Use of spatial capture–recapture to estimate density of Andean bears in northern Ecuador

@article{Molina2017UseOS,
  title={Use of spatial capture–recapture to estimate density of Andean bears in northern Ecuador},
  author={S. Molina and Angela K Fuller and Dana Morin and J. Andrew Royle},
  journal={Ursus},
  year={2017},
  volume={28},
  pages={117 - 126}
}
Abstract The Andean bear (Tremarctos ornatus) is the only extant species of bear in South America and is considered threatened across its range and endangered in Ecuador. Habitat loss and fragmentation is considered a critical threat to the species, and there is a lack of knowledge regarding its distribution and abundance. The species is thought to occur at low densities, making field studies designed to estimate abundance or density challenging. We conducted a pilot camera-trap study to… Expand
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Abstract Global declines in large-bodied terrestrial vertebrates are widely linked to human disturbance and habitat loss. Identifying remaining opportunities to conserve areas wherein such speciesExpand
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Tremarctos ornatus (Carnivora: Ursidae)
Abstract: Tremarctos ornatus (F.G. Cuvier, 1825) is a tremarctine bear commonly known as the Andean bear. It is a medium-sized bear with black to dark red-brown pelage with dense, long, coarse fur;Expand
Spatial Capture-Recapture for Categorically Marked Populations with An Application to Genetic Capture-Recapture
TLDR
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TLDR
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References

SHOWING 1-10 OF 33 REFERENCES
A preliminary density estimate for Andean bear using camera-trapping methods
Abstract Andean (spectacled) bears (Tremarctos ornatus) are threatened across most of their range in the Andes. To date no field-based density estimations are available for this species. We present aExpand
Andean bear density and abundance estimates — How reliable and useful are they?
Abstract Few attempts have been made to estimate numbers and densities of Andean bears (Tremarctos ornatus). It is understandable that the many challenges involved in these efforts have made itExpand
Estimating population density and connectivity of American mink using spatial capture-recapture.
TLDR
An application of using capture-recapture to develop a model of animal density using a least-cost path model for individual encounter probability that accounts for non-Euclidean connectivity in a highly structured network is demonstrated. Expand
STATUS OF WILD ANDEAN BEARS AND POLICIES FOR THEIR MANAGEMENT
No reliable estimates exist for populations of Andean bears (Tremarctos omatus). They occupy >260,000 km2 in 5 Andean countries, and if their densities are comparable to those of North American blackExpand
Delineating priority habitat areas for the conservation of Andean bears in northern Ecuador
Abstract We sought to identify priority areas for the conservation of Andean bear (Tremarctos ornatus) habitat in the northern portion of the eastern Andean cordillera in Ecuador. The study areaExpand
Density estimation of Asian bears using photographic capture–recapture sampling based on chest marks
Abstract Assessing the conservation status of species of concern is greatly aided by unbiased estimates of population size. Population size is one of the primary parameters determining urgency ofExpand
Food habits of Andean bears in the Oyacachi River Basin, Ecuador
TLDR
Improved the knowledge of the ecology of this species in Ecuador was improved by examining Andean bear diets in the Oyacachi area and the habitats that provide those foods. Expand
Spatial Capture–Recapture: A Promising Method for Analyzing Data Collected Using Artificial Cover Objects
TLDR
It is demonstrated the utility of the application of SCR for studies of reptiles and amphibians by analyzing capture–recapture data from Red-Backed Salamanders, Plethodon cinereus, collected using artificial cover boards. Expand
Andean bear home ranges in the Intag region, Ecuador
TLDR
All bears in this study showed some degree of home range overlap, indicating intra-specific tolerance, and k-NNCH analysis was considered the best method for estimating Andean bear home ranges in fragmented landscapes such as those across the study site. Expand
Andean bear–livestock conflicts: a review
Abstract We review the state of knowledge regarding conflicts between the Andean bear (Tremarctos ornatus) and livestock. Information was gathered from the current known geographic range of theExpand
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