Western Toad (Bufo boreas) 



Description: Adults have dry skin with small warts, and are gray, brown, or olive-green with a 

 prominent white or yellowish line down the center of the back; very young transformed toads 

 typically lack the dorsal line, and the warts are often red-brown in color. The adult has a 

 snout- vent length of 2.5-5". This is the only toad in northwestern Montana but can be 

 distinguished from toads in other areas of Montana by: 1) a cranial crest faint or absent; 2) 

 oval parotoid glands; 3) two tubercles on the sole of the hind feet; and 3) a horizontal pupil. 

 Tadpoles are typically jet black, while all the Montana frog species tadpoles are green or 

 bronze. Eggs are laid in long, clear, double strings, and each has a black embryo. 



Habitat and Habits: Adults are largely terrestrial and found in a variety of habitats from valley 

 bottoms to high elevations; they breed in lakes, ponds, and slow streams with a preference for 

 shallow areas with mud bottoms. Breeding and egg laying in northwestern Montana usually 

 takes place a month after snow-melt, from April at lower elevations to July at higher sites. 

 We found eggs as early as 30 May 93 in a backwater of the Yaak River and as late as 20 June 

 94 at Blue Lake. Tadpoles were seen 30 May 93 at Horse lake ponds and as late as 10 

 September 94 with emerging toadlets at Vinal Lake. The earliest emerging toadlets were 

 seen on 14 July 94 at Flower Lake. Tadpoles typically take 2-3 months to metamorphose in 

 Montana, depending on water temperature (Black 1970b). At metamorphosis, hundreds of 

 small toads, many with the tails still present, can be found on the shores of breeding ponds. 



Surveying: Tadpoles are seen in ponds during the day and can be sampled with a dipnet. During 

 the breeding season, adults may be seen in the water but otherwise they are found in more 

 terrestrial habitats. 



Status: Tadpoles and eggs of the Western toad were observed at only 10 sites during the 1993-94 

 survey in the KNF. No toad reproductive effort was seen in either the Cabinet or Fortine 

 districts although some probably existed. Adults were encountered occasionally away from 

 the breeding sites, but the paucity of reproductive effort is of concern. The US Fish and 

 Wildlife Service has received a petition to list this species range-wide. Declines have 

 recently been recorded in Yellowstone National Park (Peterson et al. 1992), Wyoming, and 

 Colorado (Carey 1993). We would recommend that a monitoring program be set up for this 

 species. 



Montana Natural Heritage Program rank: G4 S4. 



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