Boreal toads (Bufo boreas boreas) were once considered widely distributed and common
amphibians in the western United States. The boreal toad shows signs of significant declines in
population size and distribution across its range in western North America, and especially in the
southern Rocky Mountains (Wyoming, Colorado, and New Mexico) (Corn et al 1989, Carey 1993,
Corn 1994, Keinath and Bennet 2000, BTRT 2001). The Southern Rocky Mountain Population of
boreal toads was petitioned for federal listing with the U.S. Fish and Wildlife Service in 1995 and
was classified as warranted but precluded (USDI Fish and Wildlife Service 1995). The boreal
toad has been listed as endangered by the state of New Mexico since 1976 (New Mexico Stat.
Ann. §§ 17-2-37 et seq) (NMGFD 1988) and Colorado since 1993 (Colorado Rev. Stat. Ann.
§§33-2-109 et seq) (CDOW 2000). The Wyoming Game and Fish Department ranks the southern
Rocky Mountain population of the boreal toad as a native species of special concern 1 (NSS1),
and the northern Rocky Mountain population as NSS2 (Oakleaf et al. 2002).
This assessment of the boreal toad is part of the Species Conservation Assessment Project for
the Wyoming Office of the USDI Bureau of Land Management (BLM). It addresses the biology,
ecology, and conservation status of the boreal toad throughout its current range in Wyoming and
North America. Our goal is to provide a current summary of published information and expert
interpretation of this information that can be used to develop management plans.
The boreal toad was selected for this assessment because it is classified as a sensitive species
by the BLM in Wyoming due to recently observed declines in abundance and distribution across
its range in the Rocky Mountains. The boreal toad was once considered widespread and common
throughout its range but it has declined dramatically over the past 20 years (BTRT 2001)