Protecting and enhancing the natural values of Salt Spring Island and its surrounding waters

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Western Toad

Western Toad, Anaxyrus boreas

Western Toad, Anaxyrus (formerly Bufo) boreas, breeds in ponds, slow portions of streams, and shallow edges of lakes with sandy bottoms. When not breeding, the toads occur in wetlands, meadows, or forest, where they shelter under decaying logs, in rodent burrows, or within loose soil. Sometimes they are found far from water. The Western Toad is readily identified by its dry, warty skin and a pronounced, oval poison gland (parotoid gland) on each cheek behind the eye. The colour of the back and sides is variable, ranging from greenish to tan, brown, grey, or black, and may be mottled. Raised poison glands (“warts”) on the body are often reddish brown and surrounded by a dark ring. A whitish line along the mid-back is diagnostic but may be indistinct or lacking in newly metamorphosed toadlets. The underside is light with darker flecks. Adults range from about 60 to 125 mm in body length, females being larger, and metamorphs from 6 to 13 mm.  Eggs are laid when the water starts warming up, usually in May in our area. They are in long strings, often entwined with each other and within submerged vegetation. Individual eggs are small (1.5 mm in diameter) and black. Breeding areas tend to receive traditional use, and females typically deposit their eggs communally, on top of each other, forming huge masses that may contain hundreds of thousands of eggs. Tadpoles are small, up to about 25 mm in body length. The body and tail musculature are jet black, and the rounded tail fin is translucent with black flecking. Tadpoles tend to school and often form large, dense aggregations in shallow warm water.

2016-12-13T10:36:09+00:00