At present, the Florida Burrowing Owl is being threatened by extensive habitat development throughout their small range in the state. Unfortunately, developers are able to collapse burrowing owl burrows during the non-breeding season and flush the owls from an area. In other areas such as Arizona and British Columbia translocation is being utilized to mitigate the effects of development on burrowing owls. In March 2006, the only translocation of burrowing owls in Florida was conducted by Mosaic Phosphate Company. The purpose of this thesis was to elucidate the effects of translocation on Florida burrowing owls. Topics of research include activity budgets, insect trapping, burrowing owl diet, prey availability, and hatching success for two populations of Florida burrowing owls in Hillsborough and Polk Counties, Florida. Results of this study indicate that translocation has little effect on Florida Burrowing Owl activity budgets. There were significant differences in scanning, time spent in the burrow, and resting between the control and treatment groups (p < 0.05). Though differences in behavior were present between translocated and non-translocated study groups, there was no statistically significant difference (p < 0.025) between the pre-and post translocation study group. Results of the prey availability study indicate that while there are significantly different amounts of arthropods between study areas (p < 0.025), a threshold or satiation point may have been reached at these areas, as trapping results do not match diet results. This satiation point may have been due to cattle dung present at the burrowing owl's breeding areas, which provides a micro-habitat for many prey items. While hatching success was lower for the post translocation group compared to the pre-translocation group, hatching success also was decreased for the control group.This overall decrease indicates that translocation was not the main factor affecting the hatching success of our study groups.

No description available.

Recently, the Whip-poor-will (Caprimulgus vociferous) has become focus of considerable conservation concerns as the result of evidence indicating significant population declines throughout its breeding range (Veit and Petersen 1993). The lack of quantitative data concerning much of this species natural history has delayed recovery efforts and is a fundamental shortcoming in forming effective conservation strategies. Current surveys show Pitch Pine (Pinus rigida) / Scrub Oak (Quercus illicifolia) Barrens (PPSO) as habitat with high numbers of Whip-poor-wills relative to other forest types found throughout the northeastern United States (Cavanaugh in Cink 2002), so we focused our study in these habitats in an attempt to 1) identify habitat selection within PPSO, and 2) determine characteristics of PPSO that make it relatively high quality habitat. Our Study was conducted during the 2005 and 2006 breeding seasons at the Massachusetts Military Reservation on Cape Cod, Massachusetts, USA. We used mist nets to capture adult Whip-poor-wills and affix radio-transmitters for locating individuals during night hours, using triangulation techniques. A kernel analysis of these locations was used to estimate the home range of each individual, where structural characteristics of vegetation was measured, for use in habitat selection analyses. Prey availability was estimated using captures from light traps (Leroy Koehn design, Georgetown, KY) with UV bulbs. Light traps were run on 12 different nights in each habitat during both years of the study. We assessed diet from fecal samples collected at day roost locations used by radio-marked individuals on a daily basis. Samples were dissected under a 22x stereoscope with prey fragments identified to the family when possible. Generalized Linear Mixed Models were used to model habitat selection from structural variables of the habitat collected at used and random locations within the home range, while a compositional analysis of habitat use was also done by comparing the amount of radio-locations in each habitat type to the total amount of that habitat found within the home range. A compositional analysis was also used to test for prey selection. Data from 15 Whip-poor-wills were used in our analyses. Univariate and multivariate statistics showed that there was no difference in vegetation structure between used and random sites. Ground cover was the best predictor of habitat use identified by the GLMM, but was still inefficient for determining habitat use. However, the compositional analysis of habitat use did show a preference of pitch pine – oak forests over pitch pine – scrub oak communities. The fecal analysis showed Whip-poor-wills preferred moths over scarab beetles, and “other” prey items which consisted mainly of beetles other than scarabs, along with neuropterans. Light trap captures showed prey was distributed equally among habitats at the MMR. Although our study did not show any strong relationships between vegetation structure and habitat selection, this may not be the case in habitats of lesser quality (i.e. not PPSO). The habitat preference rank from the compositional analysis directly correlated with the amount of ground cover found in each habitat, which is supporting evidence that ground cover may be an important factor in selecting habitat. Low amounts of ground cover may allow Whip-poor-wills to detect and capture prey more easily, as well as provide open area for an easy escape route from potential predators. Land management techniques such as prescribed burning that reduce understory are recommended treatments to increase habitat quality for Whip-poor-wills.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de miniaturização em anuros pode ter implicações ecológicas como, por exemplo, a redução no tamanho da ninhada produzida pelas fêmeas, o aumento do tamanho relativo dos ovos e o desenvolvimento direto. O consequente reduzido tamanho da boca tende também a constituir um fator limitante no consumo de presas por estes pequenos anuros, tornando acessível ao consumo apenas uma gama restrita de presas diminutas. Assim, estudamos parâmetros da ecologia de uma população do anuro Brachycephalus didactylus, em uma área de Mata Atlântica no sul do Espírito Santo, objetivando ampliar o conhecimento sobre tais parâmetros que compreenderam o dimorfismo sexual, algumas características da reprodução, a dieta e a relação com a disponibilidade de atrópodos no folhiço e uso do microhabitat. A amostragem dos dados ocorreu durante um ano, nas estações seca e chuvosa. Brachycephalus didactylus possuiu dimorfismo sexual, com fêmeas sendo maiores do que os machos. O maior tamanho atingido pelas fêmeas provavelmente resulta da seleção intrassexual atuando nas fêmeas para favorecer um maior investimento na massa dos ovos, já que a espécie possui um tamanho de ninhada consideravelmente reduzido (um a dois ovos). A dieta de B. didactylus foi composta por um espectro relativamente amplo de presas (17 itens), tendo elevadas proporções de pequenas presas como Acari e Collembola. O consumo de Formicidae (formigas) foi evitado por B. didactylus, apesar de essa presa ser a mais abundante no folhiço, o que categorizou o anuro como um "especialista em não comer formigas" ("non-ant specialist", sensu Toft 1980a). O reduzido tamanho da boca nas fêmeas de B. didactylus limitou o tamanho máximo de presas passíveis de serem ingeridas pelo anuro e restringindo-o ao consumo de presas pequenas, com maiores indivíduos consumindo um número maior de presas. Por fim, B. didactylus apresentou uma utilização essencialmente horizontal do hábitat, sendo mais frequentemente encontrado sobre o folhiço no chão da mata. / The miniaturization process in anurans may have ecological implications as the clutch size reduction, increasing eggs relative sizes and direct development. The resulting reduced mouth size also tends to be a limiting factor in the prey consumption by these smaller frogs, making available only a restricted range of tiny prey. Thus, we studied some ecological parameters as the sexual dimorphism, some reproductive characters, the diet and its relationship with invertebrates availability and micro-habitat use, of a Brachycephalus didactylus anuran population in an Atlantic Rainforest area in southern state of Espírito Santo. This parameters were studied aiming to increase knowledge on these species. The data sampling occurred in 2011, in the dry and rainy seasons. Brachycephalus didactylus had sexual dimorphism, with females being larger than male ones. The larger size of females probably results from intra-sexual selection, to allow greater investment in egg mass, since the species has a considerably small clutch size (two to three eggs).The diet of B. didactylus was composed by a relatively broad spectrum of prey (17 items), with high proportions of small prey such as Acari and Collembola. The consumption of Formicidae (ants) was avoided by B. didactylus, despite this being the most abundant prey in the leaf litter. The small mouth size of the B. didactylus females limited them to the consumption of small prey, with larger individuals consuming a greater number of preys. Finally, B. didactylus presented an essentially horizontal habitat use, and is more often found in leaf litter on the forest floor.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de miniaturização em anuros pode ter implicações ecológicas como, por exemplo, a redução no tamanho da ninhada produzida pelas fêmeas, o aumento do tamanho relativo dos ovos e o desenvolvimento direto. O consequente reduzido tamanho da boca tende também a constituir um fator limitante no consumo de presas por estes pequenos anuros, tornando acessível ao consumo apenas uma gama restrita de presas diminutas. Assim, estudamos parâmetros da ecologia de uma população do anuro Brachycephalus didactylus, em uma área de Mata Atlântica no sul do Espírito Santo, objetivando ampliar o conhecimento sobre tais parâmetros que compreenderam o dimorfismo sexual, algumas características da reprodução, a dieta e a relação com a disponibilidade de atrópodos no folhiço e uso do microhabitat. A amostragem dos dados ocorreu durante um ano, nas estações seca e chuvosa. Brachycephalus didactylus possuiu dimorfismo sexual, com fêmeas sendo maiores do que os machos. O maior tamanho atingido pelas fêmeas provavelmente resulta da seleção intrassexual atuando nas fêmeas para favorecer um maior investimento na massa dos ovos, já que a espécie possui um tamanho de ninhada consideravelmente reduzido (um a dois ovos). A dieta de B. didactylus foi composta por um espectro relativamente amplo de presas (17 itens), tendo elevadas proporções de pequenas presas como Acari e Collembola. O consumo de Formicidae (formigas) foi evitado por B. didactylus, apesar de essa presa ser a mais abundante no folhiço, o que categorizou o anuro como um "especialista em não comer formigas" ("non-ant specialist", sensu Toft 1980a). O reduzido tamanho da boca nas fêmeas de B. didactylus limitou o tamanho máximo de presas passíveis de serem ingeridas pelo anuro e restringindo-o ao consumo de presas pequenas, com maiores indivíduos consumindo um número maior de presas. Por fim, B. didactylus apresentou uma utilização essencialmente horizontal do hábitat, sendo mais frequentemente encontrado sobre o folhiço no chão da mata. / The miniaturization process in anurans may have ecological implications as the clutch size reduction, increasing eggs relative sizes and direct development. The resulting reduced mouth size also tends to be a limiting factor in the prey consumption by these smaller frogs, making available only a restricted range of tiny prey. Thus, we studied some ecological parameters as the sexual dimorphism, some reproductive characters, the diet and its relationship with invertebrates availability and micro-habitat use, of a Brachycephalus didactylus anuran population in an Atlantic Rainforest area in southern state of Espírito Santo. This parameters were studied aiming to increase knowledge on these species. The data sampling occurred in 2011, in the dry and rainy seasons. Brachycephalus didactylus had sexual dimorphism, with females being larger than male ones. The larger size of females probably results from intra-sexual selection, to allow greater investment in egg mass, since the species has a considerably small clutch size (two to three eggs).The diet of B. didactylus was composed by a relatively broad spectrum of prey (17 items), with high proportions of small prey such as Acari and Collembola. The consumption of Formicidae (ants) was avoided by B. didactylus, despite this being the most abundant prey in the leaf litter. The small mouth size of the B. didactylus females limited them to the consumption of small prey, with larger individuals consuming a greater number of preys. Finally, B. didactylus presented an essentially horizontal habitat use, and is more often found in leaf litter on the forest floor.

This study attempted to explain an apparent inverse relationship between pack ice proximity and breeding success of Black Guillemots (Cepphus grylle) on Cooper Island, a barrier island in the western Beaufort Sea near Barrow, AK. I elucidated the first linear relationship between energy density and body size for the elusive Arctic Cod (Boreogadus saida). I discovered and ground-truthed the existence of previously unknown guillemot foraging habitat on small 50 m2 ice floes distant from the pack ice. I developed new daily metrics for quantifying the provisioning to linear (8 d – 18 d) and Post-Linear (19 d – fledge) chicks. I found daily consensus between Linear and Post-Linear chicks about the level of provisioning at the colony. Finally, I explained those daily changes with significant correlations with wind speed and direction. / October 2007

Post-pelagic juvenile and subadult Kemp's ridley sea turtles (Lepidochelys kempii) (20-40 cm straight carapace length) utilize nearshore waters of the northwestern Gulf of Mexico as nursery or developmental feeding grounds. This study utilizes 10 years of entanglement netting data to characterize long-term abundance and distribution of Kemp's ridley sea turtles at index habitats in this region. Netting surveys were conducted during April-October 1993-2002, primarily at Sabine Pass, Texas and Calcasieu Pass, Louisiana. Additionally, this study takes an ecosystem-based approach to understanding factors influencing Kemp's ridley in-water abundance and distribution via the development of a conceptual model incorporating data on nesting dynamics, environmental conditions, prey availability, and predation pressure. Overall monthly mean ridley catch-per-unit-effort (CPUE) peaked in the beginning of summer (April-June), probably in response to rising water temperatures and seasonal occurrence of blue crab prey. Annual mean ridley CPUE across all study areas peaked in 1994, 1997, 1999 and 2002, suggesting a 2-3 year cycle in abundance that may be related to patterns in clutch size or hatch success at the Rancho Nuevo, Mexico nesting beach. However, ridley CPUE in nearshore waters remained relatively constant or decreased slightly even as number of hatchlings released from Rancho Nuevo increased exponentially. Annual declines in Texas strandings since 1994 and subsequent increases in Florida counterparts since 1995 suggest a shift in ridley distribution from the western to eastern Gulf in recent years. Significant declines in ridley CPUE at Sabine Pass since 1997 coincided with a concurrent reduction in blue crab size, but a similar trend was not detected at Calcasieu Pass. Kemp's ridley occurrence at study sites was not significantly related to shrimping activity/by-catch. There also were no biologically significant relationships between Kemp's ridley CPUE and abiotic factors, nor were ridleys deterred from utilizing areas frequented by bull sharks. Overall, nesting dynamics and prey availability were conceptual model components appearing to have the greatest influence on nearshore ridley occurrence.

This study attempted to explain an apparent inverse relationship between pack ice proximity and breeding success of Black Guillemots (Cepphus grylle) on Cooper Island, a barrier island in the western Beaufort Sea near Barrow, AK. I elucidated the first linear relationship between energy density and body size for the elusive Arctic Cod (Boreogadus saida). I discovered and ground-truthed the existence of previously unknown guillemot foraging habitat on small 50 m2 ice floes distant from the pack ice. I developed new daily metrics for quantifying the provisioning to linear (8 d – 18 d) and Post-Linear (19 d – fledge) chicks. I found daily consensus between Linear and Post-Linear chicks about the level of provisioning at the colony. Finally, I explained those daily changes with significant correlations with wind speed and direction.

This study attempted to explain an apparent inverse relationship between pack ice proximity and breeding success of Black Guillemots (Cepphus grylle) on Cooper Island, a barrier island in the western Beaufort Sea near Barrow, AK. I elucidated the first linear relationship between energy density and body size for the elusive Arctic Cod (Boreogadus saida). I discovered and ground-truthed the existence of previously unknown guillemot foraging habitat on small 50 m2 ice floes distant from the pack ice. I developed new daily metrics for quantifying the provisioning to linear (8 d – 18 d) and Post-Linear (19 d – fledge) chicks. I found daily consensus between Linear and Post-Linear chicks about the level of provisioning at the colony. Finally, I explained those daily changes with significant correlations with wind speed and direction.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation presents information on (1) the advertisement and aggressive calls of Crossodactylus schmidti and on (2) the species diet and its relationship with prey availability. The study was conducted with populations from the Parque Estadual do Turvo, located in the northwestern region of Rio Grande do Sul, Brazil. The park has an area of 17,491.4 ha and constitutes the largest preserved remnant of Mesophytic Semideciduous Forest in the state of Rio Grande do Sul. The advertisement and aggressive calls of C. schmidti were described based on vocalizations of seven individuals recorded between October 2009 and February 2010. Compared to the advertisement calls described for other species of the genus, the advertisement call of C. schmidti differs in the temporal structure by having fewer notes per call and longer intervals between notes, and in the spectral structure by having lower values of dominant frequency. The aggressive call of C. schmidti is a variation of the advertisement call, which is similar to this in the note duration and dominant frequency values, but is a longer call, having fewer notes with longer intervals between them. The advertisement and aggressive calls of C. schmidti may be emitted separately, or the aggressive call may be followed by the advertisement call. The diet of C. schmidti was evaluated from September 2009 to March 2010, based on 93 stomach contents obtained by the technique of regurgitation (n= 80) and analysis of stomach contents of collected specimens (n= 13). In this study we determined the diet niche breadth, evaluated the relationship of diet composition with prey availability in the environment, and we also looked for ontogenetic and sexual changes and composition differences in the diet. Nineteen categories of prey were consumed, and ants, beetles and flies presented the highest importance values. Despite the varied diet, the diet niche breadth was low, with few prey categories predominantly consumed. Ants, flies and spiders were consumed in similar proportion to that estimated in the environment. There was no relationship between mouth width and length and/or volume of prey consumed, but the differences in diet composition between males and females, and between adults and juveniles, were significant. Considering the varied diet, the relationship between the most important items of diet with their availability in the environment, and the narrow niche breadth found, C. schmidti seems to be an opportunistic forager with feeding habits similar to other species of the genus. The similarities in the importance of items such as ants, beetles, flies and insect larvae in diet of C. schmidti and other species of the genus suggest a strong phylogenetic influence. / A presente dissertação apresenta informações sobre (1) o canto de anúncio e o canto agressivo de Crossodactylus schmidti, e sobre (2) a dieta da espécie e sua relação com a disponibilidade de presas. O estudo foi conduzido com populações do Parque Estadual do Turvo, localizado na região noroeste do Rio Grande do Sul, Brasil. O parque possui uma área de 17.491,4 ha e constitui o maior remanescente preservado de Floresta Estacional Semidecídua do estado do Rio Grande do Sul. Os cantos de anúncio e agressivo de C. schmidti foram descritos a partir de vocalizações de sete indivíduos gravadas entre outubro de 2009 e fevereiro de 2010. Comparado aos cantos de anúncio descritos para outras espécies do gênero, o de C. schmidti difere na estrutura temporal por apresentar menor número de notas por canto e maior intervalo entre as notas, e, na estrutura espectral, difere por apresentar menores valores de frequência dominante. O canto agressivo de C. schmidti é uma variação do canto de anúncio, sendo semelhante a este na duração das notas e nos valores de freqüência dominante, mas é um canto mais longo, possuindo menor número de notas e maior intervalo entre elas. O canto de anúncio e o canto agressivo de C. schmidti podem ser emitidos isoladamente ou pode ser emitido o canto agressivo seguido do canto de anúncio. A dieta de C. schmidti foi avaliada de setembro de 2009 a março de 2010, a partir de 93 conteúdos estomacais obtidos através da técnica de regurgitação (n= 80) e da análise dos conteúdos estomacais de espécimes coletados (n= 13). Nesse trabalho, determinamos a amplitude do nicho alimentar da espécie, avaliamos a relação da dieta com a disponibilidade de presas no ambiente e testamos as diferenças ontogenéticas e sexuais na composição da dieta. Dezenove categorias de presas foram consumidas, sendo formigas, besouros e dípteros as que apresentaram os maiores valores de importância. Apesar da dieta variada, a amplitude alimentar foi baixa, com poucas categorias de presas consumidas predominantemente. Formigas, dípteros e aranhas foram consumidas em proporção semelhante à estimada no ambiente. Não houve relação entre a largura da boca e o comprimento médio e/ou volume das presas consumidas, mas as diferenças na composição da dieta entre machos e fêmeas e entre adultos e juvenis foram significativas. Considerando a dieta variada, a relação entre os itens mais importantes da dieta com sua disponibilidade e a estreita amplitude do nicho alimentar, C. schmidti parece ser um forrageador oportunista de hábito alimentar similar aos de outras espécies do gênero. As semelhanças na importância de itens como formigas, besouros, dípteros e larvas de insetos na dieta C. schmidti e na de outras espécies do gênero sugere uma forte influência filogenética.