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How competition dynamics drive access to shared scavenging opportunities amongst a group of mesocarnivores in the Rocky Mountains of AlbertaBell, Elicia 01 September 2021 (has links)
Mesocarnivores occupy critical functional roles in regulating ecosystems and maintaining biodiversity. In the Canadian Rocky Mountains, mustelid species depend heavily on carrion as an important dietary contribution, particularly in winter when resources are scarce. In diverse mesocarnivore communities such as this, sympatric species must balance energetic resource acquisitions through scavenging with avoidance of costly competition dynamics, in a manner that optimizes energetic gain through risk aversion. We examined the nature of spatial-temporal interactions between wolverine (Gulo gulo), American marten (Martes Americana), and short-tailed weasel (Mustela erminea) in the Willmore Wilderness Park in western Alberta. Data were collected from camera traps (n = 59) baited with a simulated scavenging opportunity during winter months between 2006 to 2008. The spatial-temporal dimensions of intraguild competition were evaluated using a multi-model approach. Zero-inflated negative binomial (ZINB) or zero-inflated Poisson (ZIP) regression models were used to identify the competitive and environmental factors that affected (1) species presence/absence and (2) how intensely a species would spatiotemporally optimize a carrion site. A time-to-event analysis was used to quantify the directionality of fine-scale (hourly) reactionary behavioural responses of species to potential sources of competition. An extension of this group of models, the Cox proportional hazard (CPH) model was used to further reveal the relative influence of external environmental variables (i.e. diel period, landcover, and snow depth) on temporal spacing. Pairing CPH and ZINB/ZIP models enables us to recognize the relative contribution of fine-scale spatial and temporal behavioural responses to competitors in shaping coexistence strategies.
Our results suggest that facultative scavengers adopt different coexistence mechanisms based on the interspecific competitor and environmental conditions they encounter at carrion sites. We found that carrion use was impacted for all species by competition and snow depth. Marten scavenging behaviours were additionally impacted by habitat character. We also found evidence of fine-scale temporal attraction between marten and wolverine, thought to indicate a shared net-energetic gain at scavenging sites. Our results suggest that mesocarnivore scavengers are likely to adopt spatiotemporal mechanisms to facilitate carrion resource partitioning and adapt to conditions specific to carcass placement in a spatially complex environment. Given their vital ecological roles, it is important that we recognize the ability of individual mustelid species to exploit scavenging opportunities and identify the external factors that influence coexistence. Understanding the factors that drive access to these ephemeral resources will provide valuable information for anticipating impacts of climate change on facultative scavengers in the boreal forests of western Canada. / Graduate / 2022-08-23
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RECOVERY OF THE EASTERN WOODRAT IN SOUTHERN ILLINOIS: DISTRIBUTION, DEMOGRAPHICS, AND NONINVASIVE MONITORINGGooley, Aaron Clinton 01 May 2019 (has links)
Woodrats (Neotoma spp.) are imperiled in the north-central and north eastern United States. In Illinois, eastern woodrats (N. floridana) experienced range reductions and population bottlenecks over the past century. Hypothesized reasons for the decline of many woodrat populations that inhabit rock outcrops in the eastern United States include parasitism by raccoon roundworms (Baylisascaris procyonis), hard mast shortages, owl predation, and reductions in crevice availability for nest construction. During 2004-2005, the isolated remnant populations along the Mississippi bluffs in southwestern Illinois were genetically augmented with 47 eastern woodrats from Arkansas and Missouri resulting in 40% admixture within the largest population. In 2009, a strong windstorm created canopy gaps and woody debris throughout this area, potentially improving habitat for eastern woodrats. During 2003–2009, 422 eastern woodrats were reintroduced to 5 sites in the southeastern Illinois, and 172 eastern woodrats to 2 southern Illinois state parks during 2013–2014. These reintroductions are the only woodrat reintroductions to date with >50 individuals released per site. Most previous woodrat reintroduction attempts have released small numbers of individuals (10–15 per site and 10–54 total) and either failed to establish populations or required frequent management for populations to persist. My objectives were to (1) investigate the status of augmented eastern woodrat populations in southwestern Illinois, (2) evaluate the success of the southern Illinois reintroductions, (3) investigate whether eastern woodrats demographics within a reintroduced metapopulation could be predicted by factors underlying hypothesized reasons for woodrat declines, and (4) develop and evaluate noninvasive alternatives to live-trapping and sign surveys for monitoring woodrat populations.
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Relationships Among Invasive Coqui Frogs, the Small Indian Mongoose and Rat Species in HawaiiHill, Shane A. 01 August 2018 (has links)
Non-native species are increasing globally, and with this increase, it is likely that there will be new, unique relationships found among non-natives as well as additional impacts on native species. Rats and mongooses have been introduced to islands throughout the world where they impact native species, including birds, reptiles, and amphibians. The coqui frog was introduced to Hawaii in the 1980’s, where there were already abundant rat and mongoose populations. Previous research suggests that the high densities of coqui frogs may provide enough of a new food source for mongooses and rats that their populations would grow larger than they would without coqui frogs, and that this would exacerbate the negative effects that these predators have on native birds.
We investigated whether there are relationships between coqui presence, and the local abundance of introduced rats and mongoose on the island of Hawaii. We also investigated at these 12 sites whether there were indirect effects of coquis on bird nest predation rates using camera traps on artificial nests. Finally, we interpret our results in light of an analysis of the stomach contents of mongooses and rats, and data collected from remote cameras monitoring scavengers of dead coqui frogs.
We compared abundances of mammals in coqui invaded plots and uninvaded plots. In areas where coquis were present, we found a greater number of mongooses, and less Pacific rats. Both predators consume coquis, but mongooses were more important consumers of live and dead coquis. Shifts in mongoose and rat diets were observed in coqui invaded and uninvaded plots. It may be that coqui frogs are competing with rats because we found more fruit in rat stomachs collected in coqui invaded compared to uninvaded plots. We did not observe any difference in nest predation rates with and without coquis. Our results show that the coqui may serve as novel prey and/or competitors to non-native mammals.
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The ecology of the lowland tapir in Madre de Dios, Peru: Using new technologies to study large rainforest mammalsTobler, Mathias Werner 15 May 2009 (has links)
The objectives of my research were twofold: 1) to evaluate new technologies (camera
traps and a new type of GPS collar) for studying large mammals in tropical forests, and
2) to study the ecology of the lowland tapir (Tapirus terrestris) in the Peruvian Amazon.
Camera traps proved to be an efficient tool for mammal inventories in tropical forests.
They recorded 24 out of 28 terrestrial medium and large sized mammal species with a
survey effort of 2340 camera days. Camera traps were also able to reveal important
information on habitat use, activity patterns and the use of mineral licks for five
Amazonian ungulate species. There was a high spatial overlap between all the species
with the grey brocket deer being the only species that was restricted to terra firme forest.
White-lipped peccaries, tapirs and red brocket deer frequently used mineral licks,
whereas collared peccaries and grey brocket deer were hardly ever observed at licks.
A new type of GPS collar (TrackTag) tested in this study performed well under the
dense canopy of a tropical forest. Position success rates of 87% for stationary collars and
48% for collars placed on tapirs were comparable to data obtained with GPS collars in
temperate forests. The mean location error for stationary collars inside the forest was
28.9 m and the 95% error was 76.8 m.
GPS collars placed on six tapirs for seven to 182 days showed home range sizes of 102
to 386 hectares. Tapirs were mainly nocturnal and areas used for foraging during the
night differed from resting sites used during the day. Tapirs could walk up to 10 km to
visit a mineral lick. Visits were irregular at intervals of a few days up to 36 days. The analysis of 135 tapir dung samples showed that tapirs ingest seeds of over 120 plant
species. Seeds were found throughout the year but monthly species diversity was related
to fruit availability. The size distribution of ingested seeds was related to availability.
Most seeds were less then 10 mm wide, but seeds up to 25 mm were found.
Both camera traps and TrackTag GPS collars greatly increased the possibilities for
studying large rainforest mammals. The two technologies collect complementary
information and each one is suited for a different set of questions.
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The Impact of Human Presence on Terrestrial Mammals in Secondary Regenerating Forest of the Peruvian AmazonPandya, Duncan January 2023 (has links)
Human disturbance is becoming an ever-bigger threat to biodiversity across the globe and should continue to be a field of conservation priority. Urbanisation, research and tourism put unavoidable pressure on the surrounding flora and fauna, therefore we need to gain knowledge on how to reduce future harm. Here we investigated the effects of human presence on medium-large terrestrial mammals in the south-eastern Peruvian Amazon, using camera traps to measure the number of human and mammal observations at varying distances from our research centre and the hiking trails. Species richness and the Shannon and Inverse Simpson diversity indices were also calculated during the four-month study period. Nineteen species were detected across fourteen camera sites. Distance from camp was positively correlated with species richness and the diversity indices, but showed no correlation with total mammal observations. Distance from nearest trail was negatively correlated with species richness, total mammal observations and the diversity indices. Total human observations was negatively correlated with species richness and the diversity indices, but had no impact on total mammal observations. Nevertheless, these results often had high p-values and low sample size and therefore should be interpreted with caution. Omnivores were the most sensitive trophic guild, showing a statistically significant negative correlation with total human observations, and a statistically significant positive correlation with distance from nearest trail. It is important then to assess these responses to human disturbance at the community and species level, as to truly understand the impact we are having.
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Anthropogenic effects on site use and temporal patterns of terrestrial mammals in Harenna Forest, EthiopiaGichuru, Phillys Njambi 22 March 2022 (has links)
There has been little research comprehensively documenting wildlife species in Harenna Forest within the Bale Mountains National Park of Ethiopia. This area is one of the few remaining afro-alpine biodiversity hotspots and is home to numerous endemic plants and animals and offers socio-economic benefits to the neighboring communities. Human population pressure, weak land protection policies, and uncertain land tenure rights have led to increases in farmland for subsistence and coffee farming, livestock grazing, and reduction of afro-alpine, shrubland and grassland habitats. Given these challenges, I used 48 camera trap stations to produce an inventory of wildlife species and to determine factors influencing occupancy (i.e., habitat use), detection, and temporal activity and overlap. I recorded 26 terrestrial and arboreal mammalian species and I had sufficient data to model occupancy for 13 species and temporal activity for 14 species. Occupancy and detection were generally higher for herbivores and omnivores (occupancy: 0.28-0.97; detection: 0.1-0.54) than carnivores (occupancy: 0.31-0.80; detection: 0.04-0.18). I found more evidence of positive anthropogenic impacts on herbivore and omnivore occupancy than negative, while detection was influenced by habitat or landscape features, rather than by humans. Carnivore occupancy was largely unaffected by anthropogenic or habitat variables, but detection was strongly, and mostly positively, influenced by anthropogenic impacts.
Temporal activity analyses revealed that, for herbivores and omnivores, only tree hyraxes (Dendrohyrax arboreus) and crested porcupines (Hystrix cristata) were nocturnal, Menelik bushbucks (Tragelaphus scriptus meneliki) were crepuscular, and the remaining species ranged from diurnal to cathemeral. Neither similar body size nor similar diet affected overlap between species pairs. However, overlap with human temporal activity was low for Menelik bushbucks (Δ=0.45) and common duikers (Sylvicapra grimmia) appeared to become less active at stations with high human use. For carnivores, leopards (Panthera pardus) and honey badgers (Mellivora capensis) were crepuscular, and the remaining species were nocturnal. I found evidence that carnivores overlapped less when they were more similar in body size to other carnivores (average Δ=0.67-0.71) compared to species more dissimilar in body size (average Δ=0.75), although there was variation across species. In general, carnivores overlapped much less with humans (average Δ=0.20) than did herbivores (average Δ=0.52) and omnivores (average Δ=0.43). Spotted hyenas (Crocuta crocuta), in particular, appeared to alter activity to reduce overlap with humans.
This study provides baseline information on presence, distribution, and activity of large- and medium-sized terrestrial and arboreal mammals in an understudied biodiversity hotspot. My findings are concerning for biodiversity conservation as rare and endangered species (e.g., mountain nyalas (Tragelaphus buxtoni), Ethiopian wolves (Canis simensis)) were rarely or never photographed, and larger carnivores (e.g., lions (Panthera leo), leopards, jackals), generally had low capture rates. The species with higher capture rates, occupancy, and activity tended to be those that can tolerate or take advantage of human activity and disturbance. Species sensitive to human disturbance eventually may be lost unless measures can be put in place to reduce human impacts. This baseline knowledge is important for future studies examining trends in mammalian wildlife populations, such as site extinction and colonization, or changes in overlap with humans, in a landscape that is continuing to experience human-caused, landscape change. / Master of Science / Harenna forest, which is located in Bale Mountains National Park, Ethiopia is an important habitat to both wildlife and people. However, it faces a number of challenges as a result of population growth leading to increased coffee farming and livestock grazing resulting in reduced habitat for wildlife species. I used 48 cameras located across the forest to record presence of terrestrial mammals and document their distribution and daily activity across the landscape. I also used data such as vegetation indices, elevation, and distances to human-disturbed areas to determine what influenced wildlife species. Cameras recorded 26 species of mammals. I had enough data to determine distribution for 13 species and daily activity for 14 species. I found that presence across the landscape and activity of herbivores and omnivores was generally higher than that of carnivores. Additionally, I found that human activity or disturbance often had a positive influence on herbivore and omnivore distribution, but my ability to detect species in camera traps was primarily influenced by habitat or landscape features. Carnivore distribution on the landscape was not influenced much by humans or habitat, but their detectability was often positively influenced by presence of humans.
In addition to daily activity, I also analyzed overlap in activity between species pairs and between species and humans, to determine whether wildlife changed their temporal activity to overlap less with similar sized competitors or in response to high human use. For herbivores and omnivores, I found that tree hyraxes and crested porcupines were active at night, Menelik's bushbucks were active at sunrise and sunset, and cape bushbucks, common duiker, olive baboon, bushpig, and giant forest hogs were active either during the day or throughout the day and night. I found little evidence that the herbivores or omnivores avoided each other temporally and only the Menelik bushbuck and duiker appeared to avoid humans. For carnivores, I found that leopards and honey badgers were active early morning and evening, and the common genet, African civet, white-tailed mongoose, and spotted hyenas were all active at night only. Carnivores generally overlapped less with humans than herbivores and omnivores. I found some evidence that carnivores more similar in body size had lower temporal overlap with each other and that spotted hyaenas appeared to avoid activity during times of day when humans were active.
My study not only provides baseline information on terrestrial and arboreal mammals present in Harenna forest, Ethiopia, but is also necessary for understanding how wildlife species use the landscape and particularly how presence of humans influences wild animal behavior. My findings are concerning for biodiversity conservation because I had few to no photographs, respectively, of the endangered mountain nyala and Ethiopian wolf. In fact, most of the species with a wide distribution on the landscape, or with high activity, were common or smaller species that are tolerant of, or could take advantage of, human disturbance. Without concerted effort to curtail the current landscape change caused by humans, the area is likely to lose species less tolerant of humans, and biodiversity will ultimately decline.
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Ocupação de paisagens dentro e fora de unidades de conservação pelo veado-catingueiro (Mazama gouazoubira Fischer, 1814) no nordeste paulista / Estimating occupancy of protected areas and buffer zones by brown brocket deer (Mazama gouazoubira Fischer, 1814) in the northeast of Sao Paulo StateRodrigues, Thiago Ferreira 08 June 2015 (has links)
O nordeste paulista é composto por um mosaico de ambientes fortemente antropizado, com predominância de plantios de cana-de-açúcar, além de florestas plantadas de eucalipto e fragmentos de Cerrado. Embora o veado-catingueiro (Mazama gouazoubira) seja uma espécie amplamente distribuída em diferentes biomas do Brasil, pouco é conhecido sobre a sua capacidade de adaptação em paisagens alteradas. Neste contexto, modelos de ocupação da paisagem e dados de armadilhas fotográficas foram utilizados para verificar quais fatores ambientais são importantes na escolha do uso e seleção de hábitat pelo veado-catingueiro. Foram amostradas quatro áreas em três cenas de paisagens, entre os meses de Abril e Setembro de 2013 e 2014, totalizando um esforço amostral de 6240 armadilhas/dia. Os resultados apontam que o veado-catingueiro está amplamente distribuído nos remanescentes de Cerrado do nordeste do estado de São Paulo, além de ocupar com a mesma intensidade tanto o interior como o entorno de unidades de conservação. Foi observado um efeito positivo dos plantios de silvicultura na ocupação da paisagem pela espécie. A distribuição temporal dos registros ao longo do ciclo de 24 horas também foi semelhante dentro e fora de unidades de conservação. Estes resultados sugerem que o veado-catingueiro é uma espécie ecologicamente plástica e que está se beneficiando da heterogeneidade ambiental presente no nordeste paulista. Estes hábitos generalistas lhe atribuem vantagens em comparação a outras espécies mais especialistas nesse cenário. / The northeast of São Paulo state is a region where Cerrado remants are immersed in a landscape with high human influence mediated by vast sugarcane and Eucalyptus plantations. Mammals survival in this landscape has been little explored. Brown brocket deer (Mazama gouazoubira, Fischer 1814) is a species with widespread distribution in different biomes of Brazil, however little is known about its capacity of adaptation in landscapes with intensive agriculture. We conducted a study based on occupancy modelling from camera trapping data in order to evaluate which environmental factors are important to habitat selection by brown brocket deer. The study was carried out in three agricultural landscapes at four study areas between April and September (2013 and 2014) with a total effort of 6240 traps-day. Our results show that brown brocket deer are well adapted to Cerrado/agricultural matrix in the state of Sao Paulo, showing high ecological flexibility. This deer used non-protected areas as much as protected areas. Silviculture represented the only landscape covariate with high relative importance for brown brocket deer. Also, brown brocket deer shows rhythm of activity similar in and out protected areas. Our results suggest that brown brocket deer is extremely plastic species that is benefiting from environmental heterogeneity present in São Paulo\'s northeast. The generalist habit of this deer gives it advantage when compared to other more specialist species in this scenario.
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AVALIAÇÃO DA RIQUEZA E ABUNDÂNCIA DE ESPÉCIES DE MAMÍFEROS DE MÉDIO E GRANDE PORTE EM FRAGMENTOS FLORESTAIS NO MUNICÍPIO DE GOIÂNIA, GOIÁS, BRASIL. / Evaluation of richness and abundance of medium and large size mammals species in forest fragments in Goiania, Goias, Brazil.Neves, Kelle Cristina 15 August 2012 (has links)
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Previous issue date: 2012-08-15 / The landscape constantly changed, caused mainly by human activities, have
affected the size, shape and frequency of the landscape elements, and these
fragmentation effects have been some of the major threats to biodiversity and
changes in species behavior. This study was made in urban forest fragments in the
city of Goiania, Goias with the intention of evaluating the richness, the abundance of
the medium and large size mammals relating with the area size and the environment
heterogeneity of the fragments. We only used the method of camera trapping
(camera trap) to raise the wealth and abundance and we collected points of the
vegetation structure along 11 forest fragments in areas between 9,76 and 126,95ha,
testing such hypotheses: (1) the larger the forest fragment the larger the record of
richness of the species, (2) the larger the forest fragment the larger the species
abundance and (3) fragments found in abundance is explained by environmental
variables fragments. We obtained 180 records of medium and large size mammals in
a total of 20 species, 8 orders and 13 families. The species of greatest occurrence
and registration was the coati (Nasua nasua). We recorded a specie classified as
vulnerable according to IUCN and MMA, which is the Giant anteater (Myrmecophaga
tridactyla) and White-lipped Peccary (Tayassu pecari) appears in the list of IUCN as
near threatened. Medium and large size species when it comes to richnes and
abundance did not obbey an area, they were found in the smaller area as much as in
the larger area. The environmental heterogenety in the fragments also did not explain
the abundance found in the areas, reforcing the need and how important is the
maintenance and conservation of the Cerrado and of all of the areas sizes, which can
serve as the only and temporary source (increasing the connectivity between
species). / A paisagem constantemente alterada causada principalmente pelas
atividades humanas tem afetado o tamanho, a forma e a frequência dos elementos
da paisagem, e esses efeitos da fragmentação tem sido algumas das principais
ameaças à biodiversidade e mudanças no comportamento das espécies. Este
estudo foi realizado em fragmentos florestais urbanos no município de Goiânia,
Goiás com o intuito de avaliar a riqueza, a abundância dos mamíferos de médio e
grande porte relacionando com o tamanho da área e a heterogeneidade ambiental
dos fragmentos. Utilizamos exclusivamente o método de armadilhas fotográficas
(câmera trap) para levantar a riqueza e a abundância e coletamos pontos da
estrutura da vegetação ao longo de 11 fragmentos florestais com áreas que variaram
de 9,76 a 126,95 ha, testando as seguintes hipóteses (1) quanto maior o fragmento
florestal maior a riqueza das espécies, (2) quanto maior o fragmento florestal maior a
abundância das espécies e (3) abundância encontrada nos fragmentos é explicada
pelas variáveis ambientais dos fragmentos. Foram obtidos 180 registros de
mamíferos de médio e grande porte em um total de 20 espécies, 8 ordens e 13
famílias. A espécie de maior ocorrência e registro foi o quati (Nasua nasua).
Registramos uma espécie classificada como vulnerável de acordo com a IUCN e
MMA que foi o tamanduá-bandeira (Myrmecophaga tridactyla) e queixada (Tayassu
pecari) que consta na lista da IUCN como quase ameaçada. As espécies de médio e
grande porte quanto a riqueza e a abundância não necessariamente obedeceu a um
crescimento com o aumento da área, elas foram encontradas tanto em fragmentos
de menor área quanto de maior área. A heterogeneidade ambiental nos fragmentos
também não explicou a abundância encontrada nas áreas reforçando a necessidade
e a importância da manutenção e conservação do Cerrado e de todos os tamanhos
de áreas, que podem servir como fonte única e/ou como temporária (aumentando a
conectividade entre espécies).
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Ocupação de paisagens dentro e fora de unidades de conservação pelo veado-catingueiro (Mazama gouazoubira Fischer, 1814) no nordeste paulista / Estimating occupancy of protected areas and buffer zones by brown brocket deer (Mazama gouazoubira Fischer, 1814) in the northeast of Sao Paulo StateThiago Ferreira Rodrigues 08 June 2015 (has links)
O nordeste paulista é composto por um mosaico de ambientes fortemente antropizado, com predominância de plantios de cana-de-açúcar, além de florestas plantadas de eucalipto e fragmentos de Cerrado. Embora o veado-catingueiro (Mazama gouazoubira) seja uma espécie amplamente distribuída em diferentes biomas do Brasil, pouco é conhecido sobre a sua capacidade de adaptação em paisagens alteradas. Neste contexto, modelos de ocupação da paisagem e dados de armadilhas fotográficas foram utilizados para verificar quais fatores ambientais são importantes na escolha do uso e seleção de hábitat pelo veado-catingueiro. Foram amostradas quatro áreas em três cenas de paisagens, entre os meses de Abril e Setembro de 2013 e 2014, totalizando um esforço amostral de 6240 armadilhas/dia. Os resultados apontam que o veado-catingueiro está amplamente distribuído nos remanescentes de Cerrado do nordeste do estado de São Paulo, além de ocupar com a mesma intensidade tanto o interior como o entorno de unidades de conservação. Foi observado um efeito positivo dos plantios de silvicultura na ocupação da paisagem pela espécie. A distribuição temporal dos registros ao longo do ciclo de 24 horas também foi semelhante dentro e fora de unidades de conservação. Estes resultados sugerem que o veado-catingueiro é uma espécie ecologicamente plástica e que está se beneficiando da heterogeneidade ambiental presente no nordeste paulista. Estes hábitos generalistas lhe atribuem vantagens em comparação a outras espécies mais especialistas nesse cenário. / The northeast of São Paulo state is a region where Cerrado remants are immersed in a landscape with high human influence mediated by vast sugarcane and Eucalyptus plantations. Mammals survival in this landscape has been little explored. Brown brocket deer (Mazama gouazoubira, Fischer 1814) is a species with widespread distribution in different biomes of Brazil, however little is known about its capacity of adaptation in landscapes with intensive agriculture. We conducted a study based on occupancy modelling from camera trapping data in order to evaluate which environmental factors are important to habitat selection by brown brocket deer. The study was carried out in three agricultural landscapes at four study areas between April and September (2013 and 2014) with a total effort of 6240 traps-day. Our results show that brown brocket deer are well adapted to Cerrado/agricultural matrix in the state of Sao Paulo, showing high ecological flexibility. This deer used non-protected areas as much as protected areas. Silviculture represented the only landscape covariate with high relative importance for brown brocket deer. Also, brown brocket deer shows rhythm of activity similar in and out protected areas. Our results suggest that brown brocket deer is extremely plastic species that is benefiting from environmental heterogeneity present in São Paulo\'s northeast. The generalist habit of this deer gives it advantage when compared to other more specialist species in this scenario.
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APPLICATION OF ADVANCED DIGITAL TECHNOLOGY FOR WILDLIFE HABITAT MODELINGJessica Marie Elliott (12470109) 28 April 2022 (has links)
<p> </p>
<p>In recent decades, wildlife studies have begun to incorporate more structural characteristics into studies of habitat. However, most still collect habitat data primarily from field measurements, which are limited in spatial extent and force researchers to extrapolate from small-scale, ground-based measures. LiDAR offers the opportunity to objectively measure habitat features across landscape-level extents. I mapped and measured forest canopy structural diversity at 181 plots across Indiana at a series of three (25-m, 50-m, and 100-m) radii to quantify landscape heterogeneity across space, utilizing new 2016–2020 aerial LiDAR in tandem with high-resolution camera traps. I aimed to quantify the relationship between use of forest sites by seven wildlife species and habitat structural characteristics, specifically predicting species occupancy as a function of LiDAR-derived metrics. I predicted that habitat generalists like raccoons (<em>Procyon lotor</em>) and Virginia opossum (<em>Didelphis virginiana</em>) would be best predicted by the null hypothesis and that measures of gap fraction would best predict edge species such as coyote (<em>Canis latrans</em>), white-tailed deer (<em>Odocoileus virginianus</em>), and wild turkey (<em>Meleagris gallopavo</em>). Additionally, I predicted a positive relationship between vegetation area and both eastern cottontail rabbit (<em>Sylvilagus floridanus</em>) and tree squirrels (Sciuridae spp.). I expected that measures of habitat heterogeneity would be included in best models for tree squirrels and white-tailed deer, and that models for squirrels would have lower root mean square error (RMSE) values. Ultimately, structural metrics varied across radii, and best models depended on plot radius size. Measures of vertical heterogeneity were the best predictors for species like raccoon, wild turkey, and coyote, with a higher probability of occupancy for all three with increased heterogeneity. Additionally, models for eastern cottontail rabbit incorporating vegetation area indices, Gini diversity, and gap fraction demonstrated significance and low predictive error. Habitat generalists, such as white-tailed deer and Virginia opossum did not select for specific structural metrics and were best predicted by the null model. Ultimately, these results indicated that LiDAR is a promising potential tool for measuring ecologically meaningful variables at scales large enough to properly represent home range and resource use at the home-range level, filling an important gap in our understanding. </p>
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