Determining the Effects of Cattle Grazing Treatments on Yosemite Toads (Anaxyrus [=Bufo] canorus) in Montane Meadows

PLoS One

William E. Frost¹  Kenneth W. Tate²  Leslie M. Roche²  Barbara H. Allen-Diaz³  Susan K. McIlroy³  Rob L. Grasso⁴  Amy J. Lind⁴ 

[1] Agriculture and Natural Resources Research and Extension Centers, Davis, California, United States of America;Department of Plant Sciences, University of California Davis, Davis, California, United States of America;Environmental Science, Policy, and Management Department, University of California, Berkeley, Berkeley, California, United States of America;USDA Forest Service, Pacific Southwest Research Station, Davis, California, United States of America

关键词: Toads;    Grazing;    Livestock;    Tadpoles;    Forests;    Livestock care;    Animal sexual behavior;    Amphibians;   

DOI  :  10.1371/journal.pone.0079263

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

Amphibians are experiencing a precipitous global decline, and population stability on public lands with multiple uses is a key concern for managers. In the Sierra Nevada Mountains (California, USA), managers have specifically identified livestock grazing as an activity that may negatively affect Yosemite toads due to the potential overlap of grazing with toad habitat. Grazing exclusion from Yosemite toad breeding and rearing areas and/or entire meadows have been proposed as possible management actions to alleviate the possible impact of cattle on this species. The primary objective of this study was to determine if different fencing treatments affect Yosemite toad populations. We specifically examined the effect of three fencing treatments on Yosemite toad breeding pool occupancy, tadpoles, and young of the year (YOY). Our hypothesis was that over the course of treatment implementation (2006 through 2010), Yosemite toad breeding pool occupancy and early life stage densities would increase within two fencing treatments relative to actively grazed meadows due to beneficial changes to habitat quality in the absence of grazing. Our results did not support our hypothesis, and showed no benefit to Yosemite toad presence or early life stages in fenced or partially fenced meadows compared to standard USDA Forest Service grazing levels. We found substantial Yosemite toad variation by both meadow and year. This variation was influenced by meadow wetness, with water table depth significant in both the tadpole and YOY models.

【 授权许可】

CC BY