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Importance of Plantations for the Araucaria Tit Spinetail (Leptasthenura setaria) in Argentina

Permanent Link: http://ufdc.ufl.edu/UFE0024179/00001

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Title: Importance of Plantations for the Araucaria Tit Spinetail (Leptasthenura setaria) in Argentina
Physical Description: 1 online resource (32 p.)
Language: english
Creator: Pietrek, Alejandro
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: araucaria, argentina, leptasthenura, plantations
Wildlife Ecology and Conservation -- Dissertations, Academic -- UF
Genre: Wildlife Ecology and Conservation thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: I assessed occupancy and density of the near threatened Araucaria Tit Spinetail (Leptasthenura setaria) in Araucaria forests and Araucaria plantations of Misiones, Argentina. All natural patches were occupied by Araucaria Tit Spinetails and only 85 % of the plantations were occupied. However, density was almost three fold higher in plantations compared to natural forests. In plantations, occupancy was best predicted by age and density by a model including age and isolation. A more detailed analysis showed lower densities in plantations < 10 years old compared to older plantations. Overall, my results indicate that plantations may be good habitat for the Araucaria Tit Spinetail. Restoration of natural remnants and conservation of old, connected plantations in Argentina may assure the protection of significant populations of spinetails and other bird species associated with Araucaria.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Alejandro Pietrek.
Thesis: Thesis (M.S.)--University of Florida, 2009.
Local: Adviser: Branch, Lyn C.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2011-05-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024179:00001

Permanent Link: http://ufdc.ufl.edu/UFE0024179/00001

Material Information

Title: Importance of Plantations for the Araucaria Tit Spinetail (Leptasthenura setaria) in Argentina
Physical Description: 1 online resource (32 p.)
Language: english
Creator: Pietrek, Alejandro
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: araucaria, argentina, leptasthenura, plantations
Wildlife Ecology and Conservation -- Dissertations, Academic -- UF
Genre: Wildlife Ecology and Conservation thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: I assessed occupancy and density of the near threatened Araucaria Tit Spinetail (Leptasthenura setaria) in Araucaria forests and Araucaria plantations of Misiones, Argentina. All natural patches were occupied by Araucaria Tit Spinetails and only 85 % of the plantations were occupied. However, density was almost three fold higher in plantations compared to natural forests. In plantations, occupancy was best predicted by age and density by a model including age and isolation. A more detailed analysis showed lower densities in plantations < 10 years old compared to older plantations. Overall, my results indicate that plantations may be good habitat for the Araucaria Tit Spinetail. Restoration of natural remnants and conservation of old, connected plantations in Argentina may assure the protection of significant populations of spinetails and other bird species associated with Araucaria.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Alejandro Pietrek.
Thesis: Thesis (M.S.)--University of Florida, 2009.
Local: Adviser: Branch, Lyn C.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2011-05-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024179:00001


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1 ASSESSMENT OF THE IMPORTANCE OF PLANTATIONS FOR THE ARAUCARIA TIT SPINETAIL (Leptasthenura setaria ) IN ARGENTINA By ALEJANDRO GERARDO PIETREK 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 2009

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2 2009 Alejandro Gerardo Pietrek

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3 To my parents, Ricardo and Mara Rosa.

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4 ACKNOWLEDGEMENTS I thank Lyn and m embers of my supervis ory committee (Katie and Mary) for their mentoring during these first steps of my professional career. I th ank my family for their loving encouragement which motivated me to complete my thesis, and Pao the cosmic girl who renewed my hope in love. I especially thank al l my friends, who bring joy and happiness to my life.

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5 TABLE OF CONTENTS page ACKNOWLEDGEMENTS.............................................................................................................4 LIST OF TABLES................................................................................................................. ..........6 LIST OF FIGURES.........................................................................................................................7 ABSTRACT.....................................................................................................................................8 CHAP TER 1 INTRODUCTION....................................................................................................................9 2 METHODS.............................................................................................................................12 Study Area..............................................................................................................................12 Site Selection..........................................................................................................................12 Density and Occupancy Data.................................................................................................. 13 Measurement of Predictor Variables...................................................................................... 14 Statistical Analysis........................................................................................................... .......14 3 RESULTS...............................................................................................................................18 4 DISCUSSION.........................................................................................................................21 APPENDIX A ADDITIONAL TABLES.......................................................................................................25 B MODELS OF ABUNDANCE................................................................................................ 26 LIST OF REFERENCES...............................................................................................................27 BIOGRAPHICAL SKETCH.........................................................................................................31

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6 LIST OF TABLES Table page 3-1 Confusion matrix for the classi fication tree m odel for plantations.................................... 19 3-2 Models of abundance of Araucaria T it Spinetails in plantations ranked with Akaike Information Criteria........................................................................................................... 19 3-3 Differences in abundance of Araucaria Tit Spinetails by ag e of the plantation. Abundance estim ates were derived from the Poisson regression model........................... 19 A-1 Characteristics of Araucaria plantations by category of age .............................................25 A-2 Correlation between patch and la ndscape variables in plantations. ...................................25 A-3 Correlation between age and unders tory variables in plantations. ....................................25 B-1 Models of abundance of the Araucaria T it Spinetails is plan tations ranked with Akaike Inform ation Criteria...............................................................................................26

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7 LIST OF FIGURES Figure page 2-1 Location of natural forests and planta tions where surveys were conducted in the study area. ..........................................................................................................................17 3-1 Classification tree for predicting occupa ncy of Araucaria Tit Spinetails. Total classification accuracy of this tree was 81.9 %.................................................................. 20

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8 Abstract of Dissertation Pres ented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master in Science ASSESSMENT OF THE IMPORTANCE OF PLANTATIONS FOR THE ARAUCARIA TIT SPINETAIL (Leptasthenura setaria ) IN ARGENTINA By Alejandro Gerardo Pietrek May 2009 Chair: Lyn C. Branch Major: Wildlife Ecology and Conservation I assessed occupancy and density of the near threatened Araucaria Tit Spinetail ( Leptasthenura setaria ) in Araucaria forests and Araucaria plantations of Misiones, Argentina. All natural patches were occupi ed by Araucaria Tit Spinetails and only 85 % of the plantations were occupied. However, density was almost three fold higher in plantations compared to natural forests. In plantations, occupancy was best pr edicted by age and density by a model including age and isolation. A more detailed analysis showed lower densities in plantations < 10 years old compared to older plantations. Overall, my result s indicate that plantati ons may be good habitat for the Araucaria Tit Spinetail. Restoration of natural remnants and conservation of old, connected plantations in Argentina may assure the protection of si gnificant populations of spinetails and other bird species associated with Araucaria

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9 CHAPTER 1 INTRODUCTION Habitat loss and fragm entation are consid ered major threats for conservation of biodiversity. Most of the Earths surface (83 %) has been transf ormed by human activities in the last century (Sanderson et al. 2002 ), leading to substantial popul ation declines in species and sometimes to extinction. In particular, deforestat ion is a globally signif icant concern, as almost half of the terrestrial plants a nd animal species live in forests (Brockerhoff et al 2008). Habitat restoration has been proposed as one of many measures to remedy loss of the forest cover (Chazdon et al. 2008), but this prac tice is poorly developed in th ird world countries where costs may be prohibitive and conservati on efforts are oriented toward pr otection of remnant forests. Although deforestation is still high, the rate of forest loss declined from 2000 to 2005 worldwide (FAO 2007) mostly because of an increase in the area of plantation forests, leading to the question of how suitable are plantations as potentia l habitat for indigenous species. Work with birds has demonstrated that plantations ge nerally have lower species richness and diversity compared to native forests (Lindenmayer and Hobbs 2004, Barlow et al 2007, Bus de Warnaffe and Desconchat 2008). Struct ural complexity of native forest may increase the diversity of habitats, shelter and food availabil ity and has been cited recurrentl y as the main factor affecting bird diversity (Clout and Gaze 1984, Duran a nd Kattan 2005, Barlow et al. 2007). However, recent studies suggest that stand age, manageme nt practices, and the surrounding landscape may influence the biodiversity value of plantati ons (Loyn et al 2007, Luck and Korodaj 2008, Brockerhoff et al. 2008). Compared to other agri cultural matrixes, plantations might provide not only surrogate habitat for many species (Brockerhoff et al. 2003; Barbaro et al. 2005; Carnus et al. 2006), but increase connectiv ity between remnant forests (Hampson and Peterken 1998, Norton 1998) and buffer edge effects (Renjifo 2001, Fischer et al 2006).

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10 Commercial plantations are intrinsically fr agmented and transient habitat. Studies on habitat loss and fragmentation in other ecologica l systems have shown that habitat variables at the patch and landscape scales influence distribu tion of species. Patch size, patch shape, and habitat quality are important determinants of regional persistence in fragmented landscapes (Offerman et al. 1995, Turner 1996, Laurance et al. 2002, Debinski and Holt 2003, Parker et al. 2005, Schooley and Branch 2007). At a landscape leve l, habitat loss increases isolation through a reduction in amount of available habitat in the landscape and cha nges in habitat configuration and, consequently, affects dispersal. Dispersal among patches influences population viability and is a critical process for main tenance of metapopulations (Hansk i 2004). Most studies of habitat fragmentation have been conducte d in remaining natural habitat. However, the often simplified nature of plantation ecosystems facilitates te sting hypotheses and increases the inference of studies at patch and landscape scales. Variables like stand size, age and density, as well as isolation, are easily and accurately quantifiable in these landscapes generated by human activity. The Atlantic Forest of S outh America is among the most diverse and threatened ecosystems of the world. This forest, which en compassed coastal rainforests to semideciduous forests of the interior, orig inally covered around 1.5 million km2 in Brazil, eastern Paraguay and northeastern Argentina. One of the endangered forest types with in the southern part of the Atlantic Forest is Parana Pine forest also known as Araucaria ( Araucaria angustifolia ) forest. The Araucaria tree, which dominates this forest, is a critically enda ngered species (IUCN 2006) that occurs in temperate areas from 600 to 1,200 m in Southeastern Brazil and in the east of Misiones Province, Argentina. Loss of these forests has led to severe declines in fauna associated with Araucaria forest, but these declines ha ve not been well documented. In Argentina, plantations of Araucaria angustifolia have been established since the early 1950s and at present,

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11 they cover an area at least 15 times larger than natural Araucaria forest s. Declines of some species that inhabit Araucaria fo rest may have been buffered by Araucaria plantations. However, the lack of an adequate timber market and the slow growth rate of th ese trees is leading to replacement of these plantations with Loblolly pine ( Pinus taeda ). Araucaria plantations comprised around 40,000 ha in 2001. Recent estimates indicate this area has decreased by more than one half, highlighting the n eed to determine the value of Ar aucaria plantations for native species. The Araucaria Tit Spinetail ( Leptasthenura setaria) is an insectivorous passerine bird that exclusively inhabits the canopy of Araucaria forests. This species has been recorded in Araucaria plantations in recent years, expanding its known distribution in Ar gentina (Krauckzuk 2001, Cabanne 2007). Although plantations are highly fragmented, they constitute most of the remaining habitat for the species. At least three other species of birds are associated with the Araucaria forest ( Amazona pretrei, Amazona vinacea, Cyanocorax Caeruleus ) but these species already are so scarce that only anecdotal sightings can be collec ted. The goals of this study were to: 1) compare the occupancy and density of Arau caria Tit Spinetails in natural remnants and plantations and 2) model density and occupancy of the Araucaria Ti t Spinetails with respect to habitat variables in plantations and the surround ing landscape. By identif ying habitat variables related to distribution and density of spinetails, this st udy provides a scientific basis for managing current Araucaria stands and assess ing the potential impacts of their loss and replacement by introduced pines.

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12 CHAPTER 2 METHODS Study Area My research was conducted in a study area of about 30,000 km2 in the province of Misiones in northeastern Argentina (Fig. 2-1). This area has an E-W altitudinal gradient ranging from the Araucaria montane forest (900 m) to lowland broadleaf forests (150 m) and encompasses the range of forest of Araucaria angustifolia and plantations in Argentina. Natural remnants comprise approximately 19 stands highly connected by an agroforestry matrix and isolated Araucaria trees, with numerous small st ands outside protected areas and some larger stands occurring in protected ar eas (Rau 2005). Density of Araucar ia trees in forest remnants averages about 6 individual ha-1 (Rau 2005, Ros 2006). Plantations are scattered among natural remnants and also occur outside the natural range of Araucaria in northwest Misiones. Density of trees in plantations ranges from 150 to 1500 individuals ha-1 depending mostly on management and age of the plantation. Most of the plantations have been managed to produce timber on rotations of 25-30 years. Silvicultu ral practices include pruning and thinning. Site Selection The location s of natural remnants were obt ained from a recent assessment conducted by Rau (2005) and all remnants were surveyed (N=1 9, Fig. 2-1). Locations of Araucaria plantations were mapped from digital aerial photographs (1:30.000, 2007). Sixty two plantations between 1 and 435 ha in size and between 4 and 60 years ol d were selected randomly to encompass the wide array of sizes, ages and isolation of plantations. Plantations were considered different patches if distances between them were larger than 0.8 km, which is the median dispersal distance of several passerines similar in size to the Araucaria Tit Spinetail (Deon 2002).

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13 Density and Occupancy Data I assessed density and occupancy of the Arauca ria Tit sp inetail in plantations and natural forests using point counts and playbacks. Points were separated by at least 250 m. If the area of the plantation was between 1 and 5 ha, one point was located at the approximate center of the patch. I randomly selected other two additional points if the patch was large enough to meet the criteria for separation of points. If the plantati on was larger than 5 ha., I systematically placed transects (1000-m length) located at least 250 m from each other and 50 m from the edge of the patch. I selected three random poi nts for point counts and playback in each transect up to a maximum of nine points per plantation (N of point counts=150). Because natural remnants were not always discrete patches and the density of Araucaria trees was low, in remnants I followed the sampling criteria established for large planta tions, but point counts (N= 45) were made at the closest Araucaria tree to the randomly selected point. Araucaria Tit spinetails are highly mobile a nd are easily detected by their characteristic vocalizations in the top of Arau caria trees. Therefore, density of spinetails was assessed with point count surveys of 5-minutes duration using a snapshot approach in which the observer attempts to record the locations of detected bird s at a snapshot moment, with time spent before this moment identifying and locating birds and afterwards confirming locations (Buckland 2006). Distances to birds from each point were recorded with a rangefinder. Surveys were conducted from September 2007 to January 2008 betw een 700-1100 h and 1500-1800 h on non-rainy and non-windy days. After point counts were obtained, occupanc y was assessed at the same points with 5 minutes of playback. Given that detectability of the species using playback was 98.4 % in a pilot study, once the species was detecte d, no further surveys of that s ite were conducted. Birds were

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14 considered to be absent if no birds were detected after three surveys of the point, each separated by at least 8 hours. Measurement of Predictor Variables I m easured predictor variables for analyzing fa ctors affecting species distribution at patch and landscape scales in plantations. Because of the small number of remnants and high occupancy (100%), factors that affect occupancy and density of remnants were not assessed. At the patch scale I included measures of plantati on area, stand age, a nd understory height and density. Understory height and density were reco rded at a randomly placed point within a 10-m radius of the location of point counts by record ing the number of vegetation contacts on a 20-mm diameter pole marked in 10-cm increments. Unders tory measurements were taken at one point in small plantations (1-5 ha) and three points in la rge plantations (>5 ha). Stand age was determined based on records from timber companies and landow ners, and I generated a categorical variable of four levels of plantation age: 1) 4-9 years old, 2) 10-15 years old 3) 16-25 years old, and 4) more than 25 years old (Table A-1). For landscape scale analysis, I used three different measures of isolation for each plantation that served as a focal patch: i) di stance to the nearest plantation (NN), ii) mean distance to the 3 nearest plantations (THREE), an d iii) amount of available habitat (hectares of Araucaria plantations) surrounding each focal patc h, calculated by establishing a buffer of 5 km around the plantation (BUFFER). Becau se birds were not surveyed in all plantations, I did not distinguish between occupied and unoccupied patches in isolati on metrics. Plantation area and landscape variables were cal culated using ARCGIS 9.2. Statistical Analysis I used a classification tree to m odel occ upancy in plantations with DTREG (Sherrod 2003). This modeling procedure invo lves recursively partitioning of a data set into increasingly

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15 homogeneous subsets (nodes), with each split de fined based on the value of a single predictor variable (Breiman et al. 1984, Death and Fabricius 2000). At each split, each predictor variable entered into the model is assessed independently and the variable that generates the greatest improvement in homogeneity of the two resultin g nodes is selected as for splitting the node. Then the value for this variable that minimizes heterogeneity in the daughter nodes is used as a threshold value for segregating the data. This method is especially appropriate for complex datasets that include imbalance and nonlinear re lationships. I included age and size as potential predictor at the patch level in the model building. I ran three simple classification trees each with these two predictors and a different isolation me tric. Because some of my landscapes units were spatially clustered, I also adde d geographical location (x, y geogr aphic coordinates) as another variable to assess potential effect s of spatial location of samples. I used a Gini goodness of fit measure to determine optimal split and a minimum node size of 10 observations was required to perform a split and avoid over-fitting. Trees were constrained to the number of nodes allowed for one standard error from the minimum relative validation error (cross validation erro r cost relative to a one-node tree), which was calculated using v-fold cross validation. Model adequacy wa s assessed in two ways based in the percentage of data that were correctly classified and, because classification accuracy is se nsitive to the relative frequency of occupied patches, the models also were a ssessed using Cohens Kappa (K) statistic. Kappa adjusts for bias associated with random mode l agreement by measuring the actual agreement minus the agreement expected by chance, given th e frequency distribution within the data set (Cohen 1960, Fielding and Bell 1997).V alues of K can be used to classify model agreement as poor (K 0.4), good (0.4 K 0.75), or excellent (K 0.75, Landis and Koch 1977).

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16 Estimates of absolute densities of spinetails in forest remnants and plantations that ranged from 10 to 60 years were obtained with DISTANCE 5.0. Plantations of this age were analyzed because I wanted to match structure of plantation s to natural remnants. No natural remnants were comprised of young trees. I detected the species only in 16 of 45 point counts in forest remnants. Therefore, I modeled a global de tectability function for both plan tations and natural remnants and ranked the models following Akaike Informa tion criteria. Encounter rate, rather than detection probability, was the main source of vari ation in both forest remnants and plantations supporting the use of a global detect ability function for the different types of habitat. The density of birds in plantations was modeled with respect to habitat variables usin g a Poisson generalized linear mixed model where two patc h variables (stand age and plan tation size) and one landscape variable (isolation) were fixed factors and the id entity of the plantation was a random effect. For this analysis I used PROC GLIMMIX in SAS 9. 2 (SAS Institute Inc.), which allows one to obtain true log likelihood estim ates. Among the fixed factors onl y the nearest neighbor metrics and the amount of available habitat in the bu ffer (BUFFER) were correlated (Table A-2). Understory height and density were positively correlated with stand age (r>0.58) and with each other (r=0.86; Table A-3) and, therefore, both understory variables were excluded from the models. I ran a total of 15 mode ls (Table B-1). Models were ranked following the Akaike Information Criteria. To assess the potential e ffects of spatial location among samples, I added geographical location (x, y geogra phic coordinates) as another va riable and compared the best ranked model with and w ithout this variable.

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17 Figure 2-1. Location of natural forests and plan tations where surveys were conducted in the study area.

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18 CHAPTER 3 RESULTS Although all natural patches were occupied by Araucaria Spinetails, only 85% of the plantations were occupied. The final classification tree showed two term inal nodes after pruning and age was the only predictor variable (Fig 3-1). Plantations younger th an ten years old had lower occupancy rates. This model showed 81.9% agreement with the data (Table 3-1) and the Kappa statistic (K=0.49, SE= 0.12) indicated a good model agreement with the data. classification accuracy of this tree was 81.9 %. Densities were almost three times higher in pl antations than in natural remnants [density (CV %), 95 % CI Plantations, 0.94 ind. ha-1 (14 %), 071-1.23; Natural forest 0.36 ind. ha-1 (29 %), 0.20-0.64]. The model that best fit the data was a hazard ra te function with a polynomial series adjustment (Kolgomrov-Smirnov GOF p=0 .37). Abundance of spinetails in plantations was best predicted by age which had an overall wei ght of 0.99. I ran a Tukey test of least squares means to compare abundances with respect to ag e. Young plantations (4-9 years) showed lower abundances and were different from all the other categories of age (10 and greater) (ind. ha-1 49 years, 0.15; 10-15 years, 0.74; 16-25 years 1.08; >25 years, 0.88) ( (Table 3-3). A model with age and the nearest neighbor metrics ranked firs t, followed by a model considering age and the amount of available habitat in a buffer (Table 32). These two isolation metrics were the most correlated (Table A-2). Models considering isola tion as the only predicto r variable ranked poorly ( AIC>17). Incorporation of geographic loca tion did not improve the best model.

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19 Table 3-1. Confusion matrix for the cla ssification tree model for plantations. Predicted category Occupied Unoccupied Actual category Misclassified Occupied 41 1019.60% Unoccupied 1 811.10% Table 3-2 Models of abundance of Araucaria Tit Spinetails in plantations ranked with Akaike Information Criteria. Modeloa k AICc AICc wi AGE+NN 3 297.07 0 0.344 AGE+BUFFER 3 298.04 0.97 0.211 AGE 2 298.78 1.71 0.146 aModels with i 2 are presented. K = no. explanatory variables plus 1, i = AICci minimum AICc, and wi are Akaike weights. Table 3-3. Differences in abundance of Araucaria T it Spinetails by age of the plantation. Abundance estimates were derived fr om the Poisson regression model Age comparison Estimate Standard error DF t value Adj. p 4-9 y vs. 10-15 y -1.41 0.52 131.0 -2.72 0.048 4-9 y vs. 16-25 y -2.04 0.51 131.0 -4.00 0.001 4-9 y vs. >25 y -1.8 0.45 131.0 -3.97 0.002 10-15 y vs. 16-25 y -0.62 0.42 52.8 -1.48 0.46 10-15 y vs. >25 y -0.38 0.34 52.7 -1.10 0.69 16-25 y vs. >25 y 0.24 0.33 28.8 0.73 0.89

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20 Figure 3-1. Classification tree for predicting occupanc y of Araucaria Tit Spinetails. Total classification accuracy of this tree was 81.9 %.

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21 CHAPTER 4 DISCUSSION Previous res earch has indicated that natura l habitats generally are better than human generated landscapes for wildlife (Lindenmay er and Hobbs 2004, Barlow et al. 2007, Bus de Warnaffe and Desconchat 2008). Although spinetails occupied 100 % of the remnants, density was three fold higher in plantations. High densities do not ne cessarily indicate high habitat quality (Van Horne 1983, Battin 2004) and habitat quality should be evaluated in terms of spinetail productivity. However, two other studies (Krauckzuk 2001 and Cabanne et al. 2007) report a ubiquitous presence of th e species and high densities in plantations outside the natural range of Araucaria Plantations may be good habitat for th is species as suggested for several other threatened species (Kleinpaste 1990, Brockerhoff et al. 2005, Barbaro et al. 2008). The reason for higher spinetail dens ity in plantations compared to natural forests is unknown. Differences in tree density may be one factor that explains differences between density estimates in these habitats. Densities of Araucaria trees in natural remnants generally are two orders of magnitude lower than densities in plantations, which can reach 500 ind. ha-1. Degradation of Araucaria forests through selectiv e logging has decreased densities of trees in natural remnants. In the 1940s, densities of 48 trees ha-1 were recorded in some of the locations surveyed in this study (Ragonesse 1946). By the 1960s, average density was estimated at only 12 trees ha-1 (Rau 2005), but still far above the highest densities found in natural ar eas by the 1980s (7 trees ha-1 Gartland 1984, Ros 2006). The higher occupancy in natural forests than plantations may be rela ted to a high degree of connectivity in natural forests. Many of the remnants were located less than 5 km from the closest remnant, with an intervening matrix th at included plantations and isolated Araucaria trees. My observations in natural forests suggest that spinetails are present even at low densities

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22 of Araucaria in modified areas where the Araucaria is the only tree species remaining. I recorded these birds flying between trees separa ted by distances of 81 m. Joenck (2005) also reported flights of 84 m between Araucaria trees in modified ar eas. This observations suggests the spinetails might be able to move among the canopies of relatively isolated individuals. Age influences occupancy of spinetails in pl antations, and birds were mostly absent in stands less than 10 years old. These plantations generally are unoccupied even at distances less than 50 m from mature occupied plantations, indicating the spineta ils do not usually use plantations less than 10 years old. Th is result is consistent with other studies that show that older plantations exhibit higher divers ity and abundance of birds thr ough enhanced habitat structure (Luck and Korodaj 2008, Brockerhoff et al. 2008). Recent studies in natural forests also indicate that invertebrate fauna is mo re diverse and abundant in larg er trees, resulting in higher abundance of insectivorous birds (Berg et al 1994, Daz et al. 2005, Daz in prep.). The only described nests of the Araucaria Tit Spinetail have been found at 20 and 25 m height in the top of Araucaria trees (Bon 1993). Larg er trees may provide these bi rds a safe refuge against predators. Old trees dominate in natural stands which might be another reason explaining the presence of spinetails in all remnants. Planta tion area did not affect o ccupancy or density of spinetails. Range size in a related species in the s outhern temperate forest of Chile is estimated to be about 1 ha. /pair (Daz et al. 2006). If area requirements are sim ilar for Araucaria Tit Spinetails, this could promote pe rsistence of this species in small remnants and plantations. Isolation was not an important factor pred icting occupancy. Models of abundance that included only isolation were ranked very low. A model with only age as a predictor was competitive with the highest ranked models that included isolation metrics (i.e, AIC < 2). The large number and close proximity of plantations li kely facilitated colonization of this species

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23 beyond its natural distribution. A closely related species, Leptasthenura fuliginiceps, displays seasonal movements in winter from the highlands to the lowlands of we stern Argentina (Narosky and Yzurieta 2003), suggesting th at at least this species can make long distance movements when there is appropriate habita t. Surrounding habitat has been shown to play an important role in patch isolation. Land uses ar e similar across the area I surveyed in NE Argentina, and plantations and secondary forest are still important components of the landscape. In contrast, in Brazil small Araucaria patches are embedded in a hostile soy crop matrix and patches often are unoccupied even when potential source areas are as near as 700 m (Pietrek and Debarba in prep). Occupancy of plantations was high in this st udy compared with previous estimates of 50 % occupancy in twenty plantations in the same study area (Cabanne et al 2007). I found these twenty plantations to be occupied. These di fferences are unlikely to reflect changes in occupancy, but rather the previ ous study relied on passive obse rvations, which may result in lower detectability than playb ack which results in a detectab ility closer to 100 %. Although occupancy estimates from this study were high, because of the rapi d loss of Araucaria plantations, distribution maps derived from thes e estimates may overestimate the area occupied by the species in the future. Furthermore as remaining plantations become more isolated, demographic rescue and recolonization are likely to decline, resulting in an increase in unoccupied habitat. Distribution of the Araucaria Tit spinetails in Argentina is strongly associated with Araucaria plantations. Plantations not only encomp ass nearly 90 % of the remaining habitat but also exhibit high occupancy rates, though lower than natural forests, and high densities. Most of the remaining natural stands ar e old and natural regeneration is low in many of these areas threatening the viability of natural Araucaria tr ee populations (Rau 2005). Restoration of these

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24 forests and conservation of old, c onnected plantations in Argentina may assure the protection of significant populations of spinetails a nd other bird species associated with Araucaria Araucaria trees not only provide a higher quality timber than pi ne and have an intrinsi c biodiversity value, but also this species has a cultural value not fully appreciated. Araucaria seeds traditionally have been a key resource for aboriginal communities and are still harvested by local people in natural stands. The Araucaria tree increasingly has been in corporated as a flagship species in cities across its distribution. Araucaria forests and plantations in Argentina provide opportunity for community-based management in rural areas and for commercially oriented entrepreneurs to strengthen economic growth in an environmentally friendly manner while conserving the last of this forest.

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25 APPENDIX A ADDITIONAL TABLES Table A-1. Characteris tics of Araucaria plantations by category of age Age 4-9 years 10-15 years 16-25 years >25 years Mean tree height (SE) 8.8 ( 1.7) 11.9 (2.6) 16.3 (2.6) 20.5 (2.4) Density (trees/ha) 800-1500 450-800 300-450 150-250 Table A-2. Correlation between patch and lands cape variables in plantations. AREA AGE NN BUFFER THREE AREA 1 AGE 0.3282021 NN 0.0432860.054341 1 BUFFER 0.0993 0.048118 -0.51403 1 THREE -0.08825 0.110088 0.033594-0.23912 1 Table A-3. Correlation between age and understory variables in plantations. Age Understory density Understory height Age 1 Understory density 0.51 1 Understory height 0.59 0.86 1

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26 APPENDIX B MODELS OF ABUNDANCE Table B-1. Models of abundance of the Araucari a Tit Spinetails is pl antations ranked with Akaike Inform ation Criteria. Modelo k AICc AICc wi AGE+NN 3 297.07 0.00 0.34 AGE+BUFFER 3 298.04 0.97 0.21 AGE 2 298.78 1.71 0.15 AGE+SIZE+NN 4 299.33 2.26 0.11 AGE+SIZE+BUFFER 4 300.24 3.17 0.07 AGE+THREE 3 300.91 3.84 0.05 AGE+SIZE 3 300.97 3.90 0.05 AGE+SIZE+THREE 4 303.13 6.06 0.02 NN 2 314.18 17.11 0.00 BUFFER 2 315.23 18.16 0.00 SIZE 2 315.90 18.83 0.00 SIZE+NN 3 316.12 19.05 0.00 THREE 2 316.25 19.18 0.00 SIZE+BUFFER 3 317.49 20.42 0.00 SIZE+THREE 3 318.19 21.12 0.00

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27 LIST OF REFERENCES Barbaro L, Pontcharrau d L, Vetillard F, Guyon D, Jactel H (2005) Comparative responses of bird, carabid, and spider assemblages to st and and landscape diversity in maritime pine plantation forests. Ecoscience 12:110. Barbaro L, Couzi L, Bretagnolle V, Nezan J, Ve tillard F (2008) Landscape complementation for breeding and foraging in the declining Eurasian hoopoe ( Upupa epops ). Biodiversity and Conservation 17:925-935. Barlow J, Mestre LAM, Gardner TA, Peres CA (2007) The value of primary, secondary and plantation forests for Amazonian bird s. Biological Cons ervation 136:212-231. Berg A, Ehnstrom B, Gustaffson L, Hallingback T, Jonsell M, Weslien J (1994) Threatened plant, animal and fungus species in Swedish fo rests: Distribution and habitat associations. Conservation Biology 8:718-731. Bon R (1993). Observaes sobre o ninho de Leptasthenura setaria (Temminck, 1824) no Brasil. In: Primera reunin de ornitologa de la Cuenca del Plata. Asociacin Ornitolgica del Plata, Puerto Iguaz, Argentina, Se ptiembre 1993. Administracin de Parques Nacionales de Argentina y Sociedad de Biologa del Paraguay, p 7. Breiman, L, Friedman JH, Olshen RA, Stone C J (1984) Classification and regression trees. Wadsworth, Belmont, California, USA. Brockerhoff EG, Herve J, Parrotta JA, Quin e CP, Sayer J (2008) Plantation forests and biodiversity: oxymoron or opportunity? Biodiversity and Conservation 17:925-951. Brockerhoff EG, Berndt LA, Jactel H (2005) Role of exotic pine forests in the conservation of the critically endangered ground beetle Holcaspis brevicula (Coleoptera: Carabidae). N Z J Ecol 29:37. Buckland ST (2006) Point-transect surveys for songbirds: Robust methodologies. The Auk 123:345-357. Burnham KP, Anderson DR (2002) Model selec tion and multimodel inference: a practical information-theoretic approach. 2nd Edition. Springer-Verlag, New York. Cabanne GS, Zurita GA, Seipke SG, Bellocq MI (2007) Range e xpansion,density and conservation of the Araucaria Tit-Spinetail Leptasthenura setaria (Furnariidae) in Argentina: the role of the araucaria Araucaria angustifolia (Araucariaceae) plantations. Bird Conservation International 17:341-349. Carnus JM, Parrotta J, Brockerhoff EG, Arbez M, Jactel H, Kremer A, Lamb D, OHara K, Walters B (2006) Planted forests and biodi versity. Journal of Forestry 104(2):65. Chazdon RL (2008) Beyond deforestation: Rest oring forests and Ecosystem services on degraded lands. Science 320:1458.

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28 Clout MN, Gaze PD (1984) Effects of plantation forestry on birds in New Zealand. J Applied Ecology 21:795. Cohen J (1960) A coefficient of agreement fo r nominal scales.Educational and Psychological Measurement 20:37. Cozzo D (1960) Ubicacin y riqueza de los bosques espontneos de "pino" Paran (Araucaria angustifolia) existentes en la Argentina. Re vista Forestal Argentin a. T. IV(2): 46-55. Death G, Fabricius KE (2000) Classificati on and regression trees: a powerful yet simple technique for analysisof complex ecological data. Ecology 81:3178. D'Eon RG, Glenn SM, Parfitt I, Fortin MJ (2002) Landscape connectivity as a function of scale and organism vagility in a real forested landscape. Conservation Ecology 6(2): 10. Daz I, Armesto JJ, Sharon R, Sieving KE, W illson MF (2005) Linking forest structure and composition: avian diversity in succesional forests of Chiloe island, Chile. Biological Conservation 123:91-101. Daz I, Armesto JJ,Willson MF (2006) Mating success of the endemic Des Murs' Wiretail (Sylviorthorhynchus desmursii, Furnariidae) in fragmented Chilean rainforests. Austral Ecology 31:13-21. Debinski DM, Holt RD (2003) A survey and overv iew of habitat fragmentation experiments. Conservation Biology 14:342-355. Du Bus de Warnaffe G, Deconchat M (2008) Impact of four silvicultural systems on birds in the BelgianArdenne: implications for plantati on management. Biodiversity and Conservation 17:1041-1055. Dunn RR, (2004) Recovery of faunal commun ities during tropical forest regeneration. Conservation Biology 18:302. Duran SM, Kattan GH (2005) A test of the utility of exotic tree plantations for understorey birds and food resources in theColom bian Andes. Biotropica 37:129. FAO (2007) The State of the Worlds Forests. ftp.fao.org/docrep/fao/ 009. FAO, Rome, Italy. Fischer J, Lindenmayer DB, Manning AD (2006) Biodiversity, ecosystem unction, and resilience: ten guiding princi ples for commodity producti on landscapes. Frontiers in Ecology and Environment 4:80. Gartland, M (1984). Los Rodales Semilleros Nativos de Araucaria angustifolia en la provincia de Misiones. III Jo rnadas Tcnicas Bosque Implantados (Silvicultura). El Dorado, Argentina, 3-5 October 1984.

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29 Hanski I, Gaggiotti O (eds) (2004) Ecology, Genetics and Evolution of Metapopulations. Elsevier Academic Press, San Diego. Hampson AM, Peterken GF (1998) Enhancing the biodiversity of Scotlands forest resource through the development of a ne twork of forest habitats. Bi odiversity and Conservation 7:179-192. Joenck CM (2005) Utilizaao do espacio arbreo no forrageio por Leptasthenura setaria (Temminck, 1824) e Leptasthenura striolat a (Pelzen, 1856) (Furnaridaee, Aves) em floresta ombrfila mista montana no Rio Gra nde do Sul, Brasil. Dissertaao de Mestrado. Pontifcia Universidade Catlic a no Rio Grande do Sul, Brasil. Kleinpaste R (1990) Kiwis in a pine forest habitat. In: Fuller E (ed) Kiwis, a monograph of the family Apterygidae. SeTo Publishing, Auckland, pp 97. Krauczuk, ER (2001) Consideraciones sobre el Coludito de los Pinos (Leptasthenura setaria Temminck, 1824) en la Republica Ar gentina. Nuestras Aves 41:6. Landis, JR, Koch GC (1977) The measurement of observer agreement for categorical data. Biometrics 33:159. Laurance WF, Lovejoy TE Vasconcelos HL, Br una EM, Didham RK, Stouffer PC, Gascon C, Bierregaard ROJ, Laurance SG Sampaio E ( 2002). Ecosystem decay of Amazonian forest fragments: a 22-year investigation. Conservation Biology 16:605-618. Lindenmayer DB, Hobbs RJ (2004) Fauna conserva tion in Australian plantation forests-a review. Biological Conservation 119:151. Loyn RH, McNabb EG, Macak P, Noble P (2007) Eu calypt plantations as habitat for birds on previously cleared farmland in south-eastern Australia. Biological Conservation 137:533548. Luck GW & Korodaj TN (2008) Stand and lands cape-level factors relate d to bird assemblages in exotic pine plantations: Implications for forest management. Forest Ecology and Management 25:2688-2697. Mackenzie DI, Nichols JD, Royle JA Pollock KH, Bailey LA, Hines JE (2005) Occupancy modeling and estimation. Academic Press, San Diego. Narosky T, Yzurieta D (2003) Gua para la id entificacin de las aves de Argentina y Uruguay. Edicin de oro. Vzquez Mazzini Editores, Buenos Aires. Norton DA (1998) Indigenous biodiversity conservation and plantati on forestry: options for the future. New Zealand Forestry 43(2):34 Offerman, HL, Virginia HD, Pearson SM, Bi erregaard ROJ O'Neill RV (1995) Effects of forest fragmentation on neotropical fauna: current research and data availability. Environmental Reviews 3:191-211.

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30 Parker TH, BM Stansberry, Dustin Becker C, Gipson PS (2005) Edge and area effects on the ocurrence of migrant forest songbi rds. Conservation Biology 19:1157-1167. Ragonese AE, Castiglioni JA (1946) Los pinares de Araucaria angustifolia en la Repblica Argentina. Boletn de la Socied ad Argentina de Botnica 1:126-147. Rau MF (2005) Land Use and Forest Degradation in Northeastern Argentina. Dissertation, Albert-Ludwigs-University Freiburg in Breisgau. Renjifo LM (2001) Effect of natural and anthr opogenic landscape matrices on the abundance of sub-Andeanbird species. Ec ological Applications 11:14. Ros RC (2006) Caracterizacin florstica y fitoso ciolgica de la veget acin arbrea de tres unidades pedolgicas del Parque Provincial Cruce Caballero, Misione s. Dissertacao de mestrado, UFPR Curitiba. Sanderson EW, Jaiteh M, Levy MA, Redford KH Wannebo AB, Woolmer G (2002) The human footprint and the last of the wild. BioScience 52:891-904. Sherrod, PH (2003). Decision tree regression analysis so ftware (DTREG). Brentwood, Tennessee, USA. (http://www.dtreg.com). Schooley RL, Branch LC (2007) Spatial hetero geneity in habitat qua lity and cross scale interactions in metapopulations. Ecosystems 10:846-853. Van Horne, B (1983) Density as a misleading indi cator of habitat qualit y. Journal of Wildlife Management. 47: 893-901.

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31 BIOGRAPHICAL SKETCH I was born in the city of Buenos Aires in 1979 and I grew up in the surroundings of this im pressive metropolis. Since I was a child I have been deeply interested in ecological issues. I can still remember my enthusiasm when I spent my vacations in my relatives ranch in the Argentine pampas or in the mountains of centr al Argentina; I was mesmerized by natures diversity. Given my curiosity, my parents encour aged me to read about biology since an early age. As I learned more and more about ecol ogy, I witnessed the repl acement of original grasslands with crop fields in the Pampas. I saw the transformation of one of our most characteristic ecoregions. As an adolescent, I star ted to address my various inquiries not only to governmental agencies and NGOs dealing with environmental areas, but also to renowned conservation biologists in my c ountry. When I had to choose a university program, I decided to pursue undergraduate studies in Biology at the Un iversidad de Buenos Aires, from where I graduated in 2004. During my university studies I focused my attention on ecology at population scale, and at the same time I completed courses on population genetics in order to ac quire a wider view of wildlife management. Through my interaction with university professors that encouraged me to formulate my own questions, I learned the principl es of scientific reasoning and intensified my passion for research. In 2000, while I was still a student, I took part in the evaluation of the biological resources of Pampa de l Indio Provincial Park (Province of Chaco). This project was conducted by the non-governmental agency Aves Argentinas ( Argentine Birds ), a representative of Birdlife International. A year later, given my experience in this proj ect, I worked as an intern at the National Parks Administration, Northeast Regional Delega tion, where I studied i ssues concerning the System of Protected Areas of the Chaco province. In 2003, I trave lled to the Argentine

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32 Patagonia to do field work for my undergraduat e thesis. My research topic was Lizard susceptibility to predation in relation to loss of vegetation cover. During my research, I had the chance to work with Andres Novaro and Susan Walker former students of the University of Florida and zoologists of the Wildlife Conserva tion Society. This interaction allowed me to become better acquainted with the work done in the United States in my field of interest. In 2004, I received a grant from the Neotropi cal Grassland Conservancy for the project entitled Factors that predict the presence of the red winged tinamou ( Rhynchotus rufescens) in the Argentine grasslands. At that time, I obtained a second sc holarship from the Agency for Scientific Promotion and the Natio nal Institute for Agricultural Technology to participate in a project on the Integration of two non-polluting techniques for tephritidae control and for almost two years, I worked on the study of biologic control and sterile in sect technique applied to the fruit fly (Ceratitis capitata ). In 2006 I was awarded with a Fulbright Scholarsh ip to continue my studies in the US. At the University of Florida I found a program that fulfilled my expectations, and Dr. Lyn Branch, an exceptional and highly enthusiastic advisor wh o guided my first steps as a grad student. With her advice I am culminating my research that ha s focused on a threatened bird species in NE Argentina. I expect this study will be a cornerston e in my training to become an ecologist solving applied problems back home.