title: Effects of a protection gradient on carnivore density and survival: an example with leopards in the Luangwa valley, Zambia.
abstract: Human activities on the periphery of protected areas can limit carnivore populations, but measurements of the strength of such effects are limited, largely due to difficulties of obtaining precise data on population density and survival. We measured how density and survival rates of a previously unstudied leopard population varied across a gradient of protection and evaluated which anthropogenic activities accounted for observed patterns. Insights into this generalist's response to human encroachment are likely to identify limiting factors for other sympatric carnivore species. Motion-sensitive cameras were deployed systematically in adjacent, similarly sized, and ecologically similar study areas inside and outside Zambia's South Luangwa National Park (SLNP) from 2012 to 2014. The sites differed primarily in the degree of human impacts: SLNP is strictly protected, but the adjacent area was subject to human encroachment and bushmeat poaching throughout the study, and trophy hunting of leopards prior to 2012. We used photographic capture histories with robust design capture-recapture models to estimate population size and sex-specific survival rates for the two areas. Leopard density within SLNP was 67% greater than in the adjacent area, but annual survival rates and sex ratios did not detectably differ between the sites. Prior research indicated that wire-snare occurrence was 5.2 times greater in the areas adjacent to the park. These results suggest that the low density of leopards on the periphery of SLNP is better explained by prey depletion, rather than by direct anthropogenic mortality. Long-term spatial data from concurrent lion studies suggested that interspecific competition did not produce the observed patterns. Large carnivore populations are often limited by human activities, but science-based management policies depend on methods to rigorously and quantitatively assess threats to populations of concern. Using noninvasive robust design capture-recapture methods, we systematically assessed leopard density and survival across a protection gradient and identified bushmeat poaching as the likely limiting factor. This approach is of broad value to evaluate the impacts of anthropogenic activities on carnivore populations that are distributed across gradients of protection.
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.|Department of Ecology Montana State University Bozeman Montana 59717.
authors.forename: Elias
authors.initials: E
authors.lastname: Rosenblatt
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.|Department of Ecology Montana State University Bozeman Montana 59717.
authors.forename: Scott
authors.initials: S
authors.lastname: Creel
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.|Department of Ecology Montana State University Bozeman Montana 59717.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Becker
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.
authors.forename: Johnathan
authors.initials: J
authors.lastname: Merkle
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.
authors.forename: Henry
authors.initials: H
authors.lastname: Mwape
authors.affiliation: Zambian Carnivore Programme PO Box 80 Mfuwe Eastern Province Zambia.|University of Alaska Anchorage Alaska Center for Conservation Science 3211 Providence Drive Anchorage Alaska 99508.
authors.forename: Paul
authors.initials: P
authors.lastname: Schuette
authors.affiliation: Department of National Parks and Wildlife Private Bag 1 Kafue Road Chilanga Zambia.
authors.forename: Twakundine
authors.initials: T
authors.lastname: Simpamba
keywords: Anthropogenic effects; Panthera pardus; bushmeat; harvest; leopard; prey depletion; robust design