Western toad (Bufo boreas) COSEWIC assessment and status report: chapter 11
Evaluation
Western toad populations found within the Georgia Depression of south-coastal B.C. should be considered a special concern. All recent surveys in this area have yielded low encounter rates of Western Toads compared to historical figures. On Vancouver Island, the local extirpation of one extensive population has been confirmed. Populations in the Georgia Depression are generally isolated from one another, and from other mainland populations as a result of fragmentation and habitat loss. Without immigration of individuals, population viability is improbable. The severe and rapid Western Toad declines witnessed in the United States in recent decades demonstrates the vulnerability of this widespread and common species. The lack of information on population dynamics and the absence of long-term data sets in Canada contribute to an elevated concern for the species in this region. Base on current abundance and distribution information, B. boreas appears not to be at risk of extinction throughout the remainder of its range within Canada at this time. In some areas, it may be the most abundant amphibian species. This status should be re-examined regularly, however, given that declines can happen so rapidly.
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