits for Caretta caretta (CC ) , Chelonia mydas (CM), and Eretmochelys imbricata (EI) May through December 2000.

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61 Year 2000 Size Class Distribution n=4482 11 61 60 5 32 61 55 23 6 3 12 4 11 57 47 7 0 10 20 30 40 50 60 7020-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 100-109Straight standard carapace length (cm)Number of turtles CC CM EI Figure 3-3. Size class distribution of Caretta caretta (n=243), Chelonia mydas (n=203) and Eretmochelys imbricata (n=2) captured May through December 2000 at the SLNPP.

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62 Body Condition n=511 13 11 2 1 2 2 000 244 2450 50 100 150 200 250 300 GoodFairPoorDead Body conditionNumber of turtles CC CM EI Figure 3-4. Proportion of turtles (n=511, captu res and recaptures) found within each body condition (good, fair, poor, and dead) captured May through December 2000 at the SLNPP.

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63 Unknown n=288 45% Intake Pipe n=250 39% Uninjured n=72 11% Shark n=12 2% Boat Propeller n=9 1% Fishing n=1 0% Tar n=1 0% Barnacle n= 4 1% Social n= 9, 1% Figure 3-5. Proportion of injury causes f ound on the 511 turtles cap tured May through December 2000. Individuals may have multiple injury causes.

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64 Size Class Distribution May 2000 July 2004 n=3,2900 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 100-109 >110Straight standard carapace length (cm)Number of captures CC CM DC EI LK Figure 3-6. Size class distribution of Caretta caretta (n=1875), Chelonia mydas (n=1386), Dermochelys coriacea (n=8), Eretmochelys imbricata (n=17), and Lepidochelys kempii (n=4) captured May 2000 th rough July 2004 at the SLNPP (includes recaptures).

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65 Figure 3-7. Frequency of flipper amputations divided by numerical regions (3, 4, 5, and 6) within Caretta caretta (males, females and unknown sex categories). Front right flipper (region 4)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Entire Over half Half Front left flipper (region 3)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Rear left flipper (region 5)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Rear right flipper (region 6)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations

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66 Figure 3-8. Frequency of flipper amputations divided by numerical regions (3, 4, 5, and 6) within Chelonia mydas (males, females and unknown sex categories). Front right flipper (region 4)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Entire Over hal f Half Front left flipper (region 3)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Rear right flipper (region 6)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations Rear left flipper (region 5)0 2 4 6 8 10 12 14 MalesFemalesUnknown SexNumber of amputations

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67 Table 3-1. Species, size range, mean standa rd deviation of the 448 individual turtles captured May through December 2000 at the SLNPP. Species Size range Straight standard carapace length (cm) X SD Caretta caretta ( n =243) 47.4-103.1 79.0 13.1 Chelonia mydas ( n =203) 26.2-106.8 46.3 19.6 Lepidochelys kempii ( n =2) 48.0-50.6 49.3 1.8 Table 3-2. Overview of all injury caus es found within each species May through December 2000. Injury Cause Caretta caretta Chelonia mydas Eretmochelys imbricata Total Tar 0 0 1 1 Boat Propeller Strike 7 2 0 9 Fishing 0 1 0 1 Shark 12 0 0 12 Social 5 4 0 9 Barnacle 2 2 0 4 Unknown 116 172 0 288

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68 Table 3-3. Injury type records (n=858) found on the 511 turtles captured May through December 2000. Table 3-4. Injury location reco rds (anatomical region) with and without intake pipe related injuries found on the 511 turt les captured May through December 2000. Injury Type Number of Injury Type Records Percentage of Records Abrasion 6 0.7% Amputation 31 3.6% Bite 29 3.4% Broken 1 0.1% Crack 3 0.3% Crease 1 0.1% Cut 19 2.2% Depression 19 2.2% Discoloration 17 2.0% Hole 2 0.2% Missing 40 4.7% Missing (crescent-shaped) 41 4.8% Missing (marginal) 7 0.8% Missing (scalloped) 3 0.3% Missing (u-shaped notch marginal) 6 0.7% Missing (v-shaped) 34 4.0% Other 30 3.5% Puncture 2 0.2% Raised 2 0.2% Rake marks 1 0.1% Scrape 555 64.7% Slice 9 1.0% Total 858 100.0% Injury Location Number of Injury Location Records (with intake pipe related injuries) Percentage of Records Number of Injury Location Records (without intake pipe related injuries) Percentage of Records Head 112 13.1% 16 3.2% Carapace 353 41 .1% 154 30.7% Front Left Flipper 48 5.6% 43 8.6% Front Right Flipper 41 4.8% 40 8.0% Rear Left Flipper 43 5.0% 43 8.6% Rear Right Flipper 40 4.6% 37 7.4% Plastron 190 22.1% 144 28.7% Cloaca/Tail 0 0.0% 0 0.0% Left Eye 5 0.6% 2 0.4% Right Eye 3 0.3% 2 0.4% Mouth (Jaws/Esophagus) 5 0.6% 5 1.0% Neck 18 2.1% 15 3.0% Total 858 100.0% 501 100.0%

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69 Table 3-5. Flipper amputation results May th rough December 2000 (less than half, half, over half, and entire) within species ( Caretta caretta , Chelonia mydas , and Eretmochelys imbricata ) and sex class (male, female and unknown sex). Table 3-6. Species, size range, mean standard deviation of 3,290 turtles captured at the SLNPP from May 2000 through July 2004. Table 3-7. Percentage of turtles found with amputations within each life stage (adult, transitional, and juvenile) and sex category (male, female, and unknown). Species Degree of Flipper Loss #of Males # of Females #of Unknown Sex/Total Less than half Half Over half Entire Total Caretta caretta 0-8-2 10 0-1-1 2 0-3-2 5 1-1-1 3 1-13-6 20 Chelonia mydas 0-0-7 7 0-0-1 1 0-0-0 0 0-0-3 3 0-0-11 11 Eretmochelys imbricata 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 Total 0-8-9 17 0-1-2 3 0-3-2 5 1-1-4 6 1-13-17 31 Species Size range Straight standard carapace length (cm) X SD Caretta caretta ( n =1,875) 47.4-104.3 71.0 11.4 Chelonia mydas ( n =1,386) 18.7-108.3 43.0 14.3 Dermochelys coriacea ( n =8) 122.9-152.7 136.4 11.3 Eretmochelys imbricata ( n =17) 35.9-78.3 54.5 11.4 Lepidochelys kempii ( n =4) 38.2-61.4 51.4 9.7 Life Stage Amputation Sex Category Amputation Adult (n=351) 6% Male (n=52) 7.7% Transitional (n=371) 5.7% Female (n=312) 6.1% Juvenile (n=1881) 2.1% Unknown (n=2239) 2.6%

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70 Table 3-8. Percentage of turt les found with boat propeller strikes within each sex category (male, female and unknown). Species Sex Category Male Female Unknown Caretta caretta (n=42) 9.5% 35.7% 54.8% Chelonia mydas (n=7) 0% 0% 100% Table 3-9. Percentage of turtles of each sp ecies found with boat pr opeller strikes within the anterior and posterior subregion of the carapace. Species Anterior subregion 2cd Posterior subregion 2ab Caretta caretta (n=42) 48.8% 85.4% Chelonia mydas (n=7) 100% 42.9%

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71 CHAPTER 4 INTAKE PIPE RELATED INJURIES Background Since opening in 1976, the SLNPP has signi ficantly reduced potential impacts on the turtles inadvertently entrained into the f acility by maintaining a vigilant sea turtle monitoring program (Quantum Resources 2005 ). However, observations over the past several years have shown that turtles are sust aining fresh scrapes and cuts while traveling through the intake structures at the plant (Q uantum Resources 2005). In addition, there is rising concern that the frequency and location of the fresh injuries may be negatively impacting the turtles. Such impacts, whethe r they are short or long-term, are not wellunderstood. Unfortunately, in 2003 a turtle died from injuries sustained while traveling through the pipes, an exampl e that suggests a growing problem (Quantum Resources 2004). The fresh scrapes found on the turtles were assumed to occur as a consequence of encountering biofouling (e.g., epibionts such as barnacles) within the intake pipes, which have not been cleaned since the early 1980’ s (M. Bresette, Quantum Resources, pers. comm. 2005). The accumulation of such objects (abiotic and biotic) increases water velocity as well as providing additional substrate for epibionts to colonize, thereby increasing the number of objects the turtles may encounter while traveling through the pipes. One assumption in this study is that tu rtles traveling at a ra te of 4-7 ft/second are unable to actively avoid obstacles within the intake pipes, which may lead to the minor /severe physical trauma referred to as fresh sc rapes. In general, fresh scrapes are open

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72 wounds that may allow pathogens to enter the body that could lead to infections. At the SLNPP, turtles that are captur ed and sick or injured are tr eated, and when necessary are held for observation before being released (Quantum Resources 2005) . Turtles requiring further medical evaluation/treatment are sent to an approved rehabilitation facility after contact with the Florida Fish and Wildlife Conservation Commission (FFWCC) (Quantum Resources 2005). Methods Study Period and Objectives Fresh scrapes were evaluated at the SLNPP for a total of 18 months [3-month time periods (May through July) spanning acr oss six years (2000 through 2005)]. The time period of May through July was selected be cause it provided the longest continuous block of time within each of the years w ithout the data being compromised by natural and/or anthropogenic factors. Two primary fact ors that narrowed the time-frame in this study were 1) The disturbance of normal plan t operation during late summer/fall of 2004 resulting from the hurricanes that impacted the southeastern United States, and 2) Modifications in the sea turtle research st aff the SLNPP before May 2000. The core sea turtle research staff (those employed year-r ound) at the SLNPP has remained stable from May 2000 through July 2005 with the exception of one new hire during 2005. The new hire was considered ‘in-traini ng’ and was largely overseen by senior research members. The data utilized represent consistent 3-month time blocks during the summer months across six years (2000 through 2005). Ther efore the results prov ided in this study may not accurately reflect intake pipe related fresh scrapes for the fall and winter months of 2000 through 2005. Potentially important differences may exist between the sampling periods (May through July) in this study and the excluded months. For example, the mean

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73 size classes captured at the SLNPP vary among seasons. The mean size for turtles captured May through July 2000 to 2005 was 66.8 cm SSCL, but the m ean size for turtles captured August through April 2000 to 2005 wa s 55.5 cm SSCL (M. Bresette, Quantum Resources, pers. comm. 2005). On average, high er percentages of juvenile green turtles are captured during the winter than in the su mmer (Quantum Resources 2005). If smaller turtles are less severely impacted by fresh scrape s, the overall percentage of turtles being impacted by fresh scrapes during the winter m onths may potentially be less than what is found in this study that examines only the summer months May through July. Again, this study did not utilize all captures for each year because of the aforementioned natural and anthropogenic factors. Another important temporal factor that may alter fresh scrape impacts is the potential fluctuation in wate r temperature among seasons. This may affect the level of biofouling within the intake pi pes as lower water temperatures may not be optimal for growth of certain ep ibionts such as barnacles. Fresh scrape frequency and severity was evaluated for May through July 2000, 2002, and 2004. The severity of the intake pipe related scrapes was determined by the location of each fresh scrape on the body [r efer to methods and Sea Turtle Injury Identification System (STIIS) in Chapter 2] and degree of scale/scute and flesh removal (i.e., superficial or deep). Furthermore, fresh scrape frequency was evaluated May through July 2001, 2003, and 2005. It is unknown if species characteristics (e.g., speed, alertness, maneuverability) may significantly influence travel time or ability to avoid obstacles while traveling through the intake pipe s. It is possible that differences in fresh scrape frequency between species may act ually be due to size class differences.

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74 Project objectives: OBJECTIVE 1. Determine whether any trend ex ists in the frequency of fresh scrape occurrence May through July 2000 to 2005. OBJECTIVE 2. Identify and quantify fresh scrape locations within each of the primary body regions (May through July 2000, 2002, and 2004). OBJECTIVE 3. Compare presence/absence of fresh scrapes among species and size classes (May through July 2000 to 2005). Statistical Analyses A standard normal z-test was used to dete rmine if fresh scrape frequency increased from May 2000 through July 2005. A nave chi-s quare statistical te st in statistical program SAS version 9.1 was used to test fo r significant differences in the number of turtles found with fresh scrapes among y ears, species, and size classes. Results May through July 2000 to 2005 Figures 4-1 and Fig. 4-2 provi de the total number of tur tles captured within each species ( C. caretta , C. mydas , D. coriacea , and E. imbricata ) and size class during May through July 2000 to 2005. Fresh scrape fre quency increased significantly from May 2000 through July 2005 ( df =1, z =-9.89, p <.001) (Fig. 4-3). Compar isons of fresh scrape occurrence between species ( C. caretta and C. mydas ) indicate a significant difference during 2002, 2003, and 2004 ( p <.0001). However, no significa nt differences were found between species for the years 2001(n=131, 2=.7553, p =.3848) and 2005 (n=413, 2=2.14, p =.1432, n=413). It was of further interest to test for differences among size classes while ignoring species. All year s showed a significant difference in the percentage of fresh scrapes found among size classes ( p <.0001), except 2001 ( 2=10.8, p <.0962) (Table 4-1, Fig. 4-4). In addition, fr esh scrapes have steadily increased within

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75 smaller size classes with each consecutive ye ar. For example, fresh scrape occurrence within the <40 cm SSCL size class increased from 27.8% (n=36) in 2000 to 58.3% (n=36) in 2005 (Table 4-1). Overall, the number of turt les exhibiting fresh scrapes has significantly increased from May 2000 to July 2005. However, it can not be determined definitively if the increase is a function of species, size or both, due to the large variation among size classes between the two species (i.e., pr edominantly small juvenile green turtles compared to large juvenile/adult loggerhead turtles). Fresh scrape body region analysis (May through July 2000, 2002, and 2004) Fresh scrape severity was examined fo r the time period of May through July 2000, 2002, and 2004. During this period 95.6% (610 out of 638) of all fresh scrapes recorded were superficial (Table 4-2). For all years, fresh scrapes occurred predominantly within the carapace and anterior regions of the body (Fig. 4-5). A total of 94% (600 out of 638 fresh scrape records) of fresh scra pes during 2000, 2002, and 2004 occurred on the carapace, head, and plastron regi ons. Fresh scrape records w ithin the eye region increased by 81.2%, from a combined total of th ree during 2000 and 2002, to 16 in 2004. In addition, three records were found in the m outh region in 2004 compared to zero during 2000 and 2002. Subregional carapace analyses showed that 95.3% (n=107), 90.5% (n=116), and 94.4% (n=144) of the scrapes found on the carap ace were found in the anterior subregion 2c and/or 2d in 2000, 2002, and 2004, respec tively. Subregional plastron analyses showed that 81.8% (n=22), 80.0% (n=20), and 78.8% (n=33) were found in the anterior subregion 7c and/or 7d in 2000, 2002, and 2004, respectively.

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76 Conclusion The number of turtles found to have fres h scrapes has significantly increased (p<.001) from 51% in 2000 to 86% in 2005 (Fig. 43). The data indicate that as of July 2005, fresh scrapes are found on >50% of all captures within each of the 10-cm size classes at the SLNPP (Fig. 4-4 and Table 41). Furthermore, a general increase was found in fresh scrape frequency within smaller size classes (<80 cm SSC L) with each year, which implies that the occurrence of fresh sc rapes is not limited to only larger turtles (adults). These findings may infer that the biof ouling within the intake pipe has steadily accumulated with each year. It can be furt her postulated that as of July 2005, the accumulation has reduced the diameter of the intake pipe (at one or more sections) to the degree where only turtles less than 40 cm SSCL have a 40% probability of being entrained and not sustaining fresh scrapes co mpared to turtles greater than 40 cm SSCL that have less than a 11.5% probability of en trainment and not sustai ning fresh scrapes. A significant contribution of this study is the exhaustiv e detail and insight it has provided into the location of each fresh scrape on turtles captured at the SLNPP during May through July from 2000, 2002, and 2004 (F ig. 4-5). Fresh scrape location was quantified and statistically evaluated within the major body regions. This fine-scale examination was necessary in order to fu lly and accurately understand where fresh scrapes were occurring on the body, and to fu rther test for significant increases within body regions (particularly within vital organs such as the eyes). Among the findings in this study were significant increases of fres h scrapes within the eye and overall head region. For example, fresh scrape records with in the eyes increased by 81.2% from three records in 2000 and 2002 to 16 records in 2004.

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77 Future research should include data from the winter/fall months during years when the data was not compromised due to natural or anthropogenic factors. While this study may not give a complete picture of the pot ential impacts of fresh scrapes during the winter/fall months at the SL NPP, the data utilized represent a systematic comparison across six years of sampling w ithin identical 3-month time blocks (May through July). Further, the analyses included sufficient captu re data within each si ze class in order to complete valid statistical comparisons, which allows for introspect into fresh scrape impacts in juveniles among smaller size classes. The results from this study support some of the concerns previously expressed by the core sea turtle research staff at the SLN PP about cleaning of the intake pipes in order to reduce entrainment impacts on the sea tu rtles captured at the facility. Plans are currently underway that incl ude cleaning the intake pipes, as well as placing grates around the intake structures that would poten tially exclude 25% of the turtles captured (the adults) at the SLN PP (M. Bresette, Quantum Resources, pers. comm. 2005). The findings and information provided in this study may bene fit those (both sea turtles and humans) beyond the southeastern United States. For example, the data now available as a result of this study may pr ovide much-needed information to nuclear electric generating facilities across the globe where potential sea turtle interactions may now exist, or in the future. The majority of s ea turtles are highly migratory, and as marine systems are modified via natural and anth ropogenic factors, sea turtles may undergo small/large scale behavioral shifts that may involve utilization of previously uninhabited areas. Monitoring and continuous re-evaluati on of capture methodologies and protocols

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78 at such facilities may reduce and ultimately eliminate such negative impacts on sea turtle populations.

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79 157, 61% 161, 80% 103, 39% 96, 72% 35, 26% 1, 1% 107, 57% 77, 42% 134, 62% 83, 38% 39, 20% 249, 61% 163, 38% CC CM DC EI 2000 2001 2002 2003 2004 2005 Figure 4-1. Percentage of each species Caretta caretta (CC), Chelonia mydas (CM), Dermochelys coriacea (DC), and Eretmochelys imbricata (EI) captured May through July 2000 to 2005.

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80 Number of Captures within each size class 45 19 21 49 72 20 12 8 24 11 30 29 39 19 31 18 70 14 20 21 13 79 22 34 47 43 87 59 105 18 36 25 31 20 16 19 55 20 16 16 35 36 0 20 40 60 80 100 120<40 40-49 50-59 60-69 70-79 80-89 >90Straight standard carapace length (cm)Number of captures 2000 2001 2002 2003 2004 2005 Figure 4-2. Size class distribution for each year May through July 2000 to 2005.

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81 86% 79% 68% 74% 60% 51% y = 0.0654x 130.22 R2 = 0.8973 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 19992000200120022 003200420052006 YearPercent Figure 4-3. Proportion of turtles found with fresh scrapes May through July, 2000 to 2005.

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82 <40 40-49 50-59 60-69 70-79 80-89 >90 2000 (n=260) 2001 (n=131) 2002 (n=184) 2003 (n=217) 2004 (n=200) 2005 (n=413) 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 Percent Straight standard carapace length (cm) Year Figure 4-4. Fresh scrape occurrence within size class May through July, 2000 to 2005.

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83 Fresh Scrape Location Year 2000, 2002, & 2004 57% 12% 27% 1% 58% 28% 10% 2% 1% 58% 20% 6% 2% 13% 1% .4% Carapace Head Plastron Front Flippers Eyes Neck Rear Flippers Mouth 2000 2002 2004 Figure 4-5. Proportion of fresh scrapes found within each body region May through July 2000 (n=185 records), 2002 (n=201 r ecords), and 2004 (n=252 records). Table 4-1. Percentage of each size class w ithin each year (May through July, 2000 to 2005) found with fresh scrapes. Number in parenthesis represents the total number of turtles captured in each size class per year. Year Size class Straight standard carapace length (cm) <40 40-4950-5960-6970-7980-89 >90 2000 (260) 27.7% (36) 24.4% (45) 36.8% (19) 33.3% (21) 72.2% (18) 71.4% (49) 68.1% (72) 2001 (131) 65.0% (20) 58.3% (12) 62.5% (8) 50.0% (24) 36.4% (11) 48.0% (25) 80.7% (31) 2002 (184) 53.3% (30) 62.1% (29) 81.3% (16) 79.5% (39) 68.4% (19) 85.0% (20) 90.3% (31) 2003 (217) 36.6% (55) 77.8% (18) 79.0% (19) 77.1% (70) 71.4% (14) 85.0% (20) 85.2 (21) 2004 (200) 37.5% (16) 76.9% (13) 75.0% (16) 78.5% (79) 77.3% (22) 90.0% (20) 97.1 (34) 2005 (413) 58.3% (36) 85.1% (47) 86.0% (43) 78.4% (87) 88.6% (35) 98.3% (59) 94.3% (105)

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84 Table 4-2. Percentage of fresh scrapes within each severity class (superficial and deep) May through July, 2000, 2002, and 2004. Numb er in parenthesis represents the total number of fresh scrape records turtles captured within each size class per year. Year (Number of fresh scrape records) Fresh scrape severity Superficial Deep 2000 (n=185) 99% 1% 2002 (n=201) 97% 3% 2004 (n=252) 92% 8%

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85 CHAPTER 5 SUMMARY AND CONSERVATION SIGNIFICANCE Foremost, this project provides details of injury related to anthropogenic and natural sources found within se a turtles utilizing the neritic zone of the southeastern United States. Conservation of sea turtle spec ies demands the identification of both lethal and non-lethal threats across the various species, life stag es, and sex classes. The short and long-term impacts of non-lethal injuri es on sea turtles are poorly understood. The percentage of turtles survivi ng to adulthood is often of extr eme interest when assessing sea turtle populations. Although th e survival to reproductive ag e is essential to the longterm health of sea turtle populations, the repr oductive fitness of the surviving animals is as equally important. Does it matter if a turtle survives to adulthood if it cannot reproduce due to a physical handicap resulti ng from a prior injury event? In this study, a systematic Sea Turtle Injury Identification System (STIIS) was created and applied to asse ss several thousand sea turtle s captured at the St. Lucie Nuclear Power Plant (SLNPP). The STIIS can be applied globally across research and stranding projects assessing both live and dead sea turtles. Prior to this project, no known method existed that allowed for such detail ed injury identifica tion, documentation, and statistical analyses. Using this system, de tails of each injury (type, cause, condition, depth, location etc.) can be formatted into a database where it can easily be quantified and analyzed. The STIIS has allowed for consistent injury assessment of the sea turtles captured at the SLNPP, which has in turn allowed fo r a better understanding of the overall injury

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86 condition of the turtles utili zing the nearshore system. Th e STIIS has provided an essential framework from which to work wh ile attempting to identify not only injury types and sources, but exhaustiv e detail describing the location of each injury on the body. Such close examination has revealed su rprising results. For example, although it had been noted that the frequency of fresh scrapes was increasing on the turtles at the SLNPP, the location of the fresh scrapes ha d not been quantified, nor was it known that with each passing year higher frequencies of turtles within smaller size classes were being affected. Furthermore, the injury lo cation analysis indicate that it may be more advantageous for researchers to place passive integrated transponde r tags (PIT) in the neck region due to the lower number of in jury records found between the neck and flippers, thereby possibly increasing tag re tention rates and the ability to identify individual turtles in subsequent captures. This could be esp ecially important in research programs where placement of a single PIT tag (and no external tags) is standard. It is highly recommended that sea turtle researchers implement the use of the STIIS as part of their research programs. The appl ication of the STIIS particularly within longterm nest monitoring and tagging programs, as well as data from long-term open water mark recapture studies is significantly importa nt to the future success of systematic sea turtle injury identification. Collection of such data would allow valu able insight into the types, sources, and locations of injuries w ithin each species, and additionally within size classes (life stages) and sex class. This process would allow for a much deeper understanding of the impacts of each injury source. Such crucial information is currently missing from life history models, and could be limiting the ability of such models to predict accurate survival rates. Unfortunately, most models include no information

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87 regarding the non-lethal effects that natural and anthropoge nic threats have on sea turtle populations. The collection of systematic in jury data would provide the information necessary to improve population models and address various research questions. For example, do certain types of injuries resul ting from anthropogenic and natural injury sources reduce a turtle’s ability to forage properly, escape future predation, and reproduce? Injuries such as loss of eyesight , flipper amputations, and severe carapace damage could have severe effects on the re productive success of sea turtles, and thereby diminish recruitment to current populations. Re ar flipper loss in adult female turtles is one injury type that has been shown to redu ce a turtle’s ability to properly dig an egg chamber (Miller et al. 2003). Are adult male turtles reproductively impaired by flipper loss? Are juvenile tur tles more or less likely to survive to adulthood if they are missing an eye or a flipper? One of the objectives successfully addr essed in this project was to begin quantifying the number of turtles with injuries that could diminish their ability to function ecologically and biologically in the wild. The work culmin ated in the STIIS (detailed injury records) can be combined with dire ct field observations to possibly further our understanding of how certain t ypes and causes of injuries ma y be affecting the long-term survival of sea turtles. .

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88 APPENDIX A FLIPPER AMPUTATIONS MAY THROUGH DECEMBER 2000 Table A-1. All flipper amputations (less than half, half, over ha lf, and entire) within species ( Caretta caretta and Chelonia mydas ), size class, and sex class (male, female and unknown sex) May through December 2000 at the SLNPP. Straight standard carapace length (cm) # of Male# of Female# of Unknown Sex / Total Species % Missing 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 100109 Total Less than half 0-0-0 0 0-0-0 0 0-0-1 1 0-0-1 1 0-3-0 3 0-5-0 5 0-0-0 0 0-8-2 10 Half 0-0-0 0 0-0-0 0 0-0-0 0 0-0-1 1 0-1-0 1 0-0-0 0 0-0-0 0 0-1-1 2 Over half 0-0-0 0 0-0-0 0 0-0-0 0 0-0-1 1 0-0-1 1 0-3-0 3 0-0-0 0 0-3-2 5 Caretta caretta Entire 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-1-1 2 1-0-0 1 0-0-0 0 1-1-1 3 Less than half 0-0-2 2 0-0-2 2 0-0-1 1 0-0-2 2 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-7 7 Half 0-0-1 1 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-1 1 Over half 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 Chelonia mydas Entire 0-0-1 1 0-0-1 1 0-0-1 1 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-0 0 0-0-3 3 Total 0-0-4 4 0-0-3 3 0-0-2 2 0-0-2 2 0-0-1 1 0-0-3 3 0-5-2 7 1-8-0 9 0-0-0 0 1-13-17 31

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89 APPENDIX B SUMMARY OF INJURY RESULT S MAY THROUGH DECEMBER 2000 Table B-1. Summary of injury results for know n causes (barnacle, tar, fishing, social, boat propeller strike, and shark) Ma y through December 2000 at the SLNPP. Species Id Date SSCL cm Anatomical Numerical View Type Depth Recency Cause CC XXP 105 11/27 51 carapace 2cd dorsal depr ession deep fresh barnacle CC XXJ 542 06/06 74 plastron 7cd ventral depre ssion superficial healed barnacle CM XX M74 2 09/28 32 plastron 7d ventral depression deep healed barnacle CM XXJ 048 05/17 40 carapace 2c dorsal depressi on superficial healed barnacle EI XXJ 881 08/21 48 plastron 7cd ventral discol oration superficial fresh tar EI XXJ 881 08/21 48 front left flipper 3cd ventral discolorati on superficial fresh tar EI XXJ 881 08/21 48 front right flipper 4cd ventral discolorati on superficial fresh tar EI XXJ 881 08/21 48 rear left flipper 5cd ventral discolorati on superficial fresh tar EI XXJ 881 08/21 48 rear right flipper 6cd ventral discolorati on superficial fresh tar CM XXJ 451 05/24 40 front left flipper 2d dorsal puncture deep fresh fishing CC XXJ 637 06/25 87 left eye 9 . cut superficial fresh social CC XXJ 530 06/26 88 head 1 dorsal cut superficial fresh social CC XXJ 530 06/26 88 mouth 11 . bite deep fresh social CC XXJ 459 05/26 96 neck 12 dorsal bite superficial healed social CC XXJ 746 07/13 99 neck 12 dorsal bite superficial partial social CC XXJ 797 07/29 103 neck 12 dorsal bite superficial partial social CM XXJ 719 07/07 86 rear left flipper 5abcd dorsal abrasion superficial partial social CM XXJ 719 07/07 86 rear right flipper 6cd dorsal abrasion superficial partial social CM XXJ 628 06/24 97 front left flipper 3d ventral other superficial healed social CM XXJ 628 06/24 97 front right flipper 4d ventral other superficial healed social CM XXJ 565 06/12 97 front left flipper 3b dorsal abrasion superficial partial social CM XXJ 565 06/12 97 front right flipper 4b dorsal abrasion superficial partial social CM XXJ 565 06/12 97 rear left flipper 5bd dorsal abrasion superficial partial social

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90 Table B-1. Continued Species Id Date SSCL cm Anatomical Numerical View Type Depth Recency Cause CM XXJ 565 06/12 97 rear right flipper 6bd dorsal abrasion superficial partial social CM XXJ 565 06/12 97 plastron 7abcd ventral creas e superficial partial social CM XXJ 615 06/22 99 neck 12 dorsal bite superficial partial social CC XXJ 562 06/10 60 carapace 2ab dorsal slice deep healed boat CC XX D44 9 08/29 68 carapace 2abcd dorsal slice deep healed boat CC XX M76 1 10/06 70 carapace 2acd dorsal slice deep healed boat CC X1 07/16 70 carapace 2ac dorsal slice deep partial boat CC XXJ 821 08/01 76 carapace 2ab dorsal/ ventral slice deep healed boat CC XXJ 742 07/12 83 carapace 2ab dorsal/ ventral slice deep partial boat CC XXJ 567 06/12 83 carapace 2ab dorsal slice deep healed boat CM XXP 169 12/27 31 carapace 2abd dorsal s lice deep partial boat CM X5 11/08 60 carapace 2abc dor sal slice deep partial boat CC XXJ 705 07/05 67 carapace 2bd dorsal bite deep partial shark CC XXJ 705 07/05 67 plastron 7a ventral bite deep partial shark CC XXJ 734 07/10 68 plastron 7ac ventral bite superficial healed shark CC XXJ 717 07/07 69 front right flipper 4cd dorsal/ ventral bite superficial healed shark CC XXJ 717 07/07 69 carapace 2ab dorsal bite superficial healed shark CC XXJ 717 07/07 69 plastron 7abd ventral bite superficial healed shark CC XXJ 717 07/07 69 rear right flipper 6cd ventral bite superficial healed shark CC XXJ 717 07/07 69 rear left flipper 5cd ventral bite superficial healed shark CC XXJ 668 06/29 70 carapace 2bd dorsal rake mark s superficial healed shark CC XXJ 668 06/29 70 plastron 7ac ventral bite superficial healed shark CC XXJ 546 06/06 71 carapace 2bd dorsal bite deep partial shark CC XXJ 546 06/06 71 carapace 2b dorsal/ ventral missing (crescentshaped) . partial shark CC XXJ 546 06/06 71 rear right flipper 6ab (half) dorsal/ ventral amputation . partial shark CC XXJ 546 06/06 71 plastron 7ac ventral bite deep partial shark CC XX M74 4 09/28 71 carapace 2a dorsal/ ventral missing (crescentshaped) . healed shark CC XXJ 421 05/21 74 plastron 7abcd ventral bite . healed shark CC XXJ 421 05/21 74 rear left flipper 5d ventral bite . healed shark

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91 Table B-1. Continued Species Id Date SSCL cm Anatomical Numerical View Type Depth Recency Cause CC XXJ 577 06/17 78 front right flipper 4a dorsal/ ventral bite deep partial shark CC XXJ 763 07/17 88 front left flipper 3b dorsal/ ventral bite deep partial shark CC XX M76 8 10/07 89 front left flipper 3c dorsal/ ventral bite deep healed shark CC XXJ 401 05/08 95 front left flipper 3a dorsal/ ventral bite deep partial shark CC XXJ 401 05/08 95 front right flipper 4abcd dorsal/ ventral bite deep partial shark CC XXJ 401 05/08 95 plastron 7d ventral bite deep partial shark CC XXJ 457 05/26 97 front left flipper 3cd ventral bite deep healed shark CC XXJ 457 05/26 97 plastron 7b ventral bite superficial healed shark

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93 Congdon, J. D. 1989. Growth and reproduction in the blanding's turtle: a life history model for sea turtles. Pages 31-32 in K. L. Eckert, S. A. Eckert, and J. I. Richardson, editors. Proceedings of th e 9th annual symposium on sea turtle biology and conservation. NOAA Technical Memorandum. Davenport, J., and W. Clough. 1985. The use of limbscales or "pseudoclaws" in food handling by young loggerhead turtles. Copeia 3 :786-788. Dennis, B., P. L. Munholland, and J. M. Sco tt. 1991. Estimation of growth and extinction parameters for endangered sp ecies. Ecological Monographs 61 :115-144. Doak, D., P. Kareiva, and B. Klepetka. 1994. Modeling population viability for the desert tortoise in the western Mojave Desert. Ecologica l Applications 4 :446-460. Dodd, C. K. 1988. Synopsis of the biologica l data on the loggerhead sea turtle Caretta caretta (Linnaeus 1758). USFWS Biologi cal Report 88(14). Ecological Associates Inc. 2000. Physical and ecological factors infl uencing sea turtle entrainment levels at the St. Lucie Nuclear Power Plant 1976-1998. Submitted to FPL. Ernst, C. H., R. W. Barbour, and J. E. L ovich. 1994. Turtles of the United States and Canada. Smithsonian Institution Press, Washington, D.C. Fergusson, I. K., L. J. V. Compagno, and M. A. Marks. 2000. Predation by white sharks Carcharodon carcharias (Chondrichthyes: Lamnidae) upon chelonians, with new records from the Mediterranean Sea and a first record of the ocean sunfish Mola mola (Osteichthyes: Molidae) as stomach contents. Environmental Biology of Fishes 58 :447-453. Frick, M.G., K.L. Williams, and M. Robins on. 1998. Epibionts associated with nesting loggerhead sea turtles ( Caretta caretta ) in Georgia, U.S.A. Herpetological Review 29:211-214. George, R.H. 1997. Health problems and diseases of sea turtles. In P.L. Lutz and J.A. Musick (eds.). The biology of sea tur tles, 363-385. Boca Raton, FL: CRC Press. Gulko, D., and K. L. Eckert. 2003. Sea turtles: an ecological guide. Mutual Publishing, Honolulu, HI. Heithaus, M.R. 2001a. Shark attacks on bottlenose dolphins ( Tursiops aduncus ) in Shark Bay, Western Australia; attack rate, bite scar frequencie s, and attack seasonality. Marine Mammal Science 17 :526-539.

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94 Heithaus, M. R. 2001b. The biology of tiger sharks, Galeocerdo cuvier, in Shark Bay, Western Australia: sex ratio, size distribution, diet, and se asonal changes in catch rates. Environmental Biology of Fishes 61 :25-36. Heithaus, M. R., A. Frid, and L. M. Dill. 2002. Shark-inflicted injury frequencies, escape ability, and habitat use of green a nd loggerhead turtles. Marine Biology 140 :229236. Hilburn, H. O., J. I. Richardson, J. McVea, and J. M. Watson. 1995. Worldwide incidental capture of sea turtles. Pages 489-495 in K. A. Bjorndal, editor. Biology and Conservation of Sea Turtles, revised edition. Smithsonian Institution Press, Washington, D.C. Hirth, H. F. 1980. Some aspects of the nesti ng behavior and reproduc tive biology of sea turtles. American Zoologist 20 :507-523. Jorgenson, J. T., M. Festa-Bianchet, J. Ga illard, and D. Wishart. 1997. Effects of age, sex, disease, and density on surv ival of bighorn sheep. Ecology 78 :1019-1032. Kamezaki, N. 2003. What is a l oggerhead turtle? Pages 28-43 in A. B. Bolten and B. E. Witherington, editors. Loggerhead Sea Turtles. Smithsonian Institution, Washington, D.C. Lenhardt, M. L., S. Bellmund, R. A. Byles, S. W. Harkins, and J.A. Muskick. 1983. Marine turtle reception of bone-conducted sound. J. Aud. Res. 23 (2):119-126. Limpus, C.J., P.J. Couper, and M.A. Read. 1994. The loggerhead turtle Caretta caretta , in Queensland: population structure in a warm temperate feeding area. Memoirs of the Queensland Museum 37 :195-204. Limpus, C. J., and D. J. Limpus. 2003. Biology of the loggerhead turtle in Western South Pacific Ocean foraging areas. Pages 93-113 in A. B. Bolten and B. E. Witherington, editors. Loggerhead Sea Turtles. Smithsonian Institution, Washington, D.C. Loughin, T. M., and P. N. Scherer. 1998. Tes ting for association in contingency tables with multiple column responses. Biometrics 54 :630-637. Marquez, M. R. 1990. Sea turtles of the worl d. An annotated and illustrated catalogue of sea turtle species known to date. FAO Fish Synopsis 125 :1-81. McCauley, S. J., and K. A. Bjorndal. 1999. C onservation implications of dietary dilution from debris ingestion: sublethal effects in post-hatchling logg erhead sea turtles. Conservation Biology 13 :925-929.

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95 Meylan, A. B., and P. A. Meylan. 1999. In troduction to the evolu tion, life history, and biology of sea turtles. Pages 3-5 in K. L. Eckert, K. A. Bjorndal, F. A. AbreuGrobois, and M. Donnelly, editors. Resear ch and Management Techniques for the Conservation of Sea Turtles. IUCN/SSC Marine Turtle Specialist Group No. 4, Washington, D.C. Miller, J. D., C. J. Limpus, and M. H. Godfrey. 2003. Nest site selection, oviposition, eggs, development, hatchling, and emer gence of loggerhead turtles. Pages 125143 in A. B. Bolten and B. E. Witherington, editors. Loggerhead Sea Turtles, Washington, D.C. Milton, S., P. L. Lutz, G. Shigenaka, R. Z. Hoff, R. A. Yender, and A. J. Mearns. 2003. Oil and sea turtles: biology, planning , and response. National Oceanic and Atmospheric Administration. Moein, B. S., J. A. Musick, and M. L. Lenha rdt. 1999. Auditory evoked potentials of the loggerhead sea turtle ( Caretta caretta ). Copeia 1999 (3):836-840. Murphy, S. R., D. W. Owens, and T. M. Murphy. 2003. Ecology of immature loggerheads on foraging grounds and adults in internesting habitat in the eastern United States. Pages 79-92 in A. B. Bolten and B. E. Witherington, editors. Loggerhead Sea Turtles. Smithsonian Institution, Washington, D.C. Murtaugh, P. A. 1981. Inferring properties of mysid predation from injuries to Daphnia . Limnology Oceanography. 26 :811-921. Nakaoka, M. 2000. Nonlethal effects of predat ors on prey populations: predator-mediated change in bivalve growth. Ecology 81 (4):1031-1045. Oravetz, C. A. 1999. Reducing incidental catch in fisheries. Pages 189-193 in K. L. Eckert, K. A. Bjorndal, F. A. Abreu-Gr obois, and M. Donnelly, editors. Research and Management Techniques for the Cons ervation of Sea Turtles. IUCN/SSC Marine Turtle Specialist Group, Washington, D.C. Preen, A. R. 1996. Infaunal mining: a novel foraging method of loggerhead turtles. Journal of Herpetology 30 :94-96. Quantum Resources Inc. 2004. Florida Powe r & Light Co. St. Lucie Unit 2 annual environmental operating report 2003. Prepar ed by Quantum Resources Inc., for Florida Power & Light Company, Juno Beach, FL. Quantum Resources Inc. 2005. Florida Powe r & Light Co. St. Lucie Unit 2 annual environmental operating report 2004. Prepar ed by Quantum Resources Inc., for Florida Power & Light Company, Juno Beach, FL.

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96 Ridgway, S.M., E. G. Wever, and J. G. Mc Cormick. 1969. Hearing in the giant sea turtle, Chelonia mydas . Proc. of the National Academy of Sciences 64 (3):884-890. Schoener, T. W. 1979. Inferring the properties of predation and other injury-producing agents from injury frequencies. Ecology 60 :1110-1115. Shimada, K., and G. E. Hooks III. 2004. Shar k-bitten protostegid turtles from the upper cretaceous Mooreville Chal k, Alabama. J. Paleontology 78 :205-210. Simpfendorfer, C. A., A. B. Goodreid, and R. B. McAuley. 2001. Size, sex and geographic variation in the diet of the tiger shark, Galeocerdo cuvier , from Western Australian waters. Expe rimental Biology of Fishes 61 :37-46. Smith, G.M. and C.W. Coates. 1938. Fibroepithel ial growths of the skin in large marine turtles Chelonia mydas (L.). Zoologica 23 :93-98. Stancyk, S. E. 1982. Non-human predators of sea turtles and their control. Pages 139-152 in K. A. Bjorndal, editor. Biology and C onservation of Sea Turtles. Smithsonian Institution, Washington, D.C. Walsh, M. 1999. Rehabilitation of sea turtles. Pages 202-207 in K. L. Eckert, K. A. Bjorndal, F. A. Abreu-Grobois, and M. Donnelly, editors. Research and Management Techniques for the Conservati on of Sea Turtles. IUCN/SSC Marine Turtle Specialist Group No. 4, Washington, D.C. Werner, P. A., and H. Caswell. 1977. Popul ation growth rates and age versus stagedistribution models for teasel (Dipsacus sylvestris Huds.). Ecology 58 :1103-1111. Witherington, B. E. 1994. Flotsam, jetsam, post-hatchling loggerhead s, and the advecting surface smorgasbord. Pages 166-167 in K. A. Bjorndal, A. B. Bolten, D. A. Johnson, and P. J. Eliazar, editors. Proceedings of the Fourteenth Annual Symposium on Sea Turtle Biology an d Conservation, Hilton Head, South Carolina. Witherington, B. E. 2003. Biological cons ervation of Loggerheads: challenges and opportunities. Pages 295-311 in A. B. Bolten and B. E. Witherington, editors. Loggerhead Sea Turtles. Smithsonian, Washington, D.C. Witzell, W. N. 1983. Synopsis of biol ogical data on the hawksbill turtle, Eretmochelys imbricata (Linnaeus, 1766). FAO Fish Synopsis 137 :78. Witzell, W. N. 1987. Selective predation on la rge cheloniid sea turtles by tiger sharks ( Galeocerdo cuvier ). Japanese Journal of Herpetology 12 :22-29.

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97 Witzell, W. N., A. L. Bass, M. Bresette, D. A. Singewald, and J. Gorham. 2002. Origin of immature loggerhead sea turtles ( Caretta caretta ) at Hutchinson Island, Florida: evidence from mtDNA markers. Fisheries Bulletin 100 :624-631. Young, R. 1992. Tiger shark consumes young s ea turtle. Marine Turtle Newsletter 59 :14. Zug, G. R., G. Balazs, J. A. Wetherall, D. M. Parker, and S. K. K. Murakawa. 2001. Age and growth of Hawaiian green seaturtles ( Chelonia mydas ): an analysis based on skeletochronology. Fisheries Bulletin 100 :117-127.

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98 BIOGRAPHICAL SKETCH April Diane Norem was born in Plym outh, Indiana, on September 13, 1977. She graduated from Plymouth High School in 1996 a nd graduated with a Bachelor of Science in May 2000 from Purdue Univer sity, West Lafayette, Indiana. Before starting her Master of Science in Interdisciplinary Ecology at the University of Flor ida in August 2003, April worked as a seasonal animal keeper for the In dianapolis Zoological Society, a veterinary technician in San Diego Calif ornia, an intern at Moss Landing Marine Laboratory in central California, a wildlife kayak guide in Monterey Bay National Marine Sanctuary, and as a sea turtle technician in both Georgia and Florida.