Amargosa Toad, Anaxyrus nelsoni survey results & conservation activities within the Oasis Valley, Nye County, Nevada

Authors: Kevin Guadalupe, Brandon Senger, Ron Kegerries, Ron Rogers, Brandon Albrecht, Jef Jaeger

Year: 2023

Abstract

To successfully manage the Amargosa Toad, Anaxyrus nelsoni, it is critical to understand population demographics, habitat, and distribution of the species. Nocturnal mark-recapture surveys for Amargosa Toad in the Oasis Valley were conducted annually starting in 1998, resulting in over 15,000 encounters. The use of passive integrated transponders (PIT tags) allowed long-term assessments of individual movements. Program MARK was used to calculate population and survival estimates. Surveys combined the efforts of state and federal agency personnel, university staff, volunteers, and residents of Beatty, NV. Local participation was critical in allowing access to privately owned land containing previously unknown toad distributions. Information collected to date supports the cooperative efforts of the Amargosa Toad Working Group tasked with implementing a Conservation Agreement Strategy. Findings indicate a large, persistent metapopulation of toads and a U.S. Fish and Wildlife Service review found that the Amargosa Toad was not warranted for federal listing. Following the listing decision, access to private lands increased in the upper Amargosa River drainage, resulting in the documented range of the Amargosa Toad being expanded, along with and other aquatic endemics with conservation opportunity. Contact – kguadalupe@ndow.org