Western Toad (Anaxyrus boreas)

Western Toad adult (copyright Stephen Nyman)
Western Toad Adult (copyright Stephen Nyman)

Background: This species is declining severely in Whatcom County and throughout the Puget Lowlands. Once one of the most common amphibian species in the region, sightings of western toads in the lowlands are now rare.  Populations appear to be holding steady in the foothills and higher elevations; however, data supporting these observations are lacking. Western toad is currently a Candidate Species for listing by Washington State and federal “Species of Concern”. Populations of western toad in the Southern Rockies, where they are referred to as “boreal toad,” may be listed under the federal Endangered Species Act.

Adult and Juvenile Description: Adults have a wide body with short legs. They come in a variety of colors with brown and olive green most common. The skin is dry and bumpy with “warts”. A large parotoid gland is located behind each eye. The hind feet are oval and have two large knobs on the heel for digging. The call is a quiet bird-like twittering that is barely audible unless there are a congregation (or knot) of toads at a breeding site.

Larval Description: Tadpoles have square snouts that jut forwards from the round body outline. The tail is not much longer than the body. the dorsal fin is low, and starts at the base of the tail trunk. Tadpoles are black or charcoal-colored. The underside may be slightly paler, but the tail trunk is uniformly dark. The dorsal fin is dark, translucent and densely specked grey or black.

Egg Description: Toad eggs look like a long gelatinous necklace. The eggs are evenly spaced in single file in a very long string of jelly. Many females lay their eggs loosely intertwined creating an extensive mat. Individual eggs are black above and white below.

Habitat: This species occurs in a variety of forested, brush and mountain meadow areas. They breed in ponds, shallow lakes, or side channels of rivers. Eggs are laid in mid spring and deposited on the bottom in water less than 0.5 meters deep. Hatchlings and tadpoles live in the warmest, shallowest water available. Toadlets often move in mass after metamorphosis and these armies can be found crossing county roads.

Information Source: Corkran and Thoms, 1996; WDFW PHS on line: http://wdfw.wa.gov/conservation/phs/list/

Locations in Whatcom County: Silver Lake

For more information on the Western Toad:

Washington Herp Atlas


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