The Experts below are selected from a list of 1995 Experts worldwide ranked by ideXlab platform
Ivan Castro-arellano - One of the best experts on this subject based on the ideXlab platform.
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Temporal coexistence in a carnivore assemblage from central Mexico: temporal-domain dependence
Mammal Research, 2019Co-Authors: Yuriana Gómez-ortiz, Octavio Monroy-vilchis, Ivan Castro-arellanoAbstract:Species coexistence at a given locality generally implies segregation along one of the three resource dimensions of the ecological niche: spatial, trophic or temporal. Temporal activity patterns of species are ecologically important as they expose how species exploit their environments. Using camera traps, we evaluated the temporal activity patterns and temporal overlap for a mammalian carnivore assemblage from Sierra Nanchititla Natural Park, central Mexico. We characterized and compared temporal activity patterns and temporal overlap between species pairs using circular statistics. Temporal overlap was analyzed using three temporal domains (full diel, diurnal, and nocturnal), and null models were used to contrast the empirical assemblage-wide temporal overlap in relation to randomly generated distributions. We found that pair-wise temporal overlap comparisons among species were quite heterogeneous and dependent on the temporal domain used for the analyses. Two major inferences can be derived from pair-wise analyses and the null model: (a) most of the carnivore assemblage show a nocturnal activity pattern in common and (b) most of the pair-wise comparisons indicate temporal segregation among species. The highest temporal overlap at the assemblage-wide level was found when only the nocturnal domain was evaluated and we found coincident temporal activities at the full domain level, independent of the temporal resolution used. Overall, our results suggest that carnivores with distinct trophic and habitat use like the margay ( Leopardus wiedii ) and Gray Fox ( Urocyon cinereoargenteus ) had temporal overlapping activity patterns to full diel and nocturnal domains, and species with similar trophic and habitat use always presented temporal segregation (Gray Fox and white-nosed coati, Nasua narica ). Finally, species with predator-prey relationships (white-nosed coati and cougar, Puma concolor ) showed segregation during the day but overlap at night. Our results indicate that species temporal activity patterns likely change in relation to different interspecific interactions such as predation and competition to allow species coexistence within this carnivore assemblage.
Jesús E. Maldonado - One of the best experts on this subject based on the ideXlab platform.
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Phylogeography of the Gray Fox (Urocyon cinereoargenteus) in the eastern United States
Journal of Mammalogy, 2011Co-Authors: Christine A. Bozarth, Stacey L. Lance, David J. Civitello, Julie L. Weston Glenn, Jesús E. MaldonadoAbstract:Molecular data have been used to show northward post-Pleistocene range expansions from a refugium in the southeastern United States for several mammal species. Fossil and historical records indicate that Gray Foxes (Urocyon cinereoargenteus) were not present in the northeastern United States until well after the Pleistocene (ca. 900). To test the hypothesis that Gray Foxes experienced a post-Pleistocene range expansion we conducted a phylogeographic analysis of Gray Foxes from across the eastern United States. We sequenced a variable portion of the mitochondrial control region (411 base pairs) from 229 Gray Fox tissue samples from 15 states, representing the range of all 3 East Coast subspecies. Phylogeographic analyses indicated no clear pattern of genetic structuring of Gray Fox haplotypes across most of the eastern United States. However, when haplotype frequencies were subdivided into a northeastern and a southern region, we detected a strong signal of differentiation between the Northeast and the rest of the eastern United States. Indicators of molecular diversity and tests for demographic expansion confirmed this division and suggested a very recent expansion of Gray Foxes into the northeastern states. Our results support the hypothesis that Gray Foxes 1st colonized the Northeast during a historical period of hemisphere-wide warming, which coincided with the range expansion of deciduous forest. We present the 1st study that analyzes the phylogeographic patterns of the Gray Fox in the eastern United States.
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relative abundance of endangered san joaquin kit Foxes vulpes macrotis mutica based on scat detection dog surveys
Southwestern Naturalist, 2006Co-Authors: Deborah A. Smith, Katherine Ralls, Brian L. Cypher, Howard O. Clark, Patrick A. Kelly, Daniel F. Williams, Jesús E. MaldonadoAbstract:Abstract Although the San Joaquin kit Fox (Vulpes macrotis mutica) has been a federally protected subspecies since 1967, current information on its status throughout much of its historical range is lacking. Since 1983, only 5 surveys have been conducted, and a recent recovery plan emphasized the need for better information on the status of this subspecies. Between 2001 and 2003, we attempted to obtain new information on this kit Fox on specific public and private properties in 8 counties in the San Joaquin Valley, California, where knowledge of its current status was limited or poorly understood. We used a trained detection-dog to survey for kit Fox, red Fox (V. vulpes), and Gray Fox (Urocyon cinereoargenteus) scats on selected properties, followed by species identification based on genetic analysis of DNA extracted from all scats collected. Despite extensive survey efforts (539 km), kit Fox was only detected in Merced County, in the area of Santa Nella, where a small kit Fox population was previously doc...
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RELATIVE ABUNDANCE OF ENDANGERED SAN JOAQUIN KIT FoxES (VULPES MACROTIS MUTICA) BASED ON SCAT–DETECTION DOG SURVEYS
The Southwestern Naturalist, 2006Co-Authors: Deborah A. Smith, Katherine Ralls, Brian L. Cypher, Howard O. Clark, Patrick A. Kelly, Daniel F. Williams, Jesús E. MaldonadoAbstract:Abstract Although the San Joaquin kit Fox (Vulpes macrotis mutica) has been a federally protected subspecies since 1967, current information on its status throughout much of its historical range is lacking. Since 1983, only 5 surveys have been conducted, and a recent recovery plan emphasized the need for better information on the status of this subspecies. Between 2001 and 2003, we attempted to obtain new information on this kit Fox on specific public and private properties in 8 counties in the San Joaquin Valley, California, where knowledge of its current status was limited or poorly understood. We used a trained detection-dog to survey for kit Fox, red Fox (V. vulpes), and Gray Fox (Urocyon cinereoargenteus) scats on selected properties, followed by species identification based on genetic analysis of DNA extracted from all scats collected. Despite extensive survey efforts (539 km), kit Fox was only detected in Merced County, in the area of Santa Nella, where a small kit Fox population was previously doc...
Michael J. Chamberlain - One of the best experts on this subject based on the ideXlab platform.
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Gray Fox home range, spatial overlap, mated pair interactions and extra-territorial forays in southwestern Georgia, USA
Wildlife Biology, 2017Co-Authors: Nicholas R. Deuel, Michael J. Chamberlain, L. Mike Conner, Karl V. Miller, Michael J. Cherry, Lawrence V. TannenbaumAbstract:Despite numerous studies estimating Gray Fox Urocyon cinereoargenteus home range sizes, there have been few studies to evaluate more nuanced space use patterns; thus little is known about Gray Fox spatial ecology beyond estimates of home range size. We used GPS-technology to track 34 Gray Foxes (20 males and 14 females) from February 2014 until December 2015 in southwestern Georgia, USA. Home range sizes were similar among seasons (p > 0.05), but core area sizes were smaller during spring than during winter and summer (p < 0.05). As would be expected, home range overlap was much greater between mated pairs than among neighboring animals and core area overlap among neighbors did not occur. Members of a mated pair apparently interacted frequently, with 29.4% of all simultaneous locations occurring within 40 m of each other. Members of mated pairs interacted more diurnally during spring (49.9%) which is concurrent with denning, than during summer (31.5%), while nocturnal interactions were similar during spring (18.0%) and summer (19.3%). We recorded 25 extra-territorial forays from 10 of 26 Gray Foxes. Three male Foxes were responsible for nearly half (12) of these forays. Because these forays took place during the breeding season, we suggest males may have been seeking extra-pair copulations.
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Location, spatial arrangement, and percentage of vegetation types in Southwestern Georgia, USA at a site used to study Gray Fox habitat selection from February 2014 to December 2015.
2017Co-Authors: Nicholas R. Deuel, Michael J. Chamberlain, Karl V. Miller, Michael J. Cherry, Mike L. Conner, Larry V. TannenbaumAbstract:Location, spatial arrangement, and percentage of vegetation types in Southwestern Georgia, USA at a site used to study Gray Fox habitat selection from February 2014 to December 2015.
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Spatial Ecology, Survival and Cause-Specific Mortality of Gray Foxes (Urocyon cinereoargenteus) in a Longleaf Pine Ecosystem
The American Midland Naturalist, 2010Co-Authors: Danielle L. Temple, Michael J. Chamberlain, L. Mike ConnerAbstract:Abstract Gray Fox ecology is poorly understood within the longleaf pine ecosystem, despite the importance of these landscapes to conservation and biological diversity. During 2002–2006, we radio-monitored 42 Gray Foxes and estimated space use, habitat selection and survival within a managed longleaf pine forest. Sizes of home ranges and core areas were greater in winter than during other seasons, but were similar between males and females. Industrial agriculture field and residential areas were important to Foxes when selecting home ranges, but hardwood forest stands were selected when establishing core areas and were consistently used more than other habitats. Despite being captured within the longleaf pine community, most Foxes either consistently were found outside of this system in other habitats, or used habitats along the periphery of the longleaf pine system. Mean annual survival was 0.61, and human-induced factors (vehicle collisions and trapping) accounted for most (63%) Fox mortalities. Longleaf...
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Infectious Canine Hepatitis in a Gray Fox (Urocyon cinereoargenteus)
Journal of Wildlife Diseases, 2007Co-Authors: Richard W. Gerhold, Andrew B. Allison, Danielle L. Temple, Michael J. Chamberlain, Karen Strait, Michael K KeelAbstract:A free-ranging adult male Gray Fox (Urocyon cinereoargenteus) with moderate diarrhea and thick ocular mucus discharge was examined postmortem. Microscopically, the Fox had intranuclear inclusion bodies within hepatocytes. Canine adenovirus-1 was identified by polymerase chain reaction (PCR) and nucleotide sequencing. To our knowledge, this is the first report of clinical infectious canine hepatitis in a Gray Fox.
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Movements and space use of Gray Foxes (Urocyon cinereoargenteus) following mate loss
The American Midland Naturalist, 2002Co-Authors: Michael J. Chamberlain, Bruce D. LeopoldAbstract:Abstract Effects of mate loss on Gray Fox behavior are poorly understood. We examined space use and gross movements of mated Gray Foxes following loss of their respective mates in central Mississippi during 1994–1997. We monitored 9 mated pairs of Gray Foxes and documented 4 instances of mate loss. Of 2 instances where the remaining pair member was a male, 1 male substantially (by 500%) increased his space use and movements following loss of the female. The other male reduced (by 58%) his space use around the den site where kits were confirmed as being present. Of 2 instances where the remaining pair member was a female, 1 female reduced her space use (by 33%) around a den site before leaving the study area 10 d later. The other female increased her space use (by 42%), but maintained an area that overlapped the spaces maintained formerly by herself and her mate. Our findings suggest that Gray Fox distribution is potentially affected by loss of mates, but that both genders will maintain areas used previous...
Brian L. Cypher - One of the best experts on this subject based on the ideXlab platform.
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relative abundance of endangered san joaquin kit Foxes vulpes macrotis mutica based on scat detection dog surveys
Southwestern Naturalist, 2006Co-Authors: Deborah A. Smith, Katherine Ralls, Brian L. Cypher, Howard O. Clark, Patrick A. Kelly, Daniel F. Williams, Jesús E. MaldonadoAbstract:Abstract Although the San Joaquin kit Fox (Vulpes macrotis mutica) has been a federally protected subspecies since 1967, current information on its status throughout much of its historical range is lacking. Since 1983, only 5 surveys have been conducted, and a recent recovery plan emphasized the need for better information on the status of this subspecies. Between 2001 and 2003, we attempted to obtain new information on this kit Fox on specific public and private properties in 8 counties in the San Joaquin Valley, California, where knowledge of its current status was limited or poorly understood. We used a trained detection-dog to survey for kit Fox, red Fox (V. vulpes), and Gray Fox (Urocyon cinereoargenteus) scats on selected properties, followed by species identification based on genetic analysis of DNA extracted from all scats collected. Despite extensive survey efforts (539 km), kit Fox was only detected in Merced County, in the area of Santa Nella, where a small kit Fox population was previously doc...
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RELATIVE ABUNDANCE OF ENDANGERED SAN JOAQUIN KIT FoxES (VULPES MACROTIS MUTICA) BASED ON SCAT–DETECTION DOG SURVEYS
The Southwestern Naturalist, 2006Co-Authors: Deborah A. Smith, Katherine Ralls, Brian L. Cypher, Howard O. Clark, Patrick A. Kelly, Daniel F. Williams, Jesús E. MaldonadoAbstract:Abstract Although the San Joaquin kit Fox (Vulpes macrotis mutica) has been a federally protected subspecies since 1967, current information on its status throughout much of its historical range is lacking. Since 1983, only 5 surveys have been conducted, and a recent recovery plan emphasized the need for better information on the status of this subspecies. Between 2001 and 2003, we attempted to obtain new information on this kit Fox on specific public and private properties in 8 counties in the San Joaquin Valley, California, where knowledge of its current status was limited or poorly understood. We used a trained detection-dog to survey for kit Fox, red Fox (V. vulpes), and Gray Fox (Urocyon cinereoargenteus) scats on selected properties, followed by species identification based on genetic analysis of DNA extracted from all scats collected. Despite extensive survey efforts (539 km), kit Fox was only detected in Merced County, in the area of Santa Nella, where a small kit Fox population was previously doc...
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Food Item Use by Three Sympatric Canids in Southern Illinois
1993Co-Authors: Brian L. CypherAbstract:I investigated use of food resources among coyotes (Canis latrans), red Foxes (Vulpes vulpes), and Gray Foxes (Urocyon cinereoargenteus) in southern Illinois. All three species used similar food items; coyote and red Fox diets were most similar while coyote and Gray Fox diets were least similar. Gray Fox diets also exhibited greater diversity and omnivory. The high dietary overlap among species results in the potential for resource competition. Competition with coyotes may have reduced red Fox abundance in southern Illinois. Despite competition for food resources, Gray Foxes appear able to coexist with coyotes possibly through habitat segregation and avoidance of antagonistic encounters by climbing trees.
Viorel D. Popescu - One of the best experts on this subject based on the ideXlab platform.
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Relative Importance of Habitat Characteristics and Interspecific Relations in Determining Terrestrial Carnivore Occurrence
Frontiers Media S.A., 2018Co-Authors: Mackenzie Rich, Cassandra Thompson, Suzanne Prange, Viorel D. PopescuAbstract:Carnivores act as top-down regulators in terrestrial ecosystems, and their occurrence and relative abundance is a result of complex interactions between food and habitat availability, human pressure (e.g., trapping, hunting, roadkill), and intraguild interactions (competition, predation). Eastern United States has a long history of human impact, which resulted in an altered carnivore community. Specifically, Ohio presents an interesting case for evaluating the relative roles of interspecific relations and habitat characteristics for shaping the carnivore community, as its carnivore community has a unique dynamics and composition: invasive coyote and red Fox (Vulpes vulpes), and native bobcat (Lynx rufus), currently recovering and expanding its range, Gray Fox (Urocyon cinereoargenteus) declining at a fast pace, and the generalist raccoon (Procyon lotor) and Virginian opossum (Didelphis virginiana). We used 50 camera traps to collect presence/absence data in southeastern Ohio, USA. We hypothesized potential interactions between the six carnivores, and used land cover variables, as well as occupancy probabilities of interacting species, to parameterize to single-species occupancy models. We found that landscape composition at three different scales (500 and 1000 m buffer around camera locations, and 3 × 3 km grid cell) had little effect on species occurrence. We identified strong negative interspecific relations between carnivores, with bobcat occurrence being influenced by presence of coyotes, red Fox occurrence by Gray Foxes, and raccoon occurrence by Virginia possums. While these findings cannot discriminate between habitat partitioning (spatial or temporal) and competition (direct or interference), they lend support to complex dynamics between invasive coyotes and red Foxes and recovering (bobcat) and declining (Gray Fox) native carnivore species. In particular, the negative relation between the apex predator in our system, C. latrans, and L. rufus, raise further questions on whether direct competition from coyotes has the potential to slow bobcat population recovery. In the context of regulated trapping (ongoing for Gray Fox and potential season for bobcat), a better understanding of the carnivore intraguild relations can inform management and conservation actions targeted at minimizing the impact of competition on at-risk native species from non-native species
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Table_1_Relative Importance of Habitat Characteristics and Interspecific Relations in Determining Terrestrial Carnivore Occurrence.pdf
2018Co-Authors: Mackenzie Rich, Cassandra Thompson, Suzanne Prange, Viorel D. PopescuAbstract:Carnivores act as top-down regulators in terrestrial ecosystems, and their occurrence and relative abundance is a result of complex interactions between food and habitat availability, human pressure (e.g., trapping, hunting, roadkill), and intraguild interactions (competition, predation). Eastern United States has a long history of human impact, which resulted in an altered carnivore community. Specifically, Ohio presents an interesting case for evaluating the relative roles of interspecific relations and habitat characteristics for shaping the carnivore community, as its carnivore community has a unique dynamics and composition: invasive coyote and red Fox (Vulpes vulpes), and native bobcat (Lynx rufus), currently recovering and expanding its range, Gray Fox (Urocyon cinereoargenteus) declining at a fast pace, and the generalist raccoon (Procyon lotor) and Virginian opossum (Didelphis virginiana). We used 50 camera traps to collect presence/absence data in southeastern Ohio, USA. We hypothesized potential interactions between the six carnivores, and used land cover variables, as well as occupancy probabilities of interacting species, to parameterize to single-species occupancy models. We found that landscape composition at three different scales (500 and 1000 m buffer around camera locations, and 3 × 3 km grid cell) had little effect on species occurrence. We identified strong negative interspecific relations between carnivores, with bobcat occurrence being influenced by presence of coyotes, red Fox occurrence by Gray Foxes, and raccoon occurrence by Virginia possums. While these findings cannot discriminate between habitat partitioning (spatial or temporal) and competition (direct or interference), they lend support to complex dynamics between invasive coyotes and red Foxes and recovering (bobcat) and declining (Gray Fox) native carnivore species. In particular, the negative relation between the apex predator in our system, C. latrans, and L. rufus, raise further questions on whether direct competition from coyotes has the potential to slow bobcat population recovery. In the context of regulated trapping (ongoing for Gray Fox and potential season for bobcat), a better understanding of the carnivore intraguild relations can inform management and conservation actions targeted at minimizing the impact of competition on at-risk native species from non-native species.
