O jacaré-de-papo-amarelo (Caiman latirostris) é um crocodiliano de médio porte que apresenta ampla distribuição na América do Sul. O avanço das atividades antrópicas pode afetar negativamente suas populações. No entanto, a espécie aparentemente apresenta capacidade de colonizar habitats alterados em resposta à destruição dos seus habitats naturais, por isso, estudos nestes ambientes são importantes a fim de orientar futuros programas de conservação da espécie. Este estudo apresentou como objetivos verificar a estrutura populacional, uso do espaço e variação de nicho no jacaré-de-papo-amarelo em paisagem silvicultural, além de determinar fatores de discriminação isotópicos. O presente estudo foi realizado em duas fazendas de silvicultura na bacia hidrográfica do Alto Paranapanema, estado de São Paulo. Os jacarés foram capturados por meio de armadilhas e com auxílio de laço de cabo de aço. No primeiro capítulo desta tese foram investigados aspectos da estrutura populacional da espécie. No total foram capturados 16 filhotes, 28 juvenis (?: 7; ?: 21) e 8 adultos (?: 4; ?: 4). A estimativa da abundância populacional foi de 51 indivíduos (I.C. 95%: 36 - 70 indivíduos), desconsiderando os filhotes nas análises. A densidade estimada foi 2,6 indivíduos/ha (I.C. 95%: 1,8 - 3,5 indivíduos/ha) e a biomassa estimada foi de 13,3 kg/ha (I.C. 95%: 9,2 - 17,9 kg/ha). A densidade linear 11,3 indivíduos/km (I.C. 95%: 7,9 - 15,5 indivíduos/km). No segundo capítulo foram abordados aspectos ligados à área de vida e movimentação da espécie. Oito animais adultos (4 ? e 4 ?) foram monitorados por meio de radiotelemetria. A média da área de vida da espécie foi estimada segundo o mínimo polígono convexo e kernel 95% em 96,6 ± 183,9 ha e 43,2 ± 78,6 ha, respectivamente. Não houve diferença entre os sexos. O deslocamento diário médio foi 37,6 ± 18,6 m/dia. Os animais apresentaram deslocamento diário marginalmente maior durante o período reprodutivo. A matriz da paisagem mostrou permeabilidade ao deslocamento dos animais. No terceiro capítulo foram descritos os fatores de discriminação entre a dieta e tecidos do jacaré-de-papo-amarelo e possíveis diferenças entre classes etárias. As razões isotópicas de carbono e nitrogênio foram determinadas em amostras de unha e pele coletadas de 18 animais de cativeiro e em 15 amostras de sua dieta. O ?13C foi 1,2 ± 0,1? para a unha e 0,9 ± 0,2? para a pele; o ?15N foi 1,1 ± 0,1? para a unha e 0,8 ± 0,2? para a pele. Estes valores são menores que os comumente assumidos em estudos ecológicos (3-5 ?). Os resultados deste estudo enfatizam a necessidade da determinação de fatores de discriminação específicos para cada táxon, ao contrário de assumir valores médios a partir da literatura. No quarto capítulo foram abordadas possíveis variações ontogenéticas e sexuais de nicho na espécie utilizando análises isotópicas das unhas dos animais capturados. Foi identificada variação ontogenética discreta de nicho isotópico e diferença sexual somente para os juvenis. Estes resultados podem indicar uma possível exploração distinta dos recursos, com consequente redução na competição intraespecífica. / The Broad-snouted caiman (Caiman latirostris) is a medium size crocodilian widely distributed in South America. The advancement of human activities can negatively affect their populations. However, the species apparently has ability to colonize anthropic environments in response to the destruction of their natural habitat, so study these environments are important in order to guide future conservation programs for specie. This study presented as objectives verify the population structure, space use and niche variation in Broad-snouted caiman in landscape silvicultural, besides determining discrimination isotopic factors. This study was conducted in two silvicultural farms in the Alto Paranapanema watershed, São Paulo state. The caimans were captured at night with baited traps and with the aid of steel cable. In the first chapter of this thesis we investigated aspects of the population structure. In total, were captured 16 hatchlings, 28 juveniles (?: 7; ?: 21) and 8 adults (?: 4; ?: 4). The estimation of population abundance for the study area was 51 individuals (C.I. 95%: 36 - 70 individuals), excluding the hatchlings in the analyzes. The estimated density was 2.6 individuals/ha (C.I. 95%: 1.8 - 3.5 individuals/ha) and biomass was 13.3 kg/ha (C.I. 95%: 9.2 - 17.9 kg/ha). The linear density was 11.3 individuals/km (C.I. 95%: 7.9 - 15.5 individuals/km). In the second chapter, we have discussed aspects related to the home range and movement. Eight adults animals (4 ?: 4 ?) were monitored by radio telemetry. The average home range was estimated according to the minimum convex polygon and kernel 95% in 96.6 ± 183.9 ha and 43.2 ± 78.6 ha, respectively. There was no difference between the sexes. The average daily movement was 37.6 ± 18.6 m/day. The animals daily movement marginally higher during the reproductive period. The matrix showed some landscape permeability displacement of animals. In the third chapter we have described the discrimination factors between diet and tissues of Broad-snouted caiman and possible differences between age groups. The isotopic ratios of carbon and nitrogen were determined in claw and scute samples collected from 18 captive animals and in 15 samples of their diet. The ?13C was 1.2 ± 0.1 ? for claw and 0.9 ± 0.2 ? for scutes; the ?15N was 1.1 ± 0.1 ? for claw and 0.8 ± 0.2 ? for scutes. These values were much lower than the values commonly assumed in ecological studies (3-5 ?) and similar to a previous study with crocodilians. The results of this study emphasize the need to determine discrimination factors specific to taxa instead of assuming average values derived from the literature. In the fourth chapter, were addressed possible ontogenetic and sexual niche differences in species using isotope analysis of animals claws. We identified a discrete ontogenetic variation in the isotopic niche and sexual difference only for juveniles. These results may indicate differences in the exploitation of food resources and a consequent reduction in intraspecific competition.

Studies on the behavioural ecology of Przewalski horses (Equus przewalskiiy) recently reintroduced into Hustai National Park, Mongolia were carried out between 1998 and 2000. Home range size and habitat use, social, marking, and vigilance behaviour, and their reaction to flies were quantified. Home ranges of harems ranged from 129 ha to 2399 ha, with core areas of between 61 ha and 1196 ha. There was no relationship between range size and harem size, or length of time since release. The more nutritious vegetation at lower elevations was preferentially selected. The horses rested near ridges during the hotter parts of the day where there were fewer flies, and grazed in the valleys in the mornings and evenings. Woodland areas were used to shelter from the sun, despite their high fly abundance. Muscid flies were most frequently caught; Tabanids were rare. Dominance was related to age, aggression and length of time in the harem. The frequency of associative behaviours did not correlate with any social factor, but had a hygienic function. Stallions marked stud piles wid mare eliminations in different ways suggesting different functions. In addition to being vigilant for predators, the horses appeared to scan for social cues and food patches. Home range size and habitat use, and general pattern of marking and vigilance behaviour, of the wild Przewalski horses were similar to those seen among feral domestic horses, although they tended to be less aggressive than captive and feral horses. So far, the re-establishment of przewalski horses into HNP appears to have been successful, although constant monitoring of the population is necessary. As the population grows, there will be potential problems to do with exceeding the carrying capacity of the park and hybridisation with domestic horses. The future management of the horses is discussed.

Informações sobre o uso do espaço são importantes para o entendimento de processos ecológicos que envolvem uma espécie e a determinação de seu estado de conservação. Tais informações são escassas para o gênero Mazama, o mais diverso entre os cervídeos neotropicais, sendo que desenvolver metodologias para obtenção de dados ecológicos do gênero torna-se fundamental para qualquer ação de manejo envolvendo o grupo. O estudo do DNA fecal surge como uma ferramenta importante para viabilizar a coleta sistemática de informações sobre o gênero. Assim, o presente trabalho visou a estimar a área de vida e a seleção de hábitat do veado-catingueiro, comparando duas metodologias, com intuito de avaliar a aplicação do DNA fecal como alternativa para se estudar a espécie. O trabalho contou com 6 animais que tiveram suas localizações obtidas a cada 13 horas por colares GPS, no período de um ano. Nesse mesmo período e na mesma área, foram coletadas mensalmente amostras fecais, gerando um total de 830 amostras, cujo DNA foi extraído para identificação genética. A espécie das amostras foi determinada com o uso de um marcador mitocondrial (cit-b), e a identificação individual, com um painel de 11 microssatélites. Os valores de área de vida pelo método do MPC 95% variaram de 33 ha a 97 ha, e pelo método Kernel com 95% das localizações, variaram de 17 ha a 77 ha. Observou-se que as áreas de vida são alocadas nos diferentes habitats da região conforme o disponível (p = 0,072), porém são utilizadas internamente de forma selecionada (p=0,001). Neste nível, a espécie apresentou preferência pelos hábitats de cerrado e campo cerrado e evitou o campo (p < 0,005). Foram identificadas 670 amostras de veado-catingueiro e 15 genótipos únicos. A análise espacial das fezes também sugeriu uso desproporcional dos hábitats em relação à sua disponibilidade, sendo que a comparação direta entre os dois métodos revelou iguais distribuições no nível de espécie (p=0,178). As amostras individualizadas sugeriram um padrão de alta sobreposição de área de uso por diferentes indivíduos, mas avanços são necessários para melhor elucidar a questão. Perante os resultados observados, entende-se que há muito em se avançar na análise molecular das fezes que, realizada em larga escala, pode fornecer respostas importantes anteriormente inviáveis para espécies florestais. / Space use information is a key element to understand the ecological processes regarding a species and its conservation status. Such information is scarce for the genus Mazama, the most diverse group among Neotropical deer. The development of methods to obtain ecological data is fundamental to management actions concerning the group. The study of fecal DNA emerges as an important tool to enable systematic information collection about Mazama genus. Therefore, the present study aimed to estimate the home range and habitat selection of brown brocket deer comparing two methodologies in order to assess the application of fecal DNA as an alternative to study this species. Six animals were monitored with GPS collars and their location data was collected every 13 hours within one year time. Fecal samples were collected monthly in the same period and in the same area, generating a total of 830 samples whose DNA was extracted for genetic identification. The species identification was determined by a mitochondrial marker (cit-b) and individuals were identified applying a panel of 11 microsatellites. Home range was 33-97 h by MPC 95% and 17-77 h by Kernel 95%. Home rages are allocated in different habitats as available in the region (p = 0.072), but its use is internally selected (p = 0.001). At this level, the species showed preference for \"cerrado\" and \"campo cerrado\" habitats and avoidance to open field areas (p < 0.005). Genetics analysis identified 670 brown brocket deer samples and 15 unique genotypes. Feces spatial analysis suggested disproportionate use of habitats in relation to their availability in the field and the direct comparison between the two methods revealed equal distributions at the species level (p = 0.178). The genotyped samples suggested an overlapping home range pattern for different individuals, but advances are needed to further elucidate the issue. There is need for improvements in feces molecular analysis and, if held on large scale, it can provide important and previously unviable answers for forest species.

The martial eagle (Polemaetus bellicosus) is a vulnerable species that is declining throughout large portions of its range. There is an urgent need to improve understanding of this species’ ecology to inform its conservation. I equipped 20 adult martial eagles with global positioning system backpack transmitters to characterize diet and space use of the species in the Maasai Mara region of Kenya. The resulting high-resolution transmitter data sets allowed for the rapid location of kills and provided a means to estimate home range size. From November 2016 to April 2018, 191 kills were identified from 206 kill location visits. Martial eagle diet comprised 26 prey species of which hares (two Lepus species, 17.3%), impala fawns (Aepyceros melampus, 13.6%) and helmeted guineafowl (Numida meleagris, 12%) were the most numerous. Sex-based differences in diet were found, with females selecting for heavier prey items (p < 0.001). The average 95% kernel density estimated home range for the duration-of-transmitter-placement (average of 372 days) was 174.5 ± 83.2 km2, a much larger estimate than previously reported. This study is the most extensive to date on martial eagle diet and spatial ecology in eastern Africa, and the first to show dietary differences between the sexes.

Effects of sublethal, cerebral irradiation on movement and home-range patterns of black-tailed jackrabbits were studied in Curlew Valley, Utah, using radio-telemetry. Irradiation of 70 captive animals indicated that the LD50(30) was between 5,556 and 6,200 roentgens. Nine wild, free-living experimentals were trapped in desert terrain, irradiated, transmittered, and released at the capture sites. Seven wild controls were treated similarly but were not irradiated. The field-irradiation dosage was 5,000 roentgens. Tracking accuracy was determined by telemetering transmitters at fixed locations. Mean hourly movement was measured within 20-30 percent error and home ranges were measured with an error of less than 22 percent. Experimentals had a mean hourly movement of 1,176,8 feet and controls 980.0 feet, significantly different at the .05 probability level. Experimentals had a bimodal activity curve with peaks at 5:00 p.m. and 3:00 to 5:00 or 6:00 a.m. Controls displayed no such pattern. Experimentals had a mean, daily home range of 66.1 acres and controls 34,1 acres, significantly different at the .05 probability level. Experimentals had a seasonal home range of 279.0 acres and controls 247.0 acres, not significantly different at the .05 probability level. A probability index showing the frequency distribution of each animal's activity within 300-foot concentric, circular bands around a geometric center of activity showed similar distributions for both groups. The greatest concentrations of activity were within the innermost band for each group but experimentals had a slightly greater scatter of points in the outermost zone. These distributions were not significantly different at the .05 probability level. Sublethal, cerebral irradiation appears to have increased activity levels of experimental animals but not changed those home-range characteristics involving the total area occupied and tenacity of site attachment. This increased activity may have resulted from inhibitory areas in the cortex which permitted greater expression of activity from the limbic system.

The first observations of Florida burrowing owls (Athene cunicularia floridana) occurred in the 19th century on historical dry prairie habitat in south central Florida. These early observations documented the ecology of burrowing owls in rural environments. Since then the vast majority of research on this subspecies has been undertaken in suburban and urban environments during the breeding period. The research undertaken on burrowing owls in suburban and urban environments includes determining natal dispersal distance, assessing female fecundity, mate fidelity, territory fidelity, date of juvenile and adult dispersal from breeding habitat, date of clutch initiation, nesting success, density of breeding pairs, causes of mortality, prey preference, and minimum annual survival of fledglings, juveniles, and adults. Very little research has been undertaken on burrowing owls in rural environments. The purpose of this thesis was to elucidate the behavior and ecology of burrowing owls in a rural environment. The topics researched in this thesis include home range in breeding habitat, dispersal distance to post-breeding habitat, location of post-breeding habitat, behavior during the breeding period, diet of rural versus urban owls, and the evaluation of three methods to trap burrowing owls. The results of this thesis indicate that, during the daytime, juvenile burrowing owls utilized habitat very close to the main and satellite burrows during the breeding period. At night juvenile owls foraged in an extensive saw palmetto patch surrounding the breeding habitat. The predominant prey of both rural and urban burrowing owls during the breeding period was insects. Dispersal of juvenile burrowing owls from breeding habitat coincided with the flooding of the breeding habitat during the rainy season.

Understanding the relationship between organisms and their environment is particularly important for the conservation and management of endangered species. The kakapo (Strigops habroptilus, Gray 1845) is a critically endangered, lek breeding, flightless nocturnal parrot endemic to New Zealand. In April 1998, a total population of fifty-six kakapo was known to survive on offshore islands. Twenty-six kakapo, thirteen males and thirteen females, were temporarily transferred to Pearl Island (518 ha), southern Stewart Island, from April 1998 to April 1999. The translocation of kakapo to Pearl Island, and subsequent breeding season, provided an ideal experimental framework to study kakapo dispersal, movement patterns, home range development, habitat selection, and lek development during the non-breeding and breeding seasons. A total of 4425 radio locations were analysed for all twenty-six birds, with a mean error polygon of 0.03 ha and an estimated average radio telemetry error of 21.6 m. Various home range analysis techniques were used to estimate kakapo home range size and overlap including: minimum convex polygons (MCP), modified minimum convex polygons (MMCP), harmonic mean analysis, adaptive kernel methods and cluster analysis. Estimates of kakapo home range size differed significantly depending on the method used (ANOVA, general linear model: F₁₃, ₁₀₇₆ = 63.99, p < 0.0001) and the season (F₂, ₁₀₇₆ = 160.75, p < 0.0001). Breeding home range size was significantly larger than non-breeding range size (mean difference = 67.6 ha, t₂₅ = 15.27, p < 0.0001). Calculations from 100% MCP and 95% harmonic mean analysis resulted in larger estimates of home range size and overlap compared to other methods. Cluster and kernel analyses appeared to give the most accurate home range representation for kakapo. Core home range areas showed a greater degree of similarity between methods. Male and female mean annual home range size did not differ significantly, whereas males had significantly (p < 0.05) larger home ranges than females during the nonbreeding season. Minimum convex polygons and harmonic mean analysis suggested that there was no significant difference in the way in which males and females interacted with each other. Kernel and cluster analyses indicated that females would overlap a greater proportion of another bird�s home range than males would. Cluster analysis also indicated that a female would have more of her home range occupied by another bird than a male would. The fact that different methods produced different quantitative results is an important consideration when using home range analysis to make conservation management decisions. Researchers must determine which method is the most appropriate for a particular research objective, species, or study area. The application of geographical information systems, ERDAS image classification techniques and global positioning systems was an integral part of this study. A large-scale vegetation classification map of Pearl Island was produced in order to quantify habitat selection by kakapo. The unsupervised classification technique produced the least accurate vegetation map, with an accuracy measure of 17-23%, compared to 52% for the supervised classification. The highest accuracy was obtained using an integrated approach involving inductive classification and deductive mapping, resulting in a vegetation classification map which correctly classified 95% of vegetation samples. Thirty-seven ecotone classes were identified and a total ecotone length of approximately 124 km was detected. Resource selection ratios and resource selection functions were estimated using a combination of discrete, continuous and area-based habitat variables. Circular buffers around used and available point locations were generated to determine whether kakapo selectively use vegetation mosaics. The probability of selection increased with increasing species diversity in each 75-metre radius buffer. Kakapo selected habitat mosaics and vegetation types with higher species diversity and moderate to high abundance of mature rimu and yellow silver pine trees.

Understanding the ways in which animals utilize space and obtain food are central themes in modern ecology. Formulating broad principles and elucidating the factors explaining such patterns are limited, however, by the availability of data from a broad range of species and systems. This problem especially true of snakes, a predator group about which even the most basic natural history data are often entirely lacking, even among abundant, widespread, and ecologically-important species. I studied the natural history and ecosystem role of one such species, the fer-de-lance (Bothrops asper) in lowland rainforest in Costa Rica. B. asper is a large, cryptic pitviper that is highly abundant in many Central American ecosystems and is strongly relevant to human health due to high incidence of snakebite, yet its biology under natural conditions is almost entirely undocumented. I used radiotelemetry to quantify home range, movement patterns, habitat usage, and foraging behavior. B. asper was found to have smaller home ranges and reduced movement patterns than similarly-sized temperate pitvipers, likely due to a greater reliance upon ambush foraging in patches of high prey density. Snakes also demonstrated strong selection for swamp habitat, which may reflect efforts to exploit frogs as a primary food source due to low availability of small mammals at the study site. I subsequently addressed the trophic status of this B. asper population using a supplemental-feeding experiment. In comparison to control snakes, individuals receiving supplemental food had smaller home ranges, shorter and less frequent movements, increased mass acquisition, and shifted to primarily forest rather than swamp habitat. These results support the suggestion that B. asper at the study site are strongly food-limited. Finally, I tested the hypothesis that fer-de-lance mediate local seed-predation rates by influencing habitat usage and foraging behavior of rodents. A series of behavioral experiments conflicted with many existing studies in failing to support this idea, as three rodent species demonstrated little snake avoidance, and none of likely ecological relevance. Collectively, this dissertation represents the first comprehensive field study of Bothrops asper and is among the first for any tropical snake, and suggests several avenues for future research.

This thesis aims at a better mechanistic understanding of animal communities. Therefore, an allometry- and individual-based model has been developed which was used to simulate mammal and bird communities in heterogeneous landscapes, and to to better understand their response to landscape changes (habitat loss and fragmentation). / Diese Doktorarbeit strebt ein besseres mechanistisches Verständnis von Tiergemeinschaften an. Dafür wurde ein allometrie- und individuen-basiertes Modell entwickelt und dazu benutzt, Säugetier- und Vogelgemeinschaften in heterogenen Landschaften zu simulieren, und ihre Reaktion auf Landschaftsveränderungen (Habitatverlust und -fragmentierung) besser zu verstehen.

<p>Southern Africa harbours one-third of the world&rsquo / s Testudinid species, many of which inhabit arid or semi-arid areas, but ecological information on these species is scant. I studied the habitat, morphology and ecology of Kalahari tent tortoises over 13 months in semi-arid Savanna at Benfontein farm, Northern Cape Province, South Africa. In order to allow continuous monitoring of individuals, I attached radiotransmitters to males and females, split equally between two habitats, sites E (east) and W (west), with apparent differences in vegetation structure. Results of the study were based on data obtained from 27 telemetered tortoises and 161 individuals encountered opportunistically. Female Kalahari tent tortoises were larger than males and the sex ratio did not differ from 1:1. Based on person-hours to capture tortoises, the population appeared to have a low density, with more time required to capture a juvenile (35 hours) than an adult (10-11 hours). The frequency distribution of body size ranges was indicative of recruitment. Relative age, based on annuli counts, suggested that males were younger than females, perhaps because males as the smaller sex are more predation-prone than females. Linear relationships between annuli counts and shell volume indicated that, after reaching sexual maturity, female body size increased faster in volume than did male body size, possibly because a larger volume may enhance female reproductive success. Body condition differed between sites, sexes and among seasons. The hot and dry summer may account for low summer body condition, whereas vegetation differences and size effects, respectively, may account for the low body condition of tortoises in site W and in males. Site E was sandy with grasses, particularly Schmidtia pappophoroides, being the prevalent growth form. This habitat resembled a Savanna vegetation type Schmidtia pappophoroides &ndash / Acacia erioloba described for a neighbouring reserve. Site W was stonier, dominated by shrubs, and was reminiscent of Northern Upper Karoo vegetation (NKu3). Neither site resembled Kimberley Thornveld (SVk4), the designated vegetation type of the area. Differences in substrate and grazing intensity may have contributed to site vegetation differences. Rainfall had an important influence on seasonal vegetation. Short grass abundance correlated with rainfall and annual plants sprouted after spring rain. Refuge use changed according to season and sex. Males selected denser refuges than females did, perhaps because males were smaller and more vulnerable to predation and solar heat. Tortoises selected sparse, short grass as refuges in cool months, probably to maximise basking whilst remaining in protective cover. During hot periods, mammal burrows were preferred to vegetation as refugia. The smaller males spent more time in cover than females, which may be related to predator avoidance or thermoregulation.&nbsp / Females spent more time basking than males, perhaps due to their larger size and to facilitate reproductive processes. Tortoises did not brumate, but through a combination of basking, and orientation relative to the sun in their refuges, managed to attain body temperatures that allowed small bouts of activity. Body temperature for active tortoises was similar among seasons, and was higher for more specialised active behaviours, such as feeding and socialising, than for walking. Increased activity by males in spring could relate to mating behaviour while females were more active in autumn, when they foraged more than males, perhaps due to the high cost of seasonal reproductive requirements. Males displaced further per day than did females, but home range estimates did not differ between sexes. Annual home range estimates varied substantially among individuals: 0.7&ndash / 306 ha for minimum convex polygons and 0.7&ndash / 181 ha for 95% fixed kernel estimates. The ability to&nbsp / cover large areas would assist tortoises in finding resources, e.g., food, in an area where resource distribution may be patchy. Differences among seasonal home ranges and movements probably reflect seasonal climatic change / activity areas shrinking when temperatures were extreme. In order to assess the effects of a semi-arid environment on the morphology of P. oculifer, I compared its morphology to that of its &lsquo / cool-adapted&rsquo / sister taxon Psammobates geometricus, using live and museum specimens. Both P. oculifer and P. geometricus are sexually dimorphic and differences between the two species could indicate environmental or sexual selection effects, or a combination of the two. The shorter bridge length, which allowed more leg space, and wider front feet in P. oculifer cohorts probably represent traits for manoeuvring in a sandy habitat, while wider heads in P. oculifer possibly relate to interspecific differences in diet. The flatter shell in female P. oculifer, relative to P. geometricus, may represent a trade-off between space for reproductive structures, e.g., eggs, and the need to fit into small refuges, e.g., mammal burrows. Male P. oculifer had wider shells, more space around their hind legs, and wider hind feet than P. geometricus males had, all characteristics which may assist males to fight and mate in a sandy environment.</p>