Do protection gradients explain patterns in herbivore densities? An example with ungulates in Zambia’s Luangwa Valley


Autoři: Elias Rosenblatt aff001;  Scott Creel aff001;  Paul Schuette aff001;  Matthew S. Becker aff001;  David Christianson aff001;  Egil Dröge aff005;  Thandiwe Mweetwa aff001;  Henry Mwape aff001;  Johnathan Merkle aff001;  Jassiel M’soka aff001;  Jones Masonde aff006;  Twakundine Simpamba aff006
Působiště autorů: Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia aff001;  Department of Ecology, Montana State University, Bozeman, Montana, United States of America aff002;  Alaska Center for Conservation Science, University of Alaska Anchorage, Anchorage, Alaska, United States of America aff003;  School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America aff004;  Wildlife Conservation Research Unit, University of Oxford, Tubney, United Kingdom aff005;  Department of National Parks and Wildlife, Chilanga, Zambia aff006
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224438

Souhrn

Ungulate populations face declines across the globe, and populations are commonly conserved by using protected areas. However, assessing the effectiveness of protected areas in conserving ungulate populations has remained difficult. Using herd size data from four years of line transect surveys and distance sampling models, we modeled population densities of four important herbivore species across a gradient of protection on the edge of Zambia’s South Luangwa National Park (SLNP) while accounting for the role of various ecological and anthropogenic variables. Our goal was to test whether protection was responsible for density dynamics in this protection gradient, and whether a hunting moratorium impacted herbivore densities during the studies. For all four species, we estimated lower densities in partially protected buffer areas adjacent to SLNP (ranging from 4.5-fold to 13.2-fold lower) compared to protected parklands. Density trends through the study period were species-specific, with some species increasing, decreasing, or remaining stable in all or some regions of the protection gradient. Surprisingly, when controlling for other covariates, we found that these observed differences were not always detectably related to the level of protection or year. Our findings highlight the importance of accounting for variables beyond strata of interest in evaluating the effectiveness of a protected area. This study highlights the importance of comprehensively modeling ungulate population density across protection gradients, identifies lands within an important protection gradient for targeted conservation and monitoring, documents prey depletion and expands our understanding on the drivers in a critical buffer area in Zambia.

Klíčová slova:

Conservation science – Grasses – Herbivory – Lagoons – Population density – Surface water – Wildlife – Zebras


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2019 Číslo 10