Species Fact Profile: Wyoming Toad (Anaxyrus baxteri)

 Wyoming Toad

Anaxyrus baxteri (Porter, 1968)

Range: Laramie Plains - Wyoming (Historic)

Habitat: Shortgrass Flood Plains, Ponds, Small Lakes

Diet: Ants, Beetles, Worms, and other invertebrates

Social Grouping: Asocial, Breeding Congregations

Reproduction: Males attract females to breeding ponds with their calls.  Eggs are laid from mid-May through early June in gelatinous strings.  Tadpoles hatch shortly after and complete metamorphosis by mid-July

Lifespan: 8 Years

Conservation Status: IUCN Extinct in the Wild

• Body length averages 5-6 centimeters, weigh 55-85 grams, with females growing slightly larger than the males.  The body is covered with small, rounded warts.
• Background color is dark brown, gray, or green, with small dark blotches.  Some individuals have lighter-colored stripes.  The ventral surface is a pale color with spotting.  Males have a darker throat than females
• Spend the cooler parts of the year hibernating, emerging shortly before breeding season (in May or June), when the daytime temperatures reach 70 degrees Fahrenheit.  Rely on rodent burrows as hibernation sites
• Primarily active at night.  Has poor vision - detects its prey by keying in one movement
• Previously listed as a subspecies of Canadian toad (A. hemiophrys)
• Once common, populations crashed in the 1970's, first listed as endangered in 1984.  Cause is unknown, but possible causes include pesticide spraying, habitat loss (very specific habitat requirements, intolerant of disturbance), and climate change.  They are extremely susceptible to the chytrid fungus, which has proven a challenge for captive breeding programs
• A reintroduction program is underway, with some evidence of sustainable reproduction in the wild taking place