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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Avaliação andrológica e criopreservação de sêmen de pumas (Puma concolor Linnaeus, 1771) adultos / Andrologic evaluation and cryopreservation of adult cougar s (Puma concolor Linnaeus, 1771) semen

Souza, Thyara de Deco 02 March 2009 (has links)
Made available in DSpace on 2015-03-26T13:46:41Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2387024 bytes, checksum: 01d23ccd7bff613e81deb218403993c6 (MD5) Previous issue date: 2009-03-02 / The wild felines is one of the most endangered species of the world and its population is affected by some factors that vary geographically because of the alduteration of their habitat, food available, strong hunt pressure or even the low population density. Assisted reproduction techniques such as gamete s cryopreservation and in vitro fertilization are fundamental for the conservation as they contributes to restoring genetic vigor and makes possible to transfer genetics sources without moving the animals itself. The aim of this study is collect semen from cougar (Puma concolor), describe its physics and morphologics characteristics and also evaluate its frozen capacity using two extenders with TRIS- citrate and egg yolk were evaluated, one with 5% of glycerol and the other with 7.5%. Five captive adult cougars from Mato Grosso do Sul s Rehabilitation Center Brazil (CRAS-MS) were used. The anesthetic protocol was an association of ketamine (10 mg/kg) and xilazine (1.2 mg/kg). Semen collection was done through electroejaculation method with a maximum of four series of 10 stimuli with 16 Volts. Before with collection the urine was collected and the bladder was washed with sterile physiologic solution. The semen samples were evaluated using the following parameters: physics aspects (color and smell), volume, concentration, morphology, sperm progressive status, sperm motility. The last two parameters were used to calculate the sperm motility index. The semen samples were packed in 0.25 ml straws, cooled at a rate 0.55ºC/min during two hours (one for de cooling and one in equilibrium) and finely frozen at a rate 5.8ºC/min. The thawing was carried through immersion in water at 37ºC during 30 seconds. The post thawed samples were evaluated using the sperm progressive status, sperm motility, sperm longevity (thermorresistance test) and hiposmotic swelling tests. The protocol used in this study for captive cougar s semen collection were efficient, with the acquisition of samples free from urine and a medium of total spermatozoids per ejaculate higher than those describe in literature for this species. The sperm motility index was also higher than those describe in literature. The medium of structurally abnormal spermatozoa were 53.88% and besides the high pleiomorphic rate only one animal between those evaluated at this study was considered teratospermic. The most frequent pathologies were tightly coiled or bent tail, coiled or bent tail and tail coiled on the head. The cryopreservation and thawing protocol were good for the cryopreservation of cougar s semen. The sperm motility index reduced only after 40 minutes of incubation at 38ºC for both extenders tested (16.25% in the extender with 5% of glycerol and 11.25% in the extender with 7.5%) and a medium of 25 to 29% of the spermatozoids showed plasmatic membrane integrity. There was no difference (p>0.05) between the two concentrations of glycerol used, according to the parameters evaluated. / Os felinos silvestres estão entre as espécies mais ameaçadas do mundo, e sua população é afetada por fatores que variam geograficamente, seja a descaracterização de habitats, disponibilidade de alimentos, forte pressão de caça ou baixa densidade populacional. Tecnologias de reprodução assistida, como a criopreservação de gametas e a fertilização in vitro, são ferramentas fundamentais para a conservação das espécies, uma vez que auxiliam na manutenção de uma população geneticamente viável e permitem translocação de material genético sem a necessidade do transporte dos animais. O presente estudo objetivou coletar sêmen de pumas (Puma concolor) assim como descrever as características físicas e morfológicas do sêmen e também avaliar a congelabilidade do sêmen desta espécie empregando dois meios de congelamento a base de TRIS-citrato e gema de ovo, sendo um com 5% de glicerol e outro com 7,5%. Foram utilizados cinco pumas adultos mantidos em condições de cativeiro no Centro de Reabilitação de Animais Silvestres do estado do Mato Grosso do Sul Brasil (CRAS-MS). Os animais foram anestesiados com associação de cloridrato de quetamina e cloridrato de xilazina nas doses de 10 mg/kg e 1,2 mg/kg, respectivamente. |Posteriormente foi realizada a coleta, por meio da eletroejaculação, que consistiu na aplicação de um máximo de 4 séries de 10 estímulos elétricos de 16V. Após a sedação, procedeu-se a coleta de urina e lavagem da bexiga com solução fisiológica estéril. O sêmen coletado foi analisado quanto ao aspecto físico (cor e odor), volume, concentração e morfologia espermática, além do vigor e da motilidade, que foram utilizados para o cálculo do índice espermático. O sêmen foi envasado em palhetas de 0,25 mL, resfriado sob uma taxa de 0,55ºC/min por duas horas (uma hora de resfriamento e mais uma hora de equilíbrio) e por fim congelado a uma taxa de 5,8ºC/min. As amostras de sêmen foram descongeladas em banho maria a 37ºC por 30 segundos e avaliadas quanto ao vigor e à motilidade espermática, além dos teste de termorresistência e hiposmótico. O protocolo proposto para coleta de sêmen de puma mantidos em cativeiro mostrou-se eficiente, com a obtenção de amostras livres de contaminação com urina e com uma média total de espermatozóides por ejaculado superior à descrita na literatura para esta espécie. O índice espermático observado nas amostras frescas também foi superior ao descrito na literatura. A média de patologias totais observada foi de 53,88% e apesar da elevada taxa de espermatozóides patológicos, apenas um indivíduo dentre os pumas avaliados mostrou-se teratospérmico. As patologias mais frequentemente observadas foram cauda fortemente dobrada ou enrolada, cauda dobrada ou enrolada e cauda enrolada na cabeça. O protocolo de congelamento e descongelamento empregado mostrou-se satisfatório na criopreservação de sêmen de puma. O índice espermático declinou somente após 40 minutos de incubação a 38ºC em ambos os meios testados (16,25% no meio com 5% de glicerol e 11,25% no meio com 7,5%) e em média de 25 a 29% dos espermatozóides apresentaram integridade na membrana plasmática. Não foram observadas diferenças (p>0,05) entre os parâmetros avaliados após a criopreservação, utilizando as diferentes concentrações de glicerol no meio TRIS- gema de ovo.
22

Influência do ambiente e relações predador-presa em uma comunidade de mamíferos terrestres de médio e grande porte em Floresta Ombrófila Densa / Influence of environmental conditions and predator-prey relationship in a community of medium and large sized terrestrial mammal in dense rain forest

Alves, Maísa Ziviani 25 May 2016 (has links)
A destruição de florestas tropicais é intensa e pode levar à extinção de espécies sensíveis à fragmentação. Na Mata Atlântica, mamíferos com importantes funções no equilíbrio do ecossistema, como Panthera onca (onça-pintada), já estão ausentes em grande parte do bioma. Logo, é de extrema urgência compreender os processos que influenciam na permanência dessas espécies em uma área, para evitar futuras extinções locais. Assim, o objetivo geral deste estudo foi analisar as influências das características ambientais sobre a riqueza e ocorrência de mamíferos terrestres de médio e grande porte e as relações espaço-temporais entre o predador de topo, mesopredadores e presas em uma área de Mata Atlântica contíngua ao Parque Estadual da Serra do Mar com recente histórico de perturbação (Parque das Neblinas, Bertioga, SP). A coleta de dados foi realizada por armadilhamento fotográfico, durante 90 dias em 2013 e 2014, em 27 pontos amostrais, distantes 1 km entre si. As características ambientais avaliadas foram altitude, densidade de drenagem, precipitação média, temperatura média, número de palmitos (Euterpe edulis) e presença de trilhas naturais. Para analisar as influências do ambiente sobre a riqueza e ocorrência de espécies (com mais de três registros por ano) foram utilizados Modelos Lineares Generalizados. Para as demais análises, as espécies foram agrupadas em predador, mesopredadores, presas de grande, médio e pequeno porte. O período e sobreposição de atividade destes grupos foram estimados por meio da densidade de Kernel. A abundância foi estimada para mesopredadores e presas, através de modelos N-mixture. Para analisar a probabilidade de ocupação e detecção do predador de topo foram usados modelos de ocupação single-season. Foram amostrados 18 mamíferos terrestres de médio e grande porte, dos quais nove estão ameaçados de extinção ((Cabassous unicinctus (tatu-de-rabo-mole), Cuniculus paca (paca), Leopardus guttulus (gato-do-mato-pequeno), Leopardus pardalis (jaguatirica), Leopardus wiedii (gato-maracajá), Pecari tajacu (cateto), Puma concolor (onça-parda), Puma yagouaroundi (gato-mourisco) e Tapirus terrestris (anta)). A riqueza de espécies foi positivamente influenciada pelo maior volume de chuvas e a ocorrência da maioria das espécies (C. unicinctus, Dasypus novemcinctus (tatu-galinha), P. concolor, Sylvilagus brasiliensis (tapiti) e T. terrestris) foi influenciada pela densidade de drenagem em 2013. Em 2014, a riqueza não foi explicada por nenhuma característica e apenas quatro espécies sofreram influência de alguma característica ambiental. O predador de topo registrado foi catemeral, os mesopredadores e presas de grande porte mostraram-se mais noturnos e presas de médio e pequeno porte foram mais diurnas. Presas menores apresentaram a maior sobreposição total com o predador (Δ1=0,72). A influência sobre a probabilidade de ocupação da área pelo predador variou entre os anos, tendo sido pela abundância de presas de grande e pequeno porte, em 2013, e pela abundância de presas de médio porte, em 2014. A detecção foi influenciada apenas em 2014, de forma negativa pelas ocasiões. A partir destes resultados foi possível identificar as características ambientais que devem ser mantidas na área, como a disponibilidade de recursos hídricos e abundância de presas, a fim de conservar das espécies resilientes. / The destruction of tropical forests is alarming and may lead to the extinction of species susceptible to fragmentation. In the Atlantic Forest, mammals with important functions in the ecosystem balance, such as Panthera onca (jaguar), are already absent in part of the biome. Therefore, it is urgent to understand the processes that influence the permanence of these species in an area, in order to prevent future local extinctions. Thus, this study aimed to analyze the influence of environmental characteristics on the richness and occurrence of terrestrial mammals of medium and large size; as well as the spatio-temporal relationship between the top predator, mesopredator and preys, in the Atlantic foreste area continuos continuous with Serra do Mar State Park, with recent degradation history (Neblinas Park, Bertioga, State of São Paulo). Sample data was collected by camera trapping for 90 days in 2013 and 2014, 27 sampling points 1km distant from each other. The environmental characteristics were altitude, drainage density, average rainfall, average temperature, number of palm hearts (Euterpe edulis) and the presence of nature trails. Generalized Linear Models were used to analyze the environmental influences on the richness and occurrence of species (with more than 3 records per year). For the other analyses, species were grouped into predator, mesopredators, preys of large, medium and small size. The period and overlap activity of these groups were estimated by the Kernel density. Abundance was estimated for mesopredators and prey through N-mixture models. Single-season occupancy models were used to analyze the probability of occupancy and detection of top predators. A total of 18 terrestrial mammals of medium and large size were sampled, with nine of them being threatened with extinction: Cabassous unicinctus (naked-tailed armadillo), Cuniculus paca (paca), Leopardus guttulus (oncilla), Leopardus pardalis (ocelot), Leopardus wiedii (margay), Pecari tajacu (collared peccary), Puma concolor (cougar), Puma yagouaroundi (jaguarundi) and Tapirus terrestris (tapir). In the 2013, the species richness was positively influenced by the largest volume of precipitation and the species occurrence (C. unicinctus, Dasypus novemcinctus (tatu-galinha), P. concolor, Sylvilagus brasiliensis (tapiti) e T. terrestris) was interfered by the drainage density. In 2014, richness was not explained by any of the environmental characteristics mentioned and only four species have suffered influence of them. The top predator recorded was catemeral, the mesopredator and large prey were mainly nocturnal and prey of medium and small size were mainly daylight. Smaller prey had the highest total overlap with the predator (Δ1=0.72). The influence on the probability of occupancy of the area by the predator varied between the years: in 2013 it was the abundance of large and small preys, and in 2014, the influence was the abundance of medium preys. The detection was negatively influenced by the occasion only in 2014. Our findings showed the environmental characteristics that should be maintained in the area, such as water resources and abundance of prey, for conservation of Atlantic Forest and its fauna community.
23

Número mínimo de indivíduos e diversidade genética de onça-parda (Puma concolor) no Núcleo Santa Virgínia, Parque Estadual da Serra do Mar, São Paulo

Martins, Niara 27 May 2011 (has links)
Made available in DSpace on 2016-06-02T20:21:26Z (GMT). No. of bitstreams: 1 3758.pdf: 2809059 bytes, checksum: b38018f70b56ac8d09c7f5cf7e865731 (MD5) Previous issue date: 2011-05-27 / Financiadora de Estudos e Projetos / ABSTRACT The cougar (Puma concolor) is the second largest feline species in Brazil. It has a wide distribution across the Americas, occurring from southwestern Canada to the Strait of Magellan, in the extreme south of Argentina and Chile, throughout the Brazilian territory. In this study we estimated the minimum number of individuals and genetic diversity of cougars in the Santa Virginia Unit, Serra do Mar State Park (PESM), São Paulo, based on fecal DNA analysis. Hair snares were also used to an attempt to obtain more samples. For the diagnosis of the species, we amplified a 146bp fragment of the cytochrome b gene of mitochondrial DNA. We used six microsatellite loci for the fecal samples individualization, to estimate the minimum number of individuals and genetic characterization of the population. No hair sample was obtained during the study. Among the 40 fecal samples obtained, 34 were successfully diagnosed, and we found 25 samples of P. concolor, eight of Leopardus tigrinus and one of Leopardus pardalis. The multiloci genotypes were obtained for only 15 samples belonging to 12 different puma individuals. The allelic dropout average rate was 10.43%. The mean observed heterozygosity was 0.6202, lower than that found for the species in fragmented areas of Cerrado, in the northeastern São Paulo. There were deviations in Hardy-Weinberg equilibrium (HWE) for one locus and a deficit of heterozygous for the set loci used. However, there was no evidence of recent population bottleneck. Therefore, the deviation in HWE could be caused by the presence of null alleles or the low number of samples. Little relationship was found between individuals (6.1% Half-Sibs), indicating a possible continuous stream of cougars in the region. Thus, the PESM deserves special attention for being the largest continuous remnant of Brazilian Atlantic Forest and, therefore, similar studies are needed in the others Units of this Park so that together they can provide a more comprehensive view of the P. concolor situation in this biome. / A onça-parda (Puma concolor) é a segunda maior espécie de felino do Brasil. Possui uma ampla distribuição pelo continente americano, ocorrendo desde o sudoeste do Canadá até o Estreito de Magalhães, no extremo sul da Argentina e do Chile, passando por todo o território brasileiro. Nesse estudo foi estimado o número mínimo de indivíduos e a diversidade genética da onça-parda a partir de DNA fecal, no Núcleo Santa Virgínia, Parque Estadual da Serra do Mar (PESM), São Paulo. Armadilhas de pelos também foram utilizadas para uma mais uma tentativa na obtenção de amostras. Para o diagnóstico da espécie foi amplificado um pequeno fragmento do gene citocromo b do DNA mitocondrial. Ao todo foram utilizados seis locos de microssatélites para a individualização das amostras de fezes, estimativa do número mínimo de indivíduos e caracterização genética da população. Nenhuma amostra de pelo foi obtida durante o estudo. Dentre as 40 amostras de fezes obtidas, 34 foram diagnosticadas com sucesso, sendo encontradas 25 amostras de P. concolor, oito de Leopardus tigrinus e uma de Leopardus pardalis. Os genótipos multilocos foram obtidos para apenas 15 amostras, pertencentes a 12 indivíduos diferentes de onça-parda. A taxa média de allelic dropout foi de 10,43%. A heterozigosidade média observada foi de 0,6202, inferior a encontrada para a espécie em áreas fragmentadas do Cerrado, na região nordeste do Estado de São Paulo. Houve desvio no equilíbrio de Hardy-Weinberg (HWE) para um dos locos e déficit de heterozigotos para o conjunto de locos utilizados. Contudo, não houve evidência de gargalo populacional recente. Dessa forma, o desvio no HWE pode ter sido causado pela presença de alelos nulos ou pelo baixo número de amostras. Pouca relação foi encontrada entre os indivíduos (6,1% de HS), indicando um possível fluxo contínuo de onças-pardas na região. Sendo assim, o PESM merece especial atenção por ser o maior remanescente contínuo da Mata Atlântica brasileira e, por isso, estudos similares são necessários nos demais Núcleos desse Parque para que juntos possam fornecer uma visão mais abrangente da situação da espécie P. concolor nesse bioma.
24

Influência do ambiente e relações predador-presa em uma comunidade de mamíferos terrestres de médio e grande porte em Floresta Ombrófila Densa / Influence of environmental conditions and predator-prey relationship in a community of medium and large sized terrestrial mammal in dense rain forest

Maísa Ziviani Alves 25 May 2016 (has links)
A destruição de florestas tropicais é intensa e pode levar à extinção de espécies sensíveis à fragmentação. Na Mata Atlântica, mamíferos com importantes funções no equilíbrio do ecossistema, como Panthera onca (onça-pintada), já estão ausentes em grande parte do bioma. Logo, é de extrema urgência compreender os processos que influenciam na permanência dessas espécies em uma área, para evitar futuras extinções locais. Assim, o objetivo geral deste estudo foi analisar as influências das características ambientais sobre a riqueza e ocorrência de mamíferos terrestres de médio e grande porte e as relações espaço-temporais entre o predador de topo, mesopredadores e presas em uma área de Mata Atlântica contíngua ao Parque Estadual da Serra do Mar com recente histórico de perturbação (Parque das Neblinas, Bertioga, SP). A coleta de dados foi realizada por armadilhamento fotográfico, durante 90 dias em 2013 e 2014, em 27 pontos amostrais, distantes 1 km entre si. As características ambientais avaliadas foram altitude, densidade de drenagem, precipitação média, temperatura média, número de palmitos (Euterpe edulis) e presença de trilhas naturais. Para analisar as influências do ambiente sobre a riqueza e ocorrência de espécies (com mais de três registros por ano) foram utilizados Modelos Lineares Generalizados. Para as demais análises, as espécies foram agrupadas em predador, mesopredadores, presas de grande, médio e pequeno porte. O período e sobreposição de atividade destes grupos foram estimados por meio da densidade de Kernel. A abundância foi estimada para mesopredadores e presas, através de modelos N-mixture. Para analisar a probabilidade de ocupação e detecção do predador de topo foram usados modelos de ocupação single-season. Foram amostrados 18 mamíferos terrestres de médio e grande porte, dos quais nove estão ameaçados de extinção ((Cabassous unicinctus (tatu-de-rabo-mole), Cuniculus paca (paca), Leopardus guttulus (gato-do-mato-pequeno), Leopardus pardalis (jaguatirica), Leopardus wiedii (gato-maracajá), Pecari tajacu (cateto), Puma concolor (onça-parda), Puma yagouaroundi (gato-mourisco) e Tapirus terrestris (anta)). A riqueza de espécies foi positivamente influenciada pelo maior volume de chuvas e a ocorrência da maioria das espécies (C. unicinctus, Dasypus novemcinctus (tatu-galinha), P. concolor, Sylvilagus brasiliensis (tapiti) e T. terrestris) foi influenciada pela densidade de drenagem em 2013. Em 2014, a riqueza não foi explicada por nenhuma característica e apenas quatro espécies sofreram influência de alguma característica ambiental. O predador de topo registrado foi catemeral, os mesopredadores e presas de grande porte mostraram-se mais noturnos e presas de médio e pequeno porte foram mais diurnas. Presas menores apresentaram a maior sobreposição total com o predador (Δ1=0,72). A influência sobre a probabilidade de ocupação da área pelo predador variou entre os anos, tendo sido pela abundância de presas de grande e pequeno porte, em 2013, e pela abundância de presas de médio porte, em 2014. A detecção foi influenciada apenas em 2014, de forma negativa pelas ocasiões. A partir destes resultados foi possível identificar as características ambientais que devem ser mantidas na área, como a disponibilidade de recursos hídricos e abundância de presas, a fim de conservar das espécies resilientes. / The destruction of tropical forests is alarming and may lead to the extinction of species susceptible to fragmentation. In the Atlantic Forest, mammals with important functions in the ecosystem balance, such as Panthera onca (jaguar), are already absent in part of the biome. Therefore, it is urgent to understand the processes that influence the permanence of these species in an area, in order to prevent future local extinctions. Thus, this study aimed to analyze the influence of environmental characteristics on the richness and occurrence of terrestrial mammals of medium and large size; as well as the spatio-temporal relationship between the top predator, mesopredator and preys, in the Atlantic foreste area continuos continuous with Serra do Mar State Park, with recent degradation history (Neblinas Park, Bertioga, State of São Paulo). Sample data was collected by camera trapping for 90 days in 2013 and 2014, 27 sampling points 1km distant from each other. The environmental characteristics were altitude, drainage density, average rainfall, average temperature, number of palm hearts (Euterpe edulis) and the presence of nature trails. Generalized Linear Models were used to analyze the environmental influences on the richness and occurrence of species (with more than 3 records per year). For the other analyses, species were grouped into predator, mesopredators, preys of large, medium and small size. The period and overlap activity of these groups were estimated by the Kernel density. Abundance was estimated for mesopredators and prey through N-mixture models. Single-season occupancy models were used to analyze the probability of occupancy and detection of top predators. A total of 18 terrestrial mammals of medium and large size were sampled, with nine of them being threatened with extinction: Cabassous unicinctus (naked-tailed armadillo), Cuniculus paca (paca), Leopardus guttulus (oncilla), Leopardus pardalis (ocelot), Leopardus wiedii (margay), Pecari tajacu (collared peccary), Puma concolor (cougar), Puma yagouaroundi (jaguarundi) and Tapirus terrestris (tapir). In the 2013, the species richness was positively influenced by the largest volume of precipitation and the species occurrence (C. unicinctus, Dasypus novemcinctus (tatu-galinha), P. concolor, Sylvilagus brasiliensis (tapiti) e T. terrestris) was interfered by the drainage density. In 2014, richness was not explained by any of the environmental characteristics mentioned and only four species have suffered influence of them. The top predator recorded was catemeral, the mesopredator and large prey were mainly nocturnal and prey of medium and small size were mainly daylight. Smaller prey had the highest total overlap with the predator (Δ1=0.72). The influence on the probability of occupancy of the area by the predator varied between the years: in 2013 it was the abundance of large and small preys, and in 2014, the influence was the abundance of medium preys. The detection was negatively influenced by the occasion only in 2014. Our findings showed the environmental characteristics that should be maintained in the area, such as water resources and abundance of prey, for conservation of Atlantic Forest and its fauna community.
25

Spatial Ecology of Coyotes and Cougars: Understanding the Influence of Multiple Prey on the Spatial Interactions of Two Predators

Mahoney, Peter J. 01 May 2017 (has links)
The extent to which predators regulate prey populations remains a subject of debate. Yet, when predator control is employed as a management strategy, it is often assumed that predators can and do regulate prey populations. From 2011 through 2015, I monitored the demography and space use of coyotes (Canis latrans) and cougars (Puma concolor) on Monroe Mountain in Fishlake National Forest, Utah as part of a larger collaboration investigating the impacts of coyote aerial control on mule deer (Odocoileus hemionus) neonate survival. My primary objective was to assess the impacts of anthropogenic regulation on the respective populations and identify any cascading effects relevant to mule deer management. To meet this objective, I established a monitoring program for both predators by deploying radio-telemetry collars (VHF and GPS) on each, documented predation events, established surveys for small mammals and lagomorphs to monitor primary prey populations during deer parturition (June – August), and collected data on the location and demographic composition of winter-removed coyotes. I analyzed these data primarily in a community-based, animal movement and resource selection framework permitting the integration of data from multiple sources. When evaluating coyote aerial removal as a management strategy, I identified a spatial dependency in the ability to match removals with indices of deer recruitment as Wildlife Services Operations personnel were primarily limited by terrain and tree cover. Thus, matching treatment with deer fawning was highly variable with only a small number of sites where removals were effective. In addition, I found that coyotes selected for sites with the highest densities of lagomorphs while avoiding areas with a high probability of encountering cougars. Coyotes did not select for mule deer fawning sites, although individual coyotes that occupied resource-poor home ranges were more likely to do so. Cougars strongly selected for mule deer high use areas throughout much of the year, only switching to elk (Cervus elaphus) during the cougar harvest season (i.e., winter). Data from cougar kill site investigations match the observed patterns in cougar space use. My results suggest that predator-prey processes are multi-dimensional and dynamic through time, which likely contribute to the lack of resolution regarding the efficacy of predator control and the regulatory potential of predators in general.
26

Cougar Predation Behavior in North-Central Utah

Mitchell, Dustin L. 01 May 2013 (has links)
Cougar (Puma concolor) predation has been identified as being one of several factors contributing to the decline of mule deer (Odocoileus hemionus) throughout the Western United States. In order to better understand how these elusive felines utilize their surroundings and prey, I examined and analyzed cougar predation behavior in North-Central Utah, using global positioning systems (GPS) data from 2002-2010. Twenty-three cougars were fitted with GPS collars and monitored for prey caching behavior. In total 775 potential cache sites were visited and 546 prey remains found. Mule deer comprised the majority of prey at cougar cache sites, but 11 other species were also found. Collectively, adult female mule deer were killed more than any other demographic class. Proportionally there was no difference in the sex or age class of deer killed by cougars in three different population segments, but seasonal differences were found in the number of kills made between cougar groups. Female cougars with kittens had a higher predation rate than males or solitary females, and seasonally more kills were made in the winter vs. summer. Cougars spent an average of 3.3 days on deer kills, and 6.2 days on elk kills. Habitat analyses suggested that cougars preferentially used Gambel oak (Quercus gambelii) over other land cover types when caching prey, as well as selected unburned over burned areas for caching and foraging on prey. These results suggest that cougars utilize dense stands of vegetation cover when stalking and concealing their prey. Wildlife managers may want to consider the use of prescribed burns in areas of high cougar predation on mule deer. This habitat manipulation tool could simultaneously help mule deer populations by reducing the percent of stalking cover afforded to cougars when attempting to kill prey, along with increasing nutrient levels of newly burned foliage and allow for an increased diversity in forb and shrub species available to mule deer.
27

Where Mountain Lions Traverse: Insights from Landscape Genetics in Southwestern United States and Northwestern Mexico

Naidu, Ashwin January 2015 (has links)
The projected growth in human population, rapid urbanization, and expansion of structures like highways and canals pose a major threat to the future survival of wildlife, particularly large terrestrial mammals. In many cases, wild animal populations have been restricted to fragmented habitat islands due to anthropogenic developments, endangering them to local extinction. Current and future wildlife conservation and management strategies are leading to the implementation of mitigation measures such as creation of wildlife habitat corridors. In this light, novel and interdisciplinary research methods such as approaches in the field of landscape genetics are proving to be increasingly useful and necessary for assessing the status of wildlife populations and furthering efficacy of conservation programs and management efforts. In this 5-year research study, I review literature in the field of landscape genetics, highlighting studies and their applications toward wildlife conservation over the past decade (2005-2014). I then use a landscape genetic approach to understand the potential impact of natural and human-made barriers in and around the northern Sonoran Desert on one of the widest-ranging mammals in the world, the mountain lion (Puma concolor). I employ recently developed genetic tools to assess the current population genetic status of mountain lions in this region and Geographic Information Systems (GIS) tools to relate observations to landscape features through interpretive maps. I further investigate the utility of GIS and expert-based models in connectivity conservation and suggest validating them with information on genetic relatedness and functional connectivity among mountain lions. Lastly, in many parts of this document, I emphasize the use of these methods and data sharing in conservation planning as well as wildlife management.
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Conserving cougars in a rural landscape: habitat requirements and local tolerance in west-central Alberta

Knopff, Aliah Adams Unknown Date
No description available.
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Seasonal Habitat Selection by Resident and Translocated Caribou in Relation to Cougar Predation Risk

Leech, Heather 17 April 2015 (has links)
Mountain caribou, an arboreal lichen-feeding ecotype of woodland caribou (Rangifer tarandus caribou), have been extirpated from much of their historic range. Mountain caribou are federally listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and red-listed by the BC government. Habitat loss and fragmentation of old growth forest is the ultimate cause for population declines. Yet, predation, linked to apparent competition, is the proximate cause for high rates of mortality. One of the most imperiled populations resides in the Purcell Mountains of BC, which was experimentally augmented in 2012 with 19 northern caribou from northern BC. The caribou-predator literature predominantly focuses on the relationship between caribou and wolves (Canis lupus) in northern caribou populations. However, cougars (Puma concolor) have been identified as a major predator of Purcells-South (PS) caribou, yet caribou-cougar interactions remain largely unstudied. I evaluated cougar predation risk in space and time on resident and translocated caribou in the Purcell Mountains. To do so, I determined biologically relevant seasons for resident, donor (i.e. not translocated) and translocated caribou, and cougars. I then used these seasons to investigate seasonal patterns of movement and habitat use between the three groups of caribou and cougars. Next I used resource selection functions (RSFs) to estimate habitat based seasonal variation in predation risk. I used these RSFs to compare the seasonal habitat selection and risk to cougar predation between resident and translocated caribou. Five resident caribou seasons and two cougar seasons were defined. Translocated caribou displayed inconsistent movement behavior with no clear seasonal pattern. Resident caribou remained at high elevations year-round and selected for low risk cougar habitat during the calving season at the home range scale and year-round at the landscape scale. Translocated caribou displayed risky behaviour throughout the study period by traveling to mid to low elevations and habitats selected by cougars. Translocated caribou displayed the same general pattern of elevational movement as their northern conspecifics, spending the majority of their time at lower elevations than resident caribou. Of the 19 translocated caribou, 17 (89%) died during the study, six of which were preyed upon by cougars, two by wolves, and the remainder due to accidents or unknown causes. In summary, translocated caribou did not adopt the predator avoidance or habitat selection strategies of resident caribou. I recommend that future efforts to augment small caribou populations use donor caribou experienced with similar predators and that possess comparable seasonal habitat use to the recipient population. However, because most suitable donor populations are declining, a soft-release of captive-reared mountain caribou might be the best option for mountain caribou recovery efforts. / Graduate / 0366 / 0329
30

Conserving cougars in a rural landscape: habitat requirements and local tolerance in west-central Alberta

Knopff, Aliah Adams 06 1900 (has links)
Maintaining large carnivores in human-dominated landscapes poses a significant conservation challenge. Extirpation is common because of habitat loss or direct persecution. I studied cougar habitat selection and human perception of cougars in west-central Alberta to better understand human-cougar coexistence. Cougars that were exposed to higher levels of development at the home-range scale exhibited less avoidance of anthropogenic features and altered habitat use temporally to accommodate variation in human activity, indicating behavioral resilience to development. Survey results showed that cougars were valued and tolerated by people, provided cougars did not occur near residences. Where human densities are increasing in moderately developed landscapes in west-central Alberta, therefore, human tolerance may currently be more important than habitat change for conserving cougar populations. Tolerance was negatively affected primarily by the risk (real and perceived) cougars pose to people, livestock, and game. Public education to counteract overestimation of risk may increase tolerance. / Ecology

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