Severe mortality of a population of threatened Agassiz’s desert tortoises: the American badger as a potential predator

Endangered Species Research
By: , and 

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Abstract

In the Mojave Desert of the southwestern United States, adult Agassiz’s desert tortoises Gopherus agassizii typically experience high survival, but population declines associated with anthropogenic impacts led to their listing as a threatened Species under the US Endangered Species Act in 1990. Predation of adult tortoises is not often considered a significant threat as they are adapted to deter most predation attempts. Despite these adaptations, some populations have experienced elevated mortality attributed to predators, suggesting that predation pressure may occasionally increase. During the tortoise activity seasons of 2012 and 2013, we observed unsustainably high mortality in 1 of 4 populations of adult desert tortoises (22 and 84%, respectively) in the western Mojave Desert in the vicinity of Barstow, CA. Photographic evidence from trail cameras and examination of carcass condition suggest that American badgers Taxidea taxus— a sometimes cited but unconfirmed predator of adult tortoises — may have been responsible for some of the mortality observed. We discuss the American badger as a plausible predator of a local tortoise population, but recommend further investigation into these events and the impacts such mortality can have on tortoise persistence.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Severe mortality of a population of threatened Agassiz’s desert tortoises: the American badger as a potential predator
Series title Endangered Species Research
DOI 10.3354/esr00680
Volume 28
Year Published 2015
Language English
Publisher Inter-Research
Publisher location Oldendorf, Germany
Contributing office(s) Western Ecological Research Center
Description 8 p.
First page 109
Last page 116
Online Only (Y/N) N
Additional Online Files (Y/N) N