scholarly journals Living in the concrete jungle: carnivore spatial ecology in urban parks

2020 ◽  
Author(s):  
Siria Gámez ◽  
Nyeema C. Harris
Keyword(s):  
Spatial Ecology ◽  
Interspecific Interactions ◽  
Spatial Association ◽  
Occupancy Models ◽  
Urocyon Cinereoargenteus ◽  
Anthropogenic Pressures ◽  
Red Foxes ◽  
Striped Skunk ◽  
Species Occupancy ◽  
Human Shield

ABSTRACTPeople and wildlife are living in an increasingly urban world, replete with unprecedented human densities, sprawling built environments, and altered landscapes. Such anthropogenic pressures can affect multiple processes within an ecological community, from spatial patterns to interspecific interactions. We tested two competing hypotheses, human shields versus human competitors, to characterize how humans affect the carnivore community using multi-species occupancy models. From 2017-2020, we conducted the first camera survey of city parks in Detroit, Michigan, and collected spatial occurrence data of the local native carnivore community. Our 12,106-trap night survey captured detected data for coyotes (Canis latrans), red foxes (Vulpes vulpes), gray foxes (Urocyon cinereoargenteus), raccoons (Procyon lotor), and striped skunks (Mephitis mephitis). Overall occupancy varied across species (Ψcoyote=0.40, Ψ raccoon=0.54, Ψred fox =0.19, Ψstriped skunk =0.09). Contrary to expectations, humans did not significantly affect individual occupancy for these urban carnivores. However, co-occurrence between coyote and skunk only increased with human activity. The observed positive spatial association between an apex and subordinate pair supports the human shield hypothesis. Our findings demonstrate how urban carnivores can exploit spatial refugia and coexist with humans in the cityscape.

Relative abundance of coyotes influences gray fox occupancy across the eastern United States

2020 ◽  
Author(s):  
Michael Egan ◽  
Casey Day ◽  
Todd E Katzner ◽  
Patrick A. Zollner
Keyword(s):  
United States ◽  
Large Scale ◽  
Forest Cover ◽  
Interspecific Interactions ◽  
Single Species ◽  
Camera Trap ◽  
Eastern United States ◽  
Occupancy Models ◽  
Urocyon Cinereoargenteus ◽  
Gray Fox

Gray fox (Urocyon cinereoargenteus Schreber, 1775) populations in portions of the eastern United States have experienced declines whose trajectories differ from those of other mesocarnivore populations. One hypothesis is that gray fox declines may result from interspecific interactions, particularly competition with abundant coyotes (Canis latrans Say, 1823). Alternatively, gray foxes may respond negatively to increased urbanization and reduced forest cover. To evaluate these hypotheses, we used single-species occupancy models of camera trap data to test the effects of habitat covariates, such as the amount of urbanization and forest, on coyote and gray fox occupancy. Additionally, we test the effect of an n-mixture based index of the number of coyotes at each camera trap site on gray fox occupancy. Results indicate that occupancy probabilities of coyote and gray fox relate positively to the amount of forest, but they provided no evidence urban cover impacts gray foxes. Additionally, gray fox occupancy was negatively related to the index of the number of coyotes at each site. Our models support the idea that interactions with coyotes impact gray fox occupancy across the eastern U.S. These results illustrate how large scale studies can relate mechanisms identified within specific landscapes to phenomena observed at larger scales.

scholarly journals Topographic Effects on the Spatial Species Associations in Diverse Heterogeneous Tropical Evergreen Forests

2021 ◽  
Vol 13 (5) ◽  
pp. 2468
Author(s):  
Nguyen Hong Hai ◽  
Yousef Erfanifard ◽  
Van Bac Bui ◽  
Trinh Hien Mai ◽  
Any Mary Petritan ◽  
...  
Keyword(s):  
Species Interactions ◽  
Species Coexistence ◽  
Spatial Scales ◽  
Interspecific Interactions ◽  
Spatial Association ◽  
Topographic Effects ◽  
Habitat Association ◽  
Important Species ◽  
Evergreen Forests ◽  
Partial Overlap

Studying spatial patterns and habitat association of plant communities may provide understanding of the ecological mechanisms and processes that maintain species coexistence. To conduct assessments of correlation between community compositions and habitat association, we used data from two topographically different plots with 2 ha area in tropical evergreen forests with the variables recorded via grid systems of 10 × 10 m subplots in Northern-Central Vietnam. First, we tested the relationship between community composition and species diversity indices considering the topographical variables. We then assessed the interspecific interactions of 20 dominant plant species using the nearest-neighbor distribution function, Dij(r), and Ripley’s K-function, Kij(r). Based on the significant spatial association of species pairs, indices of interspecific interaction were calculated by the quantitative amounts of the summary statistics. The results showed that (i) community compositions were significantly influenced by the topographic variables and (ii) almost 50% significant pairs of species interactions were increased with increasing spatial scales up to 10–15 m, then declined and disappeared at scales of 30–40 m. Segregation and partial overlap were the dominant association types and disappeared at larger spatial scales. Spatial segregation, mixing, and partial overlap revealed the important species interactions in maintaining species coexistence under habitat heterogeneity in diverse forest communities.

A penalized likelihood for multi‐species occupancy models improves predictions of species interactions

Ecology ◽  
2021 ◽  
Author(s):  
Hannah L. Clipp ◽  
Amber L. Evans ◽  
Brin E. Kessinger ◽  
Kenneth Kellner ◽  
Christopher T. Rota
Keyword(s):  
Species Interactions ◽  
Penalized Likelihood ◽  
Occupancy Models ◽  
Species Occupancy

scholarly journals Carnivore distributions across chaparral habitats exposed to wildfire and rural housing in southern California

2014 ◽  
Vol 23 (4) ◽  
pp. 591 ◽  
Author(s):  
P. A. Schuette ◽  
J. E. Diffendorfer ◽  
D. H. Deutschman ◽  
S. Tremor ◽  
W. Spencer
Keyword(s):  
Southern California ◽  
Coastal Sage Scrub ◽  
Lynx Rufus ◽  
Management Policy ◽  
Native Plant ◽  
Anthropogenic Pressures ◽  
Gray Fox ◽  
Striped Skunk ◽  
Occupancy Patterns ◽  
Animal Communities

Chaparral and coastal sage scrub habitats in southern California support biologically diverse plant and animal communities. However, native plant and animal species within these shrubland systems are increasingly exposed to human-caused wildfires and an expansion of the human–wildland interface. Few data exist to evaluate the effects of fire and anthropogenic pressures on plant and animal communities found in these environments. This is particularly true for carnivore communities. To address this knowledge gap, we collected detection–non-detection data with motion-sensor cameras and track plots to measure carnivore occupancy patterns following a large, human-caused wildfire (1134km2) in eastern San Diego County, California, USA, in 2003. Our focal species set included coyote (Canis latrans), gray fox (Urocyon cinereoargenteus), bobcat (Lynx rufus) and striped skunk (Mephitis mephitis). We evaluated the influence on species occupancies of the burned environment (burn edge, burn interior and unburned areas), proximity of rural homes, distance to riparian area and elevation. Gray fox occupancies were the highest overall, followed by striped skunk, coyote and bobcat. The three species considered as habitat and foraging generalists (gray fox, coyote, striped skunk) were common in all conditions. Occupancy patterns were consistent through time for all species except coyote, whose occupancies increased through time. In addition, environmental and anthropogenic variables had weak effects on all four species, and these responses were species-specific. Our results helped to describe a carnivore community exposed to frequent fire and rural human residences, and provide baseline data to inform fire management policy and wildlife management strategies in similar fire-prone ecosystems.

Space fit for a king: spatial ecology of king cobras (Ophiophagus hannah) in Sakaerat Biosphere Reserve, Northeastern Thailand

2019 ◽  
Vol 40 (2) ◽  
pp. 163-178 ◽  
Author(s):  
Benjamin Michael Marshall ◽  
Colin Thomas Strine ◽  
Max Dolton Jones ◽  
Taksin Artchawakom ◽  
Ines Silva ◽  
...  
Keyword(s):  
Habitat Use ◽  
Breeding Season ◽  
Protected Area ◽  
Spatial Ecology ◽  
Radio Telemetry ◽  
Biosphere Reserve ◽  
Adult Males ◽  
Anthropogenic Pressures ◽  
Anthropogenic Landscapes ◽  
Ophiophagus Hannah

Abstract A species’ spatial ecology has direct implications for that species’ conservation. Far-ranging species may be more difficult to conserve because their movements increase their chances of encountering humans. The movements can take them out of protected areas, which is especially risky for species that are routinely persecuted. The king cobra (Ophiophagus hannah), a large venomous elapid, is subject to anthropogenic pressures, such as persecution and habitat loss. Here we present results from a study using radio telemetry to quantify movements and habitat use of nine king cobras in and around a protected area in Northeast Thailand. This study is the first investigation into the movements and habitat use of king cobras outside of the Western Ghats, India. On average, the tracked king cobra’s use areas of 493.42 ± 335.60 ha (95% fixed kernel), moving 183.24 ± 82.63 m per day. King cobras did not remain in intact forested area. Five of the individuals frequently used the human-dominated agricultural areas surrounding the protected area, appearing to make regular use of irrigation canals. Two adult males showed increases in movements during the breeding season. One male’s increased breeding season range caused him to venture beyond the protected area, shifting his habitat use from intact forests to scrub in human-dominated areas. King cobras’ large home range and willingness to use anthropogenic landscapes merits special consideration from conservation planners.

Low Prevalence ofEchinococcus multilocularisin Michigan, U.S.A.: A Survey of Coyotes (Canis latrans), Red Foxes (Vulpes vulpes), and Gray Foxes (Urocyon cinereoargenteus), 2009–2012

2015 ◽  
Vol 82 (2) ◽  
pp. 285-290 ◽  
Author(s):  
Julie R. Melotti ◽  
Patrick M. Muzzall ◽  
Daniel J. O’Brien ◽  
Thomas M. Cooley ◽  
Jean I. Tsao
Keyword(s):  
Vulpes Vulpes ◽  
Canis Latrans ◽  
Urocyon Cinereoargenteus ◽  
Red Foxes ◽  
Low Prevalence

Predicting fish species richness and habitat relationships using Bayesian hierarchical multispecies occupancy models

2020 ◽  
Vol 77 (3) ◽  
pp. 602-610
Author(s):  
Shannon White ◽  
Evan Faulk ◽  
Caleb Tzilkowski ◽  
Andrew Weber ◽  
Matthew Marshall ◽  
...  
Keyword(s):  
Species Richness ◽  
Fish Community ◽  
Fish Assemblages ◽  
Similar Species ◽  
Occupancy Models ◽  
Imperfect Detection ◽  
Modeling Framework ◽  
Bayesian Hierarchical ◽  
Recreation Area ◽  
Species Occupancy

Understanding how stream fishes respond to changes in habitat availability is complicated by low occurrence rates of many species, which in turn reduces the ability to quantify species–habitat relationships and account for imperfect detection in estimates of species richness. Multispecies occupancy models have been used sparingly in the analysis of fisheries data, but address the aforementioned deficiencies by allowing information to be shared among ecologically similar species, thereby enabling species–habitat relationships to be estimated for entire fish communities, including rare species. Here, we highlight the utility of hierarchical multispecies occupancy models for the analysis of fish community data and demonstrate the modeling framework on a stream fish community dataset collected in the Delaware Water Gap National Recreation Area, USA. In particular, we demonstrate the ability of the modeling framework to make inferences at the species-, guild-, and community-levels, thereby making it a powerful tool for understanding and predicting how environmental variables influence species occupancy probabilities and structure fish assemblages.

Model selection and assessment for multi-species occupancy models

Ecology ◽  
2016 ◽  
Vol 97 (7) ◽  
pp. 1759-1770 ◽  
Author(s):  
Kristin M. Broms ◽  
Mevin B. Hooten ◽  
Ryan M. Fitzpatrick
Keyword(s):  
Model Selection ◽  
Occupancy Models ◽  
Species Occupancy ◽  
Selection And Assessment

Morphology and digestive efficiency of red foxes (Vulpes vulpes) and grey foxes (Urocyon cinereoargenteus) in relation to diet

1987 ◽  
Vol 65 (1) ◽  
pp. 72-79 ◽  
Author(s):  
Carolyn Renzulli Jaslow
Keyword(s):  
Vulpes Vulpes ◽  
Red Fox ◽  
Masticatory Muscles ◽  
Moment Arm ◽  
Urocyon Cinereoargenteus ◽  
Digestive Efficiency ◽  
Red Foxes ◽  
Dietary Preference ◽  
Moment Arms ◽  
Resistance Moment

Measurements of the skull and dentition, and digestive efficiency of red foxes (Vulpes vulpes) and grey foxes (Urocyon cinereoargenteus) were compared to determine whether differences in morphology and digestive ability could be associated with dietary preference. The longer jaws of the more carnivorous red fox increase the resistance moment arm when biting at the canines and carnassials, but greater size and mechanical leverage of the masticatory muscles in this species compensate for this, enabling the red fox to bite with forces that should be comparable to or exceed those of the grey fox. The relatively shorter masticatory moment arms of the more omnivorous–insectivorous grey fox should increase bite speed. Both fox species digested mice with equal efficiency, but the more omnivorous grey foxes had higher digestive efficiencies than red foxes when fed a diet of fruit. These morphological and physiological differences observed between sympatric red foxes and grey foxes may allow each species to exploit different foods more effectively.

scholarly journals Designing an occupancy framework to monitor an endemic rainforest duck: Methodological and modelling considerations

2020 ◽  
Author(s):  
Shah Nawaz Jelil ◽  
Murchana Parasar ◽  
Laura Cancino ◽  
Kimberly Cook
Keyword(s):  
Detection Probability ◽  
Site Occupancy ◽  
Optimal Number ◽  
Occupancy Models ◽  
Occupancy Detection ◽  
Habitat Factors ◽  
Long Term Ecological Research ◽  
Species Occupancy ◽  
Future Population

AbstractUnderstanding species trend, decline or growth, is vital to further conservation efforts. Species-habitat relationship studies are equally important for conservation as it helps in understanding the habitat a particular species depends upon, i.e. habitat conservation. However, rare and endemic species are inherently difficult to study and occupancy models are especially useful in such cases. We conducted the first detection, non-detection survey for the white winged duck in Dehing Patkai Wildlife Sanctuary, India to assess site occupancy and test habitat factors that explain its occupancy. We found that white winged duck occupancy was low (0.27 ± 0.21 SE) and detection probability was 0.44 ± 0.30 SE. We found that increasing tree richness and decreasing elevation increased species occupancy. Detection probability was influenced by our effort in that detection increased with increasing number of survey hours. Using two standard approaches, we estimated the optimal number of sites and replicate surveys for future occupancy studies. We further present considerations for future surveys. Considering the sporadic and fragmented information available, we recommend long-term ecological research to better understand the present and future population trends of the species.

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