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Title: USVI Caribbean spiny lobster assessment
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Title: USVI Caribbean spiny lobster assessment
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    Figures and tables
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Full Text


SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003



Final Report





to the
U.S. Fish and Wildlife Service


Southeast Area Monitoring and Assessment Program
U.S. Virgin Islands


State


:United States Virgin Islands


Project Number :NAO7FS0100


Project Title :Caribbean/NMFS Cooperative SEAMAP Program


Study Title :USVI Caribbean Spiny Lobster Assessment


Period Covered :April 2002 to June 2003

Report Written By :Shenell Gordon & Jason Vasques
Division of Fish and Wildlife, Department of Planning and
Natural Resources, U.S. Virgin Islands

Project Staff :Stacy Albritton, Ruth Gomez, Julian Aubain and Dr. K.
Roger Uwate

Date Of Report :February 2004

Report Reviewed By :K. Roger Uwate, Ph.D. Chief of Fisheries, DFW-DPNR
Barbara Kojis, Ph.D. Director of Fish & Wildlife, DFW-DPNR






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 2
Period: April 2002 June 2003


INTRODUCTION

Spiny lobsters (Palinuridae) are among the most economically important crustaceans in the world
(Olsen et al. 1975). Spiny lobster catches in the greater Caribbean region accounted for 17% of the
world's lobster production from 1978-1991, and is the species of highest commercial value in
countries such as Cuba, Brazil, Bahamas, and Florida (CARICOM 1996). Florida, for example,
commercially harvested approximately 2,721,088 kg annually over the last 20 years, and 907,029 kg
annually in recreational landings (Bertelsen and Matthews 2001). The Caribbean Spiny lobster,
Panulirus argus, also supports an important commercial and recreational fishery in the U.S. Virgin
Islands (USVI).

Understanding adult populations of P. argus includes studying trends in settlement and recruitment.
A degree of variance in recruitment is characteristic of most invertebrate fisheries. Thus, settlement
and early post-settlement processes that influence recruitment demand great attention (Butler and
Herrnkind 1997). Witham collectors give a measure of the relative abundance of pueruli in an area
and have been used to make general comparisons across areas (Witham et al. 1968). Similar devices
have been used in Australia to correlate postlarvae abundance with commercial catches several years
later (Cruz et al. 1995). Butler and Herrnkind (1997) used this relationship to predict maximum
sustainable yield of the western rock lobster, Panulirus cygnus. Long term monitoring can detect
trends and changes in populations over time, thereby revealing information about spiny lobster
stocks and sustainability of harvests. Nevertheless, it is not enough to only study trends in settlement
and recruitment, juvenile habitat requirements must also be identified.

Over the last decade Witham collectors have been used in the US Virgin Islands for repeated
sampling at selected sites to explore temporal trends in P. argus pueruli settlement and abundance
(for 1992-93 see Quinn and Kojis 1997; and for 1997-98 see Kojis et al. 2003). These studies were
done around St. Thomas both inside and outside the Cas Cay/Mangrove Lagoon and Great St. James
Marine Reserves.

Juvenile and adult P. argus use a variety of benthic marine habitats (Herrnkind and Butler 1986;
Butler et al. 1997; Herrnkind et al. 1997; and Acosta and Butler 1997). However, the affect of
habitat characteristics on juvenile dispersal is unclear. The availability of refuge structures are
thought to strongly influence survival, distribution and abundance of small benthic crustaceans
(Caddy 1986). Crevices and other interstices for evading predators are especially important to
vulnerable early benthic stages of spiny lobster (Herrnkind and Butler 1986). Specifically,
insufficient sheltering structure is thought to limit early recruitment in some areas (Wahle and
Steneck 1991).

According to Andree (1981), postalgal phase juveniles move out of vegetated areas and seek refuge
crevices when they reach 15-20 mm CL. Soca-Cordero et al. (1998) reported that artificial shelters
placed in benthic habitats deprived of hardbottom (natural shelter) enhanced juvenile populations.
According to Bolden (2001) and Mateo and Tobias (2001), the USVI lobster fishery may be in
decline. Therefore, besides surveying pueruli lobster in this study, an effort was made to investigate
artificial shelters for juvenile P. argus in areas devoid of appropriate juvenile habitat.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 3
Period: April 2002 June 2003


Study Objectives

The main objectives of this study were: (1) to examine spatial and temporal variations in P. argus
pueruli settlement and relative abundance within marine reserve habitats located on the east end of
St. Thomas, USVI; (2) compare trends in relative abundance and settlement of pueruli between
1992-93, 1997-98, and 2002-03; and (3) to evaluate the use of artificial habitat enhancement
structures on juvenile lobster occupancy or abundance.


MATERIALS, METHODS, AND STUDY SITES

Pueruli Settlement and Abundance

1. Modified Witham Collectors

Pueruli collectors (see Figure 1) were modified from the original design used by Witham et al.
(1968). Collector frames were made from 1.90 cm diameter closed PVC pipes that measured 40.5
cm x 40.5 cm, and were comprised of four crossbars connected by 90 elbows. For each collector,
four "hogs hair" air-conditioning filters were cut into 40.5 cm x 61 cm pieces. They were then
folded lengthwise with the webbed backing material to the inside, slipped over each crossbar on the
PVC ladder frame, and secured with plastic tie-straps. Each collector was anchored by '2 inch
diameter polypropylene rope to two concrete building blocks (40 x 20 x 15 cm each). Block sets
were bounded together with rubber hose collars around /2 inch polypropylene rope. A sub-surface
buoy was used to suspend each collector at each site.


2. Study Sites and Collector Deployment

Using a WAAS GPS study sites (Figure 2 and Appendix 1) were located from previous studies by
Quinn and Kojis (1997) and Kojis et al. (2003). In 1997-98 sampled sites included Mangrove
Lagoon, Cas Cay, Nazareth Bay, northwest Great St. James and southwest Great St. James (Kojis et
al. 2003). In 1992-93 however, Quinn and Kojis (1997) only sampled the Mangrove Lagoon and
southwest Great St. James Island sites.

On 4 June 2002, two pueruli collectors each were deployed at five selected sites within the Cas
Cay/Mangrove Lagoon and Great St. James Marine Reserves on the southeast side of St. Thomas
(Figure 2). A subsurface buoy was used to suspend each collector at each site. If vessel traffic at a
site was low, then a surface buoy was used to facilitate locating the site.

The Mangrove Lagoon site (180 18.333'N, 64 52.474'W) was located in a protected shallow
channel in the Inner Mangrove Lagoon Marine Reserve (see Figure 2). The inner lagoon is enclosed
and experiences limited flushing and water currents. This site is a mangrove habitat with a dense
algal plain over fine sand and mud. The dominant vegetation was low canopy macroalgae consisting
ofHalimeda spp., Penicillus spp., Udotea spp., and cyanobacteria. The Witham collectors at this
site were anchored approximately Im below the surface in water about 2.0 m deep and placed about






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 4
Period: April 2002 June 2003

8 to 10 m apart from each other.

The Cas Cay site (180 18.548'N, 64 52.118'W) was located in the Cas Cay/ Mangrove Lagoon
Marine Reserve (see Figure 2). Collectors were set just below the surface in water approximately
1.5 m deep, and placed within a halo of sand surrounded by a dense seagrass bed of Thallasia
testudium and Syrigodiumfiliformi. This site was adjacent to the north shoreline of Cas Cay. These
collectors were placed about 10 m apart and were exposed to constant trade winds from the south
and southeast, as well as associated wave action.

The collectors at Nazareth Bay (180 19.069'N, 64 51.416'W) were located in the St. James Marine
Reserve and were positioned over a sparse homogeneous seagrass bed (Syrigodiumfiliformi),
approximately 100 m from the rocky shoreline of St. Thomas (see Figure 2). The Nazareth Bay
collectors were suspended 3 m below the sea surface in approximately 6 m of water. Collectors
were 10 m apart.

The northwest side of Great St. James (1818.794'N, 6449.075'W), located in the St. James Marine
Reserve, was patchy coral reef/sand habitat (see Figure 2). This site was adjacent to (-20 m away
from) the rocky shoreline and Current Cut Passage, which experiences moderate to strong tidal
currents. The collectors at this site were set 3 m below the surface in water that was approximately 8
m deep. The collectors here were placed 10 m apart.

The last site, southwest Great St. James (1818.403'N, 64 50.140'W), also located in the St. James
Marine Reserve, was a patchy mixed algal and seagrass/sand habitat (see Figure 2). Heavy water
movement and current occurred along this side of the bay. Collectors at this site were set 3 m below
the surface and were deployed in approximately 11 m of water. The collectors were set about 15 m
apart.


3. Sampling

Collectors were sampled every two weeks over a 12 month period (from June 18, 2002 to June 17,
2003). The collectors were sampled by snorkellers at all sites. Prior to bringing a collector to the
surface, it was enclosed in a 1 square meter mesh bag with 1 mm square mesh. Once covered by the
bag, the collector was then unclipped and the bag and collector were brought on board a boat for
inspection. All lobster pueruli and juveniles were counted and returned unharmed at each site.
Pueruli were staged as follows: transparent, semi-pigmented, pigmented, and algal-phase juvenile
(see Bannerot et al. 1992; CARICOM 1996; and Butler and Herrnkind 1997; see also Appendix 2
for definitions). Damaged, lost, or heavily encrusted collectors were replaced immediately after
inspection. Each sample period represented a 14 to 16 day settlement period.


4. Data Analysis

Paried T-tests were used initially to test for differences between collectors at each site. No
difference was detected in pueruli abundance between collectors within a site (P>0.05) in all cases
except Cas Cay. Collectors at Cas Cay often broke and were lost, therefore, the samples were






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 5
Period: April 2002 June 2003

unbalanced and classical t-tests could not be used. For this reason, the data at Cas Cay was log(x+l)
transformed and an one way ANOVA was conducted to test for differences between the Cas Cay
collectors. The results of the one way ANOVA on the transformed data was marginal (F1, 52=3.826,
P=0.056) between collectors. Therefore, it was decided that rather than disregard the Cas Cay site,
CPUE should be used to make comparisons between sites, since the formula used for CPUE
accommodates missing samples and a disproportionate number of days between sample periods.
Catch per unit effort (CPUE) was calculated by dividing the total catch for each site by the number
of days between sample periods then dividing this by the number of collectors at that site (usually 2).
Thus, unless otherwise specified, CPUE = (total catch/ number of days between sample
periods)/number of collectors. CPUE calculations included first stage juveniles (dark pigmented
body; -5-15 mm CL) as well as pueruli. Samples that had missing or detached collectors were not
included in the data analysis (Cas Cay site for example). Standard one-way ANOVA was then used
to test for differences in catch per unit effort between sample sites.

Timing in settlement was examined graphically, and by month and site. Lunar phase (new moon,
first quarter, full moon, last quarter) was defined for each sample date. Sample dates without a
distinct/obvious lunar phase were assigned to the nearest lunar phase.

Comparison between years was by graphical comparison of CPUE and by using ANOVA to test for
differences between years. Catch per unit effort data from previous project studies (Quinn and Kojis
1997 and Kojis et al. 2003) were standardized for direct comparison to 2002-2003 data. The
northwest St. James and southwest St. James sites in 2002-2003 were combined to allow comparison
to the 1992-1993 and 1997-1998 data sets.


Juvenile Lobster Artificial Shelters

1. Artificial Shelter Construction

In an effort to study the status of the lobster fishery and the efficiency of artificial shelters,
CARICOM (1996) recommended that a standard shelter be deployed at 20 m and monitored on a
regional level. Therefore, ten sets of lobster shelters were constructed after the model suggested by
the CARICOM (1996). Each shelter consisted of 16 large concrete cement blocks (40 x 20 x 15 cm
each) with three square holes per block. The 16 blocks were arranged in a two-level quadrangular
structure with an open central area (see Figure 3).


2. Artificial Shelters Study Site and Installation

The study area selected for shelter installation was located east southeast of Cow and Calf Rocks and
south of Great St. James (start of shelters: 180 17.986'N, 64 50.230'W; end of shelters: 180
17.998'N, 640 50.375'W; see Figure 2 and Appendix 3). It was an area approximately 20 m deep
with a relatively flat sandy bottom and sparse algae plain. The prominent algae were Halimeda spp.,
Penicillus spp., Udotea spp., and Caulerpa spp., along with sparsely scattered sessile invertebrates.

On 11 June 2002, ten sets of block shelters were deployed. Each set of shelter blocks were first






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 6
Period: April 2002 June 2003

lowered from a surface vessel and spaced approximately 30 m apart. These were later arranged
underwater by divers. Each of the ten shelters was marked by a guide rope 1-2 m away from the
juvenile shelters for divers to follow. Sub-surface marker buoys were deployed at each end of the
artificial shelter sites. Because only one juvenile lobster was encountered from July to October
2002, at the October 2002 Southeastern Area Monitoring and Assessment Program Caribbean
(SEAMAP-C) meeting; it was decided that half of the artificial shelters should be covered.
Therefore, on 19 December 2003 five of the ten shelters were covered with aluminum sheets (about
75 x 75 cm) and secured with large cable ties. Every other shelter was covered.


3. Sampling and Data Analysis

Shelter occupancy by juvenile lobsters was checked every three months (quarterly) over a 12 month
period from June 2002 to June 2003. The shelters were sampled by underwater visual observation
using SCUBA gear. Two divers inspected each shelter and counted the number of juvenile lobsters
observed in each. Estimates were made on the total carapace length (CL) of each lobster present.
Shelters that either collapsed or became buried in sand were re-adjusted so that the block holes were
clear of debris.

Because of the paucity of lobsters colonizing the shelters (total of 2 juvenile lobsters), analysis was
limited.


RESULTS

Modified Witham Collectors

Five sites, with two Witham collectors each, were sampled from 18 June 2002 to 17 June 2003. A
total of 202 postlarvae were observed (Table 1). During a single sampling period, a maximum of 40
pueruli settled across all collectors. Of the total catch, ten (5%) of the pueruli collected were
transparent, 19 (9%) were semi-pigmented, 28 (14%) were pigmented, and 145 (72%) were early
algal-phase juveniles (Table 1; Appendix 4).


Spatial Variation

The abundance of pueruli at most sites was consistently low (Table 1, Figure 4). However, overall
pureuli abundance in Nazareth Bay (total = 127) was considerably higher than the other four sites
(Table 1, Figure 4). The overall catch between the Mangrove Lagoon and Cas Cay sites were
similar with 19 and 18 pueruli respectively. Northwest Great St. James exhibited the lowest total
catch with 10 postlarvae while southwest Great St. James had a total abundance of 28 (Table 1,
Figure 4).

Catch per unit effort (CPUE) varied across sites (One way ANOVA: F4, 127 =4.355, P=0.002, see
Appendix 6 and compare Figures 5 to 9 and Appendix 5). Nazareth Bay consistently yielded a
higher CPUE in 2002-2003 than the other four sites (compare Figures 5 to 9). Pairwise comparisons






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 7
Period: April 2002 June 2003

(Tukey's test) indicated CPUE at Nazareth Bay was greater than the other sites in all cases
(Appendix 6), but that no differences existed between the remaining four sites.


Temporal Variation

Peaks in pueruli settlement occurred primarily in the spring and early summer (Figure 10). The
collectors at the Mangrove Lagoon, Cas Cay, and northwest Great St. James had low settlement rates
not exceeding 0.15 pueruli/day/collector (CPUE) on any particular sample date (Figures 5, 6 and 8;
Appendix 5). Seasonal peaks for the Cas Cay and the two Great St. James sites were the spring and
summer months (Figures 6, 8, and 9). The two collectors at southwest Great St. James had high
settlement rates during the summer months, which decreased and stayed below a CPUE of 0.08
pueruli/day/collector during most of the remaining sample year (Figure 8; Appendix 5). The greatest
settlement rate occurred in May 2003 at the Nazareth Bay site, with a peak CPUE of 1.54
pueruli/day/collector over a single sample period (Figure 7; Appendix 5). This is mainly due to the
large number of pueruli (40 pueruli) that were observed in the 6 May 2003 sample.

In 2002-2003, pueruli abundance on Witham collectors was greatest across all sites during first
quarter moon phases (Table 2). The total number of pueruli collected during the first quarter phase
accounted for 73% of all settlement. CPUE was combined for all sites and plotted as a function of
the number of days the sample was taken after the new moon. The highest and most prevalent
CPUE values occurred between the new moon and first quarter phases (Figure 11).

CPUE was generally greater in 1992-1993 than in either 1997-1998 or 2002-2003 (Table 3; Figures
12-15). Two way ANOVA indicated that there were differences in CPUE between years (F2,280
=10.88, P<0.001) and across sites for the combined years (F3, 280= 8.798, P<0.001) (see Appendix 7).
However, because only two sites were sampled in 1992-1993, there was no test for interactions as
some treatments were missing. CPUE has steadily declined from 1992 to the present at both the
Mangrove Lagoon site and the St. James site (see Appendix 7-Tukey test; Figure 16). From 1997-
1998 to 2002-2003, CPUE declined at all sites except the St. James sites where the mean annual
CPUE increased slightly from 0.02 to 0.03 pueruli/day/collector (Table 3; Figure 16).


Artificial shelters occupancy by juvenile lobsters

A total of 2 juvenile lobsters were observed during this one year study (Table 4). Only 1 juvenile
lobster was found in the uncovered shelters and 1 was found in the covered shelters. The small
number of lobsters in this study precluded a statistical analysis of lobster abundance among shelters.


DISCUSSION

Many variables contribute to the temporal and spatial variability in recruitment of P. argus.
Settlement and recruitment studies are complicated by the lengthy planktonic larval stage lasting
from a few months to one year (Lewis et al. 1952). For example, low CPUE values at the Mangrove
Lagoon site in 2002-2003 may be reflective of water quality issues (as discussed in Quinn and Kojis






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 8
Period: April 2002 June 2003

1997; and Kojis et al. 2003) and/or lack of suitable juvenile habitat. Acosta and Butler (1997)
suggested that although mangrove habitats may be important nursery habitats, the use of such was
dependant on sheltering characteristics. Kojis et al. (2003) suggested that high CPUE values in the
mangrove lagoon in 1997-98 may have been a function of the site's proximity to pueruli settlement
habitat. However in 1999, Hurricane Lenny disrupted the natural tidal flow at this site by piling
coral rubble at the lagoon/seaward interface. The resultant berm limited water flow in this area and
may have resulted in a reduction of suitable juvenile habitat as well as a reduction of larval supply to
the site. A Poritesporites bed used to lie near the collectors at the Mangrove Lagoon site.
However, Hurricane Lenny devastated the P. porites bed (personal communication, Division of Fish
and Wildlife) and reduced water flow limited P. porites growth. The P. porites bed, which at one
time could have provided adequate juvenile habitat, has since been covered with sediment and algae.
Post-algal spiny lobsters prefer silt-free environments with adequate amounts of stony corals, but
make use of mangrove prop roots whenever coral cover is sparse (Acosta and Butler 1997). The
decrease in CPUE in the mangrove lagoon before and after Hurricane Lenny, suggests that although
mangrove habitats may be important nursery areas, as implied by Little (1977), the absence of coral
may have a greater influence on postlarval settlement than merely the presence of mangroves.

The above is also supported by the fact that Nazareth Bay consistently demonstrated high settlement
rates (see Appendix 5) despite the absence of mangroves. As discussed in Kojis et al. (2003), the
high CPUE at Nazareth Bay is likely a function of pueruli supply to this site by currents.
Conversely, lower CPUE values at the St. James sites may be due to their orientation to the mass
water flow, these sites appear to be oriented in the lee of an easterly current. The northwest St.
James site is situated near an area that experiences heavy tidal currents. However, the collectors'
orientation to the current is such that the currents may flush pueruli past the collectors.

It has been suggested that the larval phase of lobster is 6 to 12 months (Lewis et al. 1952).
Therefore, it is likely that pueruli settlement in the Virgin Islands is dependant on an upstream
supply. Pueruli settling and recruiting in Florida are likewise believed to be transported north from
the Caribbean basin by the Caribbean current (Lyons 1980). However, regional patterns in
postlarval supply are highly variable and do not necessarily reflect spawning cycles (Acosta et al.
1997). The period of greatest settlement in this study was in the spring/summer (April- June).
These findings are consistent with Quinn and Kojis (1997) in which they reported highest settlement
during the summer months (April- October). Peak settlement in south Florida was from spring to
early summer (April-July, Acosta et al. 1997).

Quinn and Kojis (1997) report higher CPUE on new moons than full moons. The findings from this
study are similar. In this study, lunar cycles were broken into four lunar phases rather than two. The
results of this study indicate that higher CPUE values occurred during new moon first quarter
phases. In the Florida Keys peak settlement, based on collection of P. argus, was highly correlated
to new moon and first quarter lunar phases (Acosta et al. 1997). Pueruli typically travel and arrive at
near-shore settlement areas during new moon and first quarter lunar phases to avoid predation
(Heatwole et al. 1992). Thus, settlement may be triggered by the dark periods of a new moon and
carry through the first quarter phase resulting in high catches of pueruli during the early first quarter
phase.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 9
Period: April 2002 June 2003

In general, pueruli settlement has steadily declined from 1992-1993 through 2002-2003 (Figure
16). The CPUE of lobster pueruli observed at common survey sites in 1992-93 (Quinn and Kojis
1997), 1997-98 (Kojis et al. 2003), and 2002-03 (this study) are compared in Table 3 and Figure 16.

At Mangrove Lagoon, the overall CPUE of lobster pueruli decreased from 0.23 pueruli/day/
collector in 1992-93 to 0.09 pueruli/day/collector in 1997-98. Pueruli settlement further declined to
a CPUE of 0.03 pueruli/day/collector in 2002-03. In 1997-98, CPUE at Cas Cay was 7 times greater
(0.21 pueruli/day/collector) compared to a CPUE of 0.03 pueruli/day/collector in 2002-03. In recent
years, the Mangrove/Cas Cay Marine reserve has been subjected to non-point and point source
pollution that may affect the water quality and potential pueruli settlement in this area. Settlement
rates at Great St. James Island were lower in 1997-98 (CPUE = 0.02 pueruli/ day/collector) than
1992-93 (CPUE = 0.16 pueruli/day/collector), and remained relatively low with a CPUE of 0.03
pueruli/day/collector in 2002-03. Nazareth Bay not only had the highest CPUE (0.17
pueruli/day/collector) of all the sites in 2002-03, but maintained a relatively high settlement rate
compared to that of in 1997-98 (CPUE = 0.30 pueruli/day/collector). There are no clear reasons for
the decline in pueruli settlement over the years. Because spiny lobster have such a lengthy larval
phase (Lewis et al. 1952; and Kittaka 1994) pueruli supply is not likely to be related to adult
mortality or catch in the U.S. Virgin Islands. It is possible, however, that natural variability and the
low resolution bi-weekly sampling used in this study may have overshadowed some trends in pueruli
abundance and settlement.


Artificial Shelters

Throughout the one year study period, only 2 juveniles were encountered in the artificial shelters
(one in the covered shelters, one in the uncovered shelters, see Table 4). Five shelters were covered
on 19 December 2003 because only 1 juvenile was observed prior. Lozaro-Alvarez et al. (1994)
suggested that covers are an important feature on this type of artificial shelter. In addition to
multiple den openings, Spanier and Zimmer-Faust (1988) reported that the presence of shaded cover
was important for den choice by Panulirus interruptus. After placing lids, one additional juvenile
was seen. These results are similar to an experimental shelter study near the Cow and Calf Rocks
where no lobsters were observed from 1992 to 1994 (Quinn and Kojis 1995). Although few lobsters
were encountered in the current study, both covered and uncovered block shelters were densely
occupied by other marine organisms. Invertebrates encountered included cleaner shrimp, arrow and
hermit crabs, brittle stars, conch, triton, and large amounts of hydroids. Some of the more common
fishes observed included squirrelfish (Holocentredae), and grunts (Haemulidae). Juveniles or
commercially important fishes such as coneys (Cephalopholisfulvus), grasbys (Cephalopholis
cruentatus), Nassau groupers (Epinephelus itajara), and red grouper (Epinephelus morio) were also
observed on or near these attractors.

There are a few possible explanations for the limited occupancy of juvenile lobsters at the artificial
shelter site. The most obvious reason may be a limited larval supply. The artificial shelters were
placed (Figure 2) such that the predominant current flowed across them into Nazareth Bay and the
Mangrove Lagoon (as discussed earlier, also see Kojis et al. 2003). Because of this funneling effect,
pueruli settlement likely occurred a considerable distance away, thereby limiting the supply of
juvenile lobster to occupy the shelters. The nearest feature to attract settling pueruli was Cow and






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 10
Period: April 2002 June 2003

Calf Rocks, again a considerable distance across a predominantly sand and sparse seagrass/algal
plain. Cow and Calf Rocks may act as an oasis and hold juveniles until they are of a much larger
size to safely venture to further reefs with a greater prey base.

In addition to postlarval supply, juvenile lobster and postlarvae may actively select natural habitats
over the artificial shelters. Although Herrnkind and Butler (1986) suggest early benthic lobsters
prefer to reside in substratum with seagrass and rhodophyte algae, the habitat surrounding the
artificial shelters was predominately a sand flat. Conversely, both Cow and Calf Rocks and Great
St. James provide rocky outcroppings with moderate coral, gorgonian, and sponge growth. The
natural reefs would provide a greater food base and prey availability. Despite the complexity of the
artificial shelters, the concrete blocks were narrowly colonized by sessile organisms and probably
provided limited foraging habitat.

It is important to consider that although block shelters can potentially be attractive for juvenile
lobsters, they only adequately function in area where lobsters gather naturally (Lozano-Alvarez et al.
1994). This suggests that more importantly than physical characteristics of the shelters, local habitat
features and shelter proximity to such can determine the success of artificial shelters in attracting and
concentrating lobsters.


Future suggestions and management strategies for pueruli study

Coordinated regional sampling, such as in the British Virgin Islands and Puerto Rico, is important in
detecting correlations among lobster pueruli distribution and large scale settlement and recruitment
variations. It is critical to study the relationship between lobster settlement and recruitment to
understand and manage adult lobster stocks. Perhaps developing and conducting recruitment studies
in and around pueruli collection sites, especially at Nazareth Bay, can help clarify the transition
between settlement and recruitment. It is also important to investigate the role habitat has on newly
recruited juvenile lobsters (particularly exploring mangrove and coral reef habitats).

As more Caribbean islands participate in data collection, a better understanding of local and regional
spiny lobster dynamics should develop. This could be the basis for implementing a regional lobster
fishery management program. The USVI Government and the Caribbean Fisheries Management
Council (CFMC) use regulations that restrict harvest of undersize and berried lobsters. However,
management is limited without substantial data on habitat preference and selection, hydrological
factors affecting such selection, and extent of harvesting in the territory.


ACKNOWLEDGEMENTS

This research was funded by the NOAA-Fisheries SEAMAP program. Assistance with fieldwork
was provided by the Division of Fish & Wildlife staff Involved staff members include Stacy
Albritton, Ruth Gomez, Julian Aubain, Dr. Roger Uwate and Dr. Barbara Kojis.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 11
Period: April 2002 June 2003


LITERATURE CITED

Acosta, C.A. & M.J. Butler. 1997. Role of mangrove habitat as a nursery for juvenile
spiny lobster, Panulirus argus, in Belize. Mar. Freshwater Res. 48, 721-727.

Acosta, C.A., T.R. Matthews, & M.J. Butler. 1997. Temporal patterns and transport
processes in recruitment of spiny lobster (Panulirus argus) postlarvae to south Florida. Mar.
Bio. 129, 79-85.

Andree, S. 1981. Locomotory activity patterns and food items of benthic postlarval spiny
lobsters, Panulirus argus. Mar. Sci. thesis, Florida State University, Tallahassee. (cited
unseen from Herrnkind and Butler 1986).

Bannerot, S.P., J.H. Ryther, & M. Clark. 1992. Largse-scale assessment of recruitment
of postlarval spiny lobsters, Paulirus argus, to Antigua, West Indies. GulfCaribb. Fish. Inst.
41: 471-486.

Bertelsen, R.D. & T.R. Matthews. 2001. Fecundity dynamics of female spiny lobster
(Panulirus argus) in a south Florida fishery and Dry Tortugas National Park lobster
sanctuary. Mar. Freshwater Res. 52, 1559-65.

Bolden, S.K. 2001. Status of the U.S. Caribbean spiny lobster fishery 1980-1999.
USDOC/NMFS, Miami Laboratory Contribution No. PRD-99/00-17, 69 pp.

Butler, M.J. & W.F. Herrnkind. 1997. A test of recruitment limitation and the potential
for artificial enhancement of spiny lobster (Panulirus argus) populations in Florida. Can. J.
Fish. Aquat. Sci. 54, 452-463.

Butler, M.J., W.F., Herrkind, & J.H. Hunt. 1997. Factors affecting the recruitment of
juvenile Caribbean spiny lobsters dwelling in macroalgae. Bull. Mar. Sci. 61(1), 3-19.

Caddy. 1986. Modelling stock-recruitment processes in Crustacea: some practical and
theoretical perspectives. Can. J. ofFish. Aquat. Sci. 43, 2330-44. (cited unseen from
Herrnkind, W.F., M.J. Butler, J.H. Hunt, & M. Childress, 1997).

Caribbean Community Secretariat (CARICOM). 1996. Lobster and conch subproject
specification and training workshop proceedings. Caribbean Community Fishery Research
Document No. 19, 263 pp.

Cruz, R., M.E. de Leon, & R. Puga. 1995. Prediction of commercial catches of the
spiny lobster Panulirus argus in the Gulf of Batabano, Cuba. Proceedings of the Fourth
International Workshop on Lobster Biology and Maganement, 1993. Crustaceana 68(2),
238-244. (cited unseen from Caribbean Community Secretariat, 1996).






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 12
Period: April 2002 June 2003


Heatwole, D.W., J.H. Hunt, & B.I. Blonder. 1992. Offshore recruitment of postlarval
spiny lobster, Panulirus argus, at Looe Key reef, Florida. Proc. Annu. GulfCaribb. Fish.
Inst. 40, 429-433.

Herrnkind, W.F. & M.J. Butler. 1986. Factors regulating postlarval settlement and
juvenile microhabitat use by spiny lobsters Panulirus argus. Mar. Ecol. Prog. Ser. vol. 34,
23-30.

Herrnkind, W.F., M.J. Butler, J.H. Hunt, & M. Childress. 1997. Role of physical refugia:
implications from a mass sponge die-off in a lobster nursery in Florida. Mar. Freshwater
Res. 48, 759-769.

Kittaka, J. 1994. Larval rearing. In Spiny lobster management. Edited by B.F. Phillips,
J.S. Cobb, and J. Kittaka. Blackwell Scientific Press, Oxford. pp. 402-423.

Kojis, B.L., N.J. Quinn, & S.M. Caseau. 2003. Recent settlement trends in Panulirus
argus (Decapoda: Palinuridae) pueruli around St. Thomas, U.S. Virgin Islands. Rev. Biol.
Trop., 51(4), 17-24.

Lewis, J.B., Moore, H.B., & W. Babis. 1952. The postlarval stages of the spiny lobster
Panularus argus. Bull. Mar. Sci. 2, 324-337.

Little, E.J. 1977. Observations on recruitment of post larval spiny lobsters, Panulirus
argus, to the South Florida coast. Fla. Mar. Res. Publ. No. 29, 35 pp.

Lozano-Alvarez, E., P. Briones-Fourzan, & F. Negrete-Soto. 1994. An evaluation of
concrete block structures as shelter for juvenile Caribbean spiny lobsters, Panulirus argus.
Bull. Mar. Sci. 55(2-3), 351-362.

Lyons, W.G. 1980. Possible sources of Florida's spiny lobster population. Proc. Gulf
Caribb. Fish. Inst. 33, 253-266.

Mateo, I. & W.J. Tobias. 2001. Preliminary estimations of growth, mortality and yield
per recuit for the spiny lobster Panulirus argus in st. Croix, USVI. Proc. GulfCaribb. Inst.
53, (in press).

Olsen, D.A., W.F. Herrnkind & R.A. Cooper. 1975. Population dynamics, ecology and
behavior of spiny lobsters, Panulirus argus, of St. John, USVI. Results of the Tektite
program: coral reef invertebrates and plants. Nat. Hist. Mus. Ang. Cty. Sci. Bull 20, 11-16.

Quinn, N.J. & B.L. Kojis. 1995. Use of artificial shelters to increase lobster production in
the US Virgin Islands, with notes on the use of shelters in Mexican waters. Carib. J. Sci. 31,
311-316.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 13
Period: April 2002 June 2003


Quinn, N.J. & B.L. Kojis. 1997. Settlement variations of the spiny lobster (Panulirus
argus) on Witham collectors in Caribbean coastal waters around St. Thomas, United States
Virgin Islands. Carib. J. Sci. 33, 251-262.

Sosa-Cordero, E., A.M. Arce, W. Aguilar-Davila, & A. Ramirez-Gonzalez. 1998.
Artificial shelters for spiny lobster panulirus argus (Latreilla): an evaluation of occupancy in
different benthic habitats. J. Exp. Mar. Biol. Ecol. 229, 1-18.

Spanier, E., and R.K. Zimmer-Fraust. 1988. Some physical properties of shelter that
influence den preferences in spiny lobsters. J. Exp. Mar. Biol. Ecol. 121, 137-149.

Wahle, R. & R.S. Steneck. 1991. Recruitment habitats and nursery grounds of the
American lobster Homarus americanus: a demographic bottleneck? Mar. Ecol. Prog. Ser. 69,
231-243.

Witham, R., R.M. Ingle, & E.A. Joyce Jr. 1968. Physiological and ecological studies of
Panulirus argus from the St. Lucie estuary. Fla. Board. Cons. Mar. Res. Lab. Tech. Ser. No.
53, 31 pp.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 14
Period: April 2002 June 2003









-Hair" Filters (40.5 cm x 61 cm) 1.90 cm diameter PVC Pipe
<{ ,! ,,- J .

t" : : . .. .'?.; ,' . .KLI



,* ,.,'' ,,II:
.':.' ..*.. -f 'I" .. I ...., L

Witham Collector with "Hogs PVC Frame 40.5 x 40.5 cm with
Hair" Filters (40.5 cm x 61 cm) 1.90 cm diameter PVC Pipe
Figure 1. Modified Witham collector used in lobster pueruli settlement study (figures not drawn to
scale).






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Figure 2. Map of St. Thomas east end showing the locations of the 5 lobster pueruli collection sites
and the 1 juvenile shelter station (locations of pueruli collections detailed in Appendix 1,
locations of juvenile lobster attractors detailed in Appendix 3).


Type : Uncovered
Type 1: Uncovered


Type 2: Covered


Figure 3. Two types of concrete block shelters used in juvenile lobster study (single block: 40 cm x
20 cm x 15 cm, cover ~ 80 x 80 cm, figures not to scale).


N


\


1, \ A2
. '... : ^


Cow & Calf Rocks

Juvenile shelters







SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


200


160


120


80


IE-


Mangrowe
Lagoon


Figure 4. Total catch of Panulirus argus pueruli settlement on Witham colletors by site, 2002-2003.





Mangrove Lagoon
2.00



1.50



1.00



0.50



0.00
o o 0 0 0 0 0 0 0 0 0 0




Figure 5. Catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/number of Witham collectors) for the Mangrove Lagoon site (n=27) during the
study period between 18 June 2002 and 17 June 2003.


Cas Cay Nazareth Northwest
Bay Great St.
James


Southwest
Great St.
James








SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Cas Cay


2.00




1.50




p 1.00




0.50


0.00 Cl Cl cN c m
0 0 0 0 0 0 0 0 0 0


C\ (^ 00 O O O 0 C- C(N C- -N m t /


Figure 6. Catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/ number of Witham collectors) for the Cas Cay site (n=24) during the study
period between 18 June 2002 and 17 June 2003. Gaps in data are due to broken or lost
collectors.


Nazareth Bay


2.00



1.50




1.00



0.50



0.00


0 0
C'1 C'1
00 00
\D t-~-


0 0
00 00
0o. 0


0 0
00 00
(


0 0 0
00 00 00
- C Ci C


Figure 7. Catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/ number of Witham collectors) for the Nazareth Bay site (n=27) during the study
period between 18 June 2002 and 17 June 2003.








SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003



Northwest Great St James


2.00



1.50


W
S1.00




0.50



0.00

cq cq c


Cl Cl
0\ 0


CO CO
Cl Cl c3
0 0 0
00 00 00
Cl^


Figure 8. Catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/number of Witham collectors) for the northwest St. James site (n=27) during the
study period between 18 June 2002 and 17 June 2003.





Southwest Great St. James


2.00



1.50



. 1.00



0.50


nnn


Bc B


'0


r ~ 00 0


Figure 9. Catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/number of Witham collectors) for the southwest St. James site (n=27) during the
study period between 18 June 2002 and 17 June 2003.


~~* .........


0 0
00 00
Cl m


C~i C~
0 0
00 00
ot C)
3 3


U'_ ~ __ 333 33 3U ---


jh


1-


M M






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003



0.50

0.40

0.30

0.20

0.10

0.00 -r l
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec


Mean catch per unit effort (CPUE = number of pueruli/number of days between sample
periods/number of Witham collectors) on Witham collectors summed over all sites and
months, 2002-2003.


NM*1 FQM*1


FM*1


LQM*1


NM*1


1 10 20 30
Days After New Moon
Lunar pattern of settlement of pueruli Panulirus argus on Witham collectors at all sites
during 2002-2003 based on catch per unit effort (CPUE = number of pueruli/number of
days between sample periods/number of Witham collectors, Std. Dev.). *Notes: (1)


Figure 10.


Figure 11.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003

New Moon Phase, First Quarter Phase, Full Moon Phase, Last Quarter Phase, New
Moon Phase.


Mangrove Lagoon


Jan Feb Mar April May June July Aug Sept Oct Nov Dec


Monthly comparison of catch per unit effort (CPUE = number of pueruli/number of
days between sample periods/number of Witham collectors) of Panulirus argus pueruli
settlement on Witham collectors among years for Inner Mangrove Lagoon. *Note:
1992-1993 data from Quinn and Kojis (1997); 1997-1998 data From Kojis et al. (2003).


Cas Cay


Jan Feb Mar April May June July Aug Sept Oct Nov Dec


Monthly comparison of catch per unit effort (CPUE = number of pueruli/number of
days between sample periods/number of Witham collectors) of Panulirus argus pueruli
settlement on Witham collectors among years for Cas Cay. *Note: 1997-1998 data
from Kojis et al. (2003).


Figure 12.


Figure 13.





SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Nazareth Bay


0.80

0.60

0.40

0.20


0.00


-2002-2003
1997-1998*

iT^ ,-h


LZ


I/ A /A


Jan Feb Mar April May June July Aug Sept Oct Nov Dec


Monthly comparison of catch per unit effort (CPUE = number of pueruli/number of
days between sample periods/number of Witham collectors) of Panulirus argus pueruli
settlement on Witham collectors among years for Nazareth Bay. *Note: 1997-1998
data from Kojis et al. (2003).


Great St. James


Jan Feb Mar April May June July Aug Sept Oct Nov Dec


Monthly comparison of catch per unit effort (CPUE = number of pueruli/number of days
between sample periods/number of Witham collectors) of Panulirus argus pueruli
settlement on Witham collectors among years for Great St. James Island. Northwest
and southwest Great St. James sites were combined for comparison to previous years.


Figure 14.


Figure 15.


-


ai~


t^a&






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 2
Period: April 2002 June 2003

*Note: 1992-1993 data from Quinn and Kojis (1997); 1997-1998 data from Kojis et al.
(2003).



0.50 I


0.40

0.30

0.20

0.10


Mangrove
Lagoon


Cas Cay *(')


Nazareth Bay *(') Great St. James
Island *(2)


Comparison of catch per unit effort (CPUE = number of pueruli/number of days
between sample periods/number of Witham collectors) on Witham collectors among
common sites between 1992-2003. *Notes: (1) Cas Cay and Nazareth Bay were not
sampled in 1992-1993; (2) For 2002-2003, Great St. James sites were combined for
comparison to previous years; (3) 1992-1993 data from Quinn and Kojis (1997); 1997-
1998 data cited from Kojis et al. (2003).


Table 1. Number of Panulirus argus pueruli on Witham collectors of different stages settling
at each site, 2002-2003.
Site n* Transparent Semi- Pigmented Juvenile Total
pigmented
Mangrove Lagoon 27 0 1 0 18 19

Cas Cay 24 0 4 0 14 18

Nazareth Bay 27 8 10 25 84 127

Northwest Great St. James 27 1 3 0 6 10

Southwest Great St. James 27 1 1 3 23 28

Totals (132) 132 10 19 28 145 202
*Note: n = total number of samples per site.


O 1992-1993 *(3)
O 1997-1998 (3)
* 2002-2003


Figure 16.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Table 2. Abundance of Panulirus argus pueruli on Witham collectors, 2002-2003, as associated
to lunar phase and the combined mean catch per unit effort (CPUE = number of
pueruli/number of days between sample periods/number of Witham collectors) for
each phase.
Site Total number Total number Total number Total number
of pueruli of pueruli of pueruli of pueruli
new moon first quarter full moon last quarter
(n = 2)*1 (n = 11)*1 (n = 5)*1 (n = 9)*1
Mangrove Lagoon 2 15 1 1
CasCay 2 15 1 0

Nazareth Bay 16 91 5 15

Northwest Great St James 0 6 3 1

Southwest Great St James 2 21 0 5

Totals 22 148 10 22

Combined CPUE 0.09 0.21*2 0.10 0.24*2 0.02 0.03*2 0.02 0.07*2

*Notes: (1) n = total number of lunar phases.
(2) Standard Deviation of the mean


Table 3. Mean annual catch per unit effort (CPUE = number of pueruli/number of days
between sample periods/number of Witham collectors) on Witham collectors by
site between years, 1992-2003.
Site Mean Annual CPUE (+SD) Combined
Mean
Year Mangrove Nazareth Great St. Annual
Lagoon Bay James CPUE
(SD)
1992-1993*' 0.23 + 0.30 *3 *3 0.16 + 0.30 0.20 + 0.29

1997-1998*2 0.09 + 0.10 0.21 + 0.31 0.30 + 0.46 0.02 + 0.04 0.15 + 0.30

2002-2003 0.03 + 0.04 0.03 + 0.05 0.17 + 0.35 0.03 + 0.04 0.07 + 0.19

* Notes: (1) 1992-93 data reworked from DFW database.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 2,
Period: April 2002 June 2003

(2) 1997-98 data reworked from DFW database.
(3) Cas Cay and Nazareth Bay were nonexistent sites in 1992-1993.


Table 4. Number of juvenile Panulirus argus residing in ten juvenile lobster shelters deployed
southeast of Cow & Calf, St. Thomas, 2002/2003.
Date No. of No. of No. of No. of
Uncovered Lobsters Covered Lobsters
Shelter* Shelter*
September 2002 10 0

December 2002 10 1

March 2003 5 0 5 0

June 2003 5 0 5 1

Total Lobsters 1 1
*Note: All shelters were uncovered in September and December 2002. Covers were
deployed in December 2002 after sampling.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 1. U.S. Virgin Islands pueruli settlement sites, GPS coordinates,
habitat and depths, 2002-2003
Sites Habitat Depth WAAS GPS Location
(m) Lattitude Longitude
Inner Mongrove Lagoon Seagrass/Algae 2.0 180 18.333'N 640 52.474'W

Cas Cay Seagrass/Algae 1.5 180 18.548'N 640 52.118'W

Nazareth Bay Patchy Seagrass/Sand 6.1 180 19.069'N 640 51.416'W

Northwest Great Patchy Coral 8.2 180 18.794'N 640 49.975'W
St. James Reef/Sand

Southwest Great Patchy Seagrass/Sand 10.6 180 18.403'N 640 50.140'W
St. James







Appendix 2. Stage categories of the Caribbean spiny lobster (Panulirus argus) puerulus
Category* Description
Transparent No body pigment; only eye pigmented

Semi-pigmented Light lateral pigmentation, limited to base of antennas with faint
pigmentation at base of antennas and sides of carapace and along
sides of tail; body dorso-ventrally depressed

Pigmented Laterally pigmented (well-defined light brown color); light stripe
extending the length of the carapace and tail; body depressed

Algal-phase Juvenile First post-puerulus stage/early benthic stage (body undergone one
molt), dark band runs along side of the body; 5-15 mm carapace
length (CL), this phase remain for a few months in vegetation, where
they are sheltered from predators

*Note: Stage descriptions are from Bannerot, et al. (1992); CARICOM (1996); and
Butler and Hermkind (1997).






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 3. U.S. Virgin Islands Juvenile Lobster Shelter Station, 2002-2003
Block Set Bearing from Distance (m) to next Depth WAAS GPS location of
No. next block set block set from (m) ending buoys (1)
previous set Lattitude Longitude

1 1300 (2) 31.8 20
2 1650 29.4 20 180 17.986'N 640 50.230'W
3 450 33.3 20
4 1400 33.3 20
5 95 40.9 20
6 1150 31.8 20
7 980 32.4 20
8 95 37.6 20
9 920 38.2 20
10 -- -- 20 180 17.998'N 64 50.375'W
*Notes: (1) GPS coordinates were recorded only for juvenile lobster shelters 2 and 10.
(2) This bearing starts at block set number 2.







SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 4. Settlement by stages of P. argus pueruli at all sites.
Mangrove Lagoon
Collector 1 Collector 2 Catch
semi- Catch semi- Catch
Date transparent sem- pigmented juvenile t transparent saet pigmented juvenile total Total
Date transparent total transparent total
4 Jun 02*
18Jun02 0 0 0 2 2 0 0 0 0 0 2
1 Jul02 0 0 0 0 0 0 0 0 0 0 0
16 Jul 02 0 0 0 2 2 0 0 0 1 1 3
30Jul02 0 0 0 0 0 0 0 0 0 0 0
13Aug02 0 0 0 0 0 0 0 0 2 2 2
27Aug02 0 0 0 0 0 0 0 0 0 0 0
10Sep02 0 0 0 0 0 0 0 0 0 0 0
26Sep02 0 0 0 0 0 0 0 0 0 0 0
8 Oct02 0 0 0 0 0 0 0 0 0 0 0
22Oct02 0 0 0 0 0 0 0 0 2 2 2
6 Nov 02 0 0 0 0 0 0 0 0 0 0 0
19Nov02 0 0 0 0 0 0 0 0 0 0 0
3 Dec 02 0 0 0 0 0 0 0 0 0 0 0
17 Dec 02 0 0 0 0 0 0 0 0 0 0 0
30 Dec 02 0 0 0 0 0 0 0 0 0 0 0
14 Jan 03 0 0 0 0 0 0 0 0 0 0 0
28 Jan 03 0 0 0 1 1 0 0 0 0 0 1
11Feb03 0 0 0 0 0 0 0 0 0 0 0
26Feb03 0 0 0 0 0 0 0 0 0 0 0
11 Mar 03 0 0 0 0 0 0 0 0 0 0 0
25 Mar 03 0 0 0 0 0 0 0 0 0 0 0
8 Apr 03 0 0 0 0 0 0 0 0 0 0 0
23Apr03 0 0 0 0 0 0 0 0 0 0 0
6May 03 0 0 0 0 0 0 0 0 4 4 4
22May 03 0 1 0 1 2 0 0 0 0 0 2
4 Jun 03 0 0 0 1 1 0 0 0 1 1 2
17 Jun 03 0 0 0 1 1 0 0 0 0 0 1
Totals 0 1 0 8 9 0 0 0 10 10 19
*Note: Collectors were installed on 4 June 03 thus no sample was taken on this date






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 4 continued. Settlement by stages of P. argus pueruli at all sites.
Cas Cay
Collector 1 Collector 2 Site
semi- Catch semi- Catch
Date transparent s pigmented juvenile a transparent sem- pigmented juvenile Ch Catch
Date transparent total transparent total
4-Jun 02*1
18 Jun 02 0 0 0 3 3 0 0 0 0 0 3
1 Jul02 0 0 0 0 0 0 0 0 0 0 0
16 Jul 02 0 0 0 2 2 0 0 0 1 1 3
30 Jul 02 0 0 0 0 0 0 0 0 0 0 0
13Aug 02 0 0 0 1 1 0 0 0 0 0 1
27Aug 02 0 0 0 0 0 0 0 0 0 0 0
10Sep 02 0 0 0 2 2 0 0 0 1 1 3
26 Sep 02 *2 *2 *2 0 0 0 0 0 0
80ct02 0 0 0 0 0 0 0 0 0 0 0
22Oct02 0 0 0 0 0 0 0 0 1 1 1
6 Nov 02 *2 *2 *2 *2 *2 *2 *2 *2 *2 *2 *2
19 Nov 02 0 0 0 0 0 *2 2 ,2 ,2 2 0
3 Dec 02 0 2 0 0 2 0 0 0 0 0 2
17 Dec 02 *2 *2 *2 *2 *2 *2 *2 *2 *2 *2 *2
30 Dec 02 0 0 0 0 0 0 0 0 0 0 0
14 Jan 03 0 1 0 1 2 0 0 0 0 0 2
28 Jan 03 0 0 0 0 0 0 0 0 0 0 0
11 Feb 03 0 0 0 0 0 0 0 0 0 0 0
26 Feb 03 *2 *2 *2 *2 *2 *
11 Mar 03 0 0 0 0 0 0 1 0 0 1 1
25 Mar 03 *2 *2 *2 *2 *2 0 0 0 0 0 0
8 Apr 03 0 0 0 0 0 *2 0
23 Apr 03 0 0 0 0 0 0 0 0 0 0 0
6 May 03 0 0 0 2 2 *2 2
22 May 03 0 0 0 0 0 0 0 0 0 0 0
4 Jun 03 0 0 0 0 0 0 0 0 0 0 0
17 Jun 03 *2 *2 *2 *2 *2 0 0 0 0 0 0
Totals 0 3 0 11 14 0 1 0 3 4 18
bhT,+,, /1\ ll1, i ,,, '^^^ ^ll^J d hl l k hi d..^ -! 1,^^ l- ,


Notes: (1) Co sectors were nsta e on 4 Jun
(2) Collectors were found broken and either c ragging on the bottom or comp etely


detached or missing from the mooring.


;i






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 4 continued. Settlement stages of P. argus pueruli at all sites.
Nazareth Bay
Collector 1 Collector 2
semi- Catch semi- Catch Site
Date transparent transparent pigmented juvenile total transparent transparent pigmented juvenile total Catch
4-Jun 02*
18 Jun 02 1 0 3 0 4 1 1 6 0 8 12
1 Jul02 0 0 0 0 0 0 0 0 0 0 0
16 Jul 02 0 0 0 3 3 0 0 0 0 0 3
30Jul02 0 0 0 0 0 0 0 0 0 0 0
13Aug02 0 0 0 0 0 0 0 0 0 0 0
27Aug02 0 0 0 0 0 0 0 0 1 1 1
10 Sep02 0 0 0 0 0 0 2 1 2 5 5
26 Sep02 0 0 0 0 0 0 0 0 1 1 1
8 Oct02 0 1 2 8 11 1 0 1 3 5 16
22Oct02 0 0 0 4 4 0 0 0 0 0 4
6 Nov 02 0 0 0 1 1 0 0 0 0 0 1
19Nov02 0 0 0 0 0 0 0 0 0 0 0
3 Dec 02 0 0 0 0 0 0 0 0 0 0 0
17 Dec 02 0 0 0 0 0 0 0 0 0 0 0
30 Dec 02 0 0 0 0 0 0 0 0 0 0 0
14 Jan 03 0 0 0 1 1 0 0 0 0 0 1
28 Jan 03 0 0 0 0 0 0 0 0 0 0 0
11Feb03 0 0 0 0 0 0 0 0 0 0 0
26Feb03 0 0 0 0 0 0 0 0 0 0 0
11 Mar 03 0 0 0 0 0 0 0 0 0 0 0
25 Mar 03 0 0 0 0 0 0 0 0 12 12 12
8 Apr 03 1 0 1 8 10 2 0 0 13 15 25
23Apr03 1 0 0 0 1 0 0 0 0 0 1
6 May 03 0 1 3 6 10 1 4 8 17 30 40
22May 03 0 0 0 2 2 0 0 0 0 0 2
4Jun03 0 1 0 2 3 0 0 0 0 0 3
17Jun03 0 0 0 0 0 0 0 0 0 0 0
Totals 3 3 9 35 50 5 7 16 49 77 127
*Note: Collectors were installed on 4 June 03 thus no sample was taken on this date.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 4 continued. Settlement stages of P. argus pueruli at all sites.
Northwest St James
Collector 1 Collector 2
semi- Catch semi- Catch Site
Date transparent transparent pigmented juvenile total transparent transparent pigmented juvenile total Catch
4 Jun 02*
18Jun02 0 0 0 0 0 0 0 0 0 0 0
1 Jul02 0 0 0 0 0 0 0 0 1 1 1
16 Jul 02 0 0 0 0 0 0 0 0 0 0 0
30 Jul 02 0 0 0 0 0 0 0 0 0 0 0
13Aug02 0 0 0 0 0 0 0 0 0 0 0
27Aug02 0 0 0 0 0 0 0 0 0 0 0
10Sep02 0 0 0 0 0 0 0 0 0 0 0
26Sep02 0 0 0 0 0 0 0 0 0 0 0
8 Oct02 0 0 0 0 0 0 0 0 0 0 0
22Oct02 0 0 0 1 1 0 0 0 0 0 1
6 Nov 02 0 0 0 0 0 0 0 0 0 0 0
19Nov02 0 0 0 1 1 0 0 0 0 0 1
3 Dec 02 0 0 0 0 0 0 0 0 0 0 0
17 Dec 02 0 0 0 0 0 0 0 0 0 0 0
30 Dec 02 0 0 0 0 0 0 0 0 0 0 0
14 Jan 03 0 0 0 0 0 0 0 0 1 1 1
28 Jan 03 0 0 0 0 0 0 0 0 0 0 0
11Feb03 0 0 0 0 0 0 0 0 0 0 0
26Feb03 0 0 0 0 0 0 0 0 0 0 0
11 Mar 03 0 0 0 0 0 0 0 0 0 0 0
25 Mar 03 0 0 0 0 0 0 0 0 1 1 1
8 Apr 03 0 0 0 0 0 0 1 0 0 1 1
23Apr03 0 0 0 0 0 0 0 0 0 0 0
6May 03 1 1 0 0 2 0 1 0 0 1 3
22May 03 0 0 0 0 0 0 0 0 0 0 0
4 Jun 03 0 0 0 0 0 0 0 0 0 0 0
17 Jun 03 0 0 0 0 0 0 0 0 1 1 1
Totals 1 1 0 2 4 0 2 0 4 6 10
*Note: Collectors were installed on 4 June 03 thus no sample was taken on this date.






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 4 continued. Settlement stages of P. argus pueruli at all sites.
Soutlihest St. Jamnes
Collector 1 Collector 2
semi- Catch semi- Catch Site
Date transparent transparent pigmented juvenile total transparent transparent pigmented juvenile total Catch
4 Jun 02*1
18Jun02 0 0 0 3 3 0 0 3 3 6 9
1 Jul02 0 0 0 0 0 0 0 0 0 0 0
16 Jul 02 0 0 0 4 4 0 0 0 1 1 5
30 Jul 02 0 0 0 0 0 0 0 0 1 1 1
13Aug02 0 0 0 0 0 0 0 0 0 0 0
27 Aug 02 0 0 0 1 1 0 0 0 1 1 2
1 Sep 02 0 0 0 0 0 0 0 0 0 0 0
26Sep02 0 0 0 0 0 0 0 0 0 0 0
8 Oct02 0 0 0 2 2 0 0 0 0 0 2
22 Oct02 0 0 0 0 0 0 0 0 0 0 0
6Nov02 0 0 0 0 0 0 0 0 0 0 0
19Nov02 0 0 0 0 0 0 0 0 0 0 0
3Dec02 0 0 0 0 0 0 0 0 0 0 0
17 Dec 02 0 0 0 0 0 0 0 0 0 0 0
30 Dec 02 0 0 0 0 0 0 0 0 0 0 0
14 Jan 03 0 0 0 0 0 0 0 0 0 0 0
28 Jan 03 0 0 0 0 0 0 0 0 0 0 0
11 Feb 03 0 0 0 0 0 *2 *2 *2 *2 *2 0
26 Feb 03 1 0 0 0 1 0 0 0 0 0 1
11 Mar 03 0 0 0 0 0 0 0 0 1 1 1
25 Mar 03 0 0 0 0 0 0 0 0 0 0 0
8Apr03 0 0 0 0 0 0 0 0 0 0 0
23 Apr 03 0 0 0 0 0 0 0 0 1 1 1
6 May 03 0 1 0 0 1 0 0 0 3 3 4
22May 03 0 0 0 1 1 0 0 0 0 0 1
4 Jun 03 0 0 0 0 0 0 0 0 1 1 1
17 Jun 03 0 0 0 0 0 0 0 0 0 0 0
Totals 1 1 0 11 13 0 0 3 12 15 28


detached or missing from the mooring.


*Notes: (1) Collectors were installed on 4 June 03 thus no sample was taken on this data.
(2) Collectors were found broken and either dragging on the bottom or completely







SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 5. Catches and catch per unit effort (CPUE = number of pueruli/number of days in sample period/number of collectors)
for of P. argus pueruli at each site (2002-2003).
Inner Mangrove Lagoon Cas Cay Nazareth Bay
Catch Catch Catch
Date Collector 1 Collector 2 total CPUE Collector 1 Collector 2 total CPUE Collector 1 Collector 2 total CPUE
4 Jun 02*1
18 Jun 02 2 0 2 0.07 3 0 3 0.11 4 8 12 0.43
1 Jul 02 0 0 0 0.00 0 0 0 0.00 0 0 0 0.00
16 Jul 02 2 1 3 0.10 2 1 3 0.10 3 0 3 0.10
30 Jul 02 0 0 0 0.00 0 0 0 0.00 0 0 0 0.00
13 Aug 02 0 2 2 0.07 1 0 1 0.04 0 0 0 0.00
27 Aug 02 0 0 0 0.00 0 0 0 0.00 0 1 1 0.04
10 Sep02 0 0 0 0.00 2 1*2 2 0.14 0 5 5 0.18
26 Sep02 0 0 0 0.00 *2 0 0 0.00 0 1 1 0.03
8 Oct 02 0 2 2 0.08 0 0 0 0.00 11 5 16 0.67
22 Oct 02 0 0 0 0.00 0 1 1 0.04 4 0 4 0.14
6 Nov 02 0 0 0 0.00 *2 *2 1 0 1 0.03
19 Nov 02 0 0 0 0.00 0 *2 0 0.00 0 0 0 0.00
3 Dec 02 0 0 0 0.00 2 0 2 0.07 0 0 0 0.00
17 Dec 02 0 0 0 0.00 *2 *2 *2 0 0 0.00
30 Dec 02 0 0 0 0.00 0 0 0 0.00 0 0 0 0.00
14 Jan 03 0 0 0 0.00 2 0 2 0.07 1 0 1 0.03
28 Jan 03 1 0 1 0.04 0 0 0 0.00 0 0 0 0.00
11 Feb 03 0 0 0 0.00 0 0 0 0.00 0 0 0 0.00
26 Feb 03 0 0 0 0.00 *2 *2 0 0 0 0.00
11 Mar 03 0 0 0 0.00 0 1 1 0.04 0 0 0 0.00
25 Mar 03 0 0 0 0.00 *2 0 0 0.00 0 12 12 0.43
8 Apr 03 0 0 0 0.00 0 *2 0 0.00 10 15 25 0.89
23 Apr 03 0 0 0 0.00 0 0 0 0.00 1 0 1 0.03
6 May 03 0 4 4 0.15 2 *2 2 0.15 10 30 40 1.54
22 May 03 2 0 2 0.06 0 0 0 0.00 2 0 2 0.06
4 Jun 03 1 1 2 0.08 0 0 0 0.00 3 0 3 0.12
17 Jun 03 1 0 1 0.04 *2 0 0 0.00 0 0 0 0.00
Totals 9 10 19 14 3 17 50 77 127
*Notes: (1) Collectors were installed on 4 June 03 thus no sample was taken on this date.
(2) Collector was found broken and either dragging on the bottom or was completely detached from the mooring, therefore
sample was discarded from analysis.







SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 5 (continued). Catches and catch per unit effort (CPUE = number of pueruli/number of days in sample
period/number of collectors) for of P. argus pueruli at each site (2002-2003).
Noriliest St. Jimes Soulti est St. James
Collector 1 Collector 2 Catch total CPUE Collector 1 Collector 2 Catch total CPUE
4 Jun 02*1
18 Jun 02 0 0 0 0.00 3 6 9 0.32
1 Jul 02 0 0 0 0.00 0 0 0 0.00
16 Jul 02 0 1 1 0.03 4 1 5 0.17
30 Jul 02 0 0 0 0.00 0 1 1 0.04
13 Aug 02 0 0 0 0.00 0 0 0 0.00
27 Aug 02 0 0 0 0.00 1 1 2 0.07
10 Sep 02 0 0 0 0.00 0 0 0 0.00
26 Sep 02 0 0 0 0.00 0 0 0 0.00
8 Oct 02 0 0 0 0.00 2 0 2 0.08
22 Oct 02 1 0 1 0.04 0 0 0 0.00
6 Nov 02 0 0 0 0.00 0 0 0 0.00
19 Nov 02 1 0 1 0.04 0 0 0 0.00
3 Dec 02 0 0 0 0.00 0 0 0 0.00
17 Dec 02 0 0 0 0.00 0 0 0 0.00
30 Dec 02 0 0 0 0.00 0 0 0 0.00
14 Jan 03 0 1 1 0.03 0 0 0 0.00
28 Jan 03 0 0 0 0.00 0 0 0 0.00
11 Feb 03 0 0 0 0.00 0 *2 0 0.00
26 Feb 03 0 0 0 0.00 1 0 1 0.03
11 Mar 03 0 0 0 0.00 0 1 1 0.04
25 Mar 03 0 1 1 0.04 0 0 0 0.00
8 Apr 03 0 1 1 0.04 0 0 0 0.00
23 Apr 03 0 0 0 0.00 0 1 1 0.03
6 May 03 2 1 3 0.12 1 3 4 0.15
22 May 03 0 0 0 0.00 1 0 1 0.03
4 Jun 03 0 0 0 0.00 0 1 1 0.04
17 Jun 03 0 1 1 0.04 0 0 0 0.00
Totals 4 6 10 _13 15 28
*Notes: (1) Collectors were installed on 4 June 03 thus no sample was taken on this date.
(2) Collector was found broken and either dragging on the bottom or was completely detached from the mooring,
therefore sample was discarded from analysis






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report 3z
Period: April 2002 June 2003

Appendix 6. Test by site on catch per unit effort (CPUE = number of pueruli/number of sample
days/number of collectors) for the year 2002-2003.


One Way Analysis of Variance
Normality Test: Failed (P
Equal Variance Test: Passed (P


<0.001)
0.430)


Group
lagoon
cas cay
nazareth
nw st james
sw stjames

Group
lagoon
cas cay
nazareth
nw stjames
sw stjames


Missing
0


Mean
0.0257
0.0313
0.175
0.0136
0.0373


Std Dev
0.0419
0.0492
0.353
0.0258
0.0725


SE of Mean
0.00806
0.0100
0.0679
0.00497
0.0140


Power of performed test with alpha = 0.050: 0.841


Source of Variation DF SS MS
Between Treatments 4 0.479 0.120
Residual 127 3.491 0.027
Total 131 3.969


F P
4.355 0.002


The differences in the mean values among the treatment groups are greater than would be
expected by chance; there is a statistically significant difference (P = 0.002).

All Pairwise Multiple Comparison Procedures (Tukey Test):


Comparisons for factor:
Comparison
nazareth vs. nw st james
nazareth vs. lagoon
nazareth vs. cas cay
nazareth vs. sw st james
sw st james vs. nw st james
sw stjames vs. lagoon
sw stjames vs. cas cay
cas cay vs. nw st james
cas cay vs. lagoon
lagoon vs. nw st james


Diff of Means
0.161
0.149
0.144
0.138
0.0237
0.0116
0.00598
0.0178
0.00564
0.0121


q
5.056
4.676
4.365
4.312
0.744
0.364
0.182
0.540
0.171
0.380


P<0.05
Yes
Yes
Yes
Yes
No
No
No
No
No
No






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003


Appendix 7.


Two Way analysis of variance for site and year (because not all site were sampled
in all years, some treatments were missing therefore there was no test for
interactions)


General Linear Model (No Interactions)
Dependent Variable: CPUE (CPUE = total catch / number of sample days / number of collectors)
Normality Test: Failed (P = <0.001)
Equal Variance Test: Passed (P = 0.083)


Source of Variation
year
site
Residual
Total


DF SS
2 1.398
3 1.695
280 17.987
285 20.459


MS
0.699
0.565
0.0642
0.0718


F P
10.881 <0.001
8.798 <0.001


The difference in the mean values among the different levels of year is greater than would be
expected by chance after allowing for effects of differences in site. There is a statistically
significant difference (p = <0.001). To isolate which groups) differ from the others use a
multiple comparison procedure.

The difference in the mean values among the different levels of site is greater than would be
expected by chance after allowing for effects of differences in year. There is a statistically
significant difference (p = <0.001). To isolate which groups) differ from the others use a
multiple comparison procedure.


Power of performed test with alpha =
Power of performed test with alpha =

Least square means for year
Group Mean SEM
2003.000 0.0657 0.0248
1998.000 0.150 0.0242
1992.000 0.265 0.0353


Least square means for site
Group Mean
1.000 0.113
2.000 0.167
3.000 0.292
4.000 0.0682


0.0500: for year: 0.990
0.0500: for site : 0.993


SEM
0.0263 (Mangrove Lagoon)
0.0413 (Cas Cay)
0.0354 (Nazareth Bay)
0.0265 (Great St. James)






SEAMAP-C: USVI Spiny Lobster Assessment: Final Report
Period: April 2002 June 2003

Appendix 7 (continued). Two Way analysis of variance for site and year (because not all site
were sampled in all years, some treatments were missing therefore
there was no test for interactions)

All Pairwise Multiple Comparison Procedures (Tukey Test):


Comparisons for factor: year
Comparison Diff of Means p
1992.000 vs. 2003.000 0.199 3
1992.000 vs. 1998.000 0.114 3
1998.000 vs. 2003.000 0.0847


Comparisons for factor: site
Comparison Diff of Means p
3.000 vs. 4.000 0.224 4


q
6.524
3.775
3.462


P<0.05
Yes
Yes
Yes


q P<0.05
7.173 Yes




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