Anaxyrus nelsoni is an olive-colored toad with a stripe down its back. It is speckled with black and copper-colored spots, and the entire body is covered in warts. Body size ranges from 2-4.4 inches.
Distribution and Habitat
Country distribution from AmphibiaWeb's database: United States
U.S. state distribution from AmphibiaWeb's database: Nevada
A. nelsoni is native to Oasis Valley, in Ney County Nevada and usually resides in diminished desert wetlands and riverine backwaters. In 2002, the total range of A. nelsoni was limited to 12 miles.
Life History, Abundance, Activity, and Special Behaviors
Breeding season occurs in March and April. Eggs can be found in shallow water with little to no plant cover. The eggs hatch in late July and tadpoles metamorphose in early November.
Trends and Threats
Breeding habitat loss is the largest threat to Anaxyrus nelsoni. Unchecked cattail and rush growth, introduction of bullfrogs and crayfish, and river overuse/receiving very little water have contributed to the decline of this species. Conservation measures have been in effect since 1994, when it was discovered that only 32 adult toads remained near the Amargosa River. Since then, volunteers have been able to prevent this species from going extinct, by monitoring growth and maintaining habitat for the toad.
Possible reasons for amphibian decline
General habitat alteration and loss
Predators (natural or introduced)
Written by Prathna Mehta (p_mehta AT berkeley.edu), UC Berkeley URAP
First submitted 2005-02-14
Edited by Tate Tunstall, Kellie Whittaker (2012-08-01)
Species Account Citation: AmphibiaWeb 2012 Anaxyrus nelsoni: Amargosa Toad <http://amphibiaweb.org/species/6057> University of California, Berkeley, CA, USA. Accessed Mar 22, 2018.
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Citation: AmphibiaWeb. 2018. <http://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Mar 2018.
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