Great plains toad (Bufo cognatus)

Description
Great plains toad

Size

  • Size ranges in length from 45 to 110 millimetres (about 2 to 4.5 inches)

Appearance

  • Covered in dark blotches, each of which contain small warts, on a background of pale brownish-grey or olive.
  • Belly is whitish and without spots.
  • Can be identified by its cranial crests. The crests are quite obvious, starting at the snout and diverging behind the eyes.
  • Tends to lower its head when threatened.

Voice/call

  • Male breeding call is a rapidly repeated, harsh, metallic-sounding trill that can extend for up to 50 seconds. The call is extremely loud at close range and can be heard over one kilometre (a little over a half mile) away.
Distribution
Great Plains toad distribution in Alberta
  • This toad is rarely seen in Alberta, where it exists at the northernmost part of its range.
  • Restricted to short-grass prairie environments; most sightings are from the South Saskatchewan River and its tributaries.
  • Also found in the extreme southwest corner of Saskatchewan.
Natural History

Habitat

  • Although primarily nocturnal, sometimes forages on cloudy, rainy days.
  • Prefers habitats with loose soil to allow burrowing, which it does to avoid high temperatures.

Food

  • Prey items include:
    • beetles
    • cutworms
    • flies
    • moths

When Active

  • Active from April to September in Alberta.
  • Because Great Plains toads are primarily nocturnal, they are difficult to locate outside of the breeding season.
Reproduction and Growth
Life Stage Apr May Jun Jul Aug Sep
Breeding Breeding Bar: April 10 to June 17
Eggs Hatch Eggs Hatch Bar: April 21 to June 27
Transformation Transformation Bar: June 1 to August 13

Breeding behavior

  • In the spring, adults will congregate at breeding ponds and begin calling, but only if conditions are moist enough.
  • After spring or summer rains, breeding occurs in temporary ponds, ditches or almost any flooded area.
  • Prefers to breed in clear, shallow water; will not breed in muddy water.
  • Males congregate in breeding ponds and begin calling. The sound is quite loud and can carry up to 2 kilometres (about 1.24 miles) on the prairies.
  • Long strings of up to 20,000 eggs may be laid by a single female. Egg strings are generally attached to debris on the bottom of the pool of water.
  • The eggs hatch roughly two days later.

Appearance of young

  • Tadpoles are small when first hatched and grow only to about 25 millimetres (about 1 inch) long before transforming in about six weeks time.
  • Although the back may be a mottled brown and grey or black, the tadpoles have a light green underside.

Growth process

  • Newly transformed young of the year will not become sexually mature until they are three to five years old.
Conservation and Management

Status

The Great Plains toad is classified as May Be at Risk in the current Status of Alberta Wildlife report. See the Status of the Great Plains Toad in Alberta report at:

In a subsequent detailed status assessment, Alberta's Endangered Species Conservation Committee identified the Great Plains toad as a Species of Special Concern—a species that without human intervention may soon become threatened with extinction. See information on the Endangered Species Conservation Committee and Species of Special Concern at:

Issues

  • Habitat is threatened by drought and human activity.
  • Recent research indicates there may be more than 2,100 and fewer than 10,000 adults in the province.

Current management

  • Amphibian Monitoring in Alberta

    The Great Plains toad is being monitored under the Alberta Volunteer Amphibian Monitoring Program (AVAMP) and the Researching Amphibian Numbers in Alberta (RANA) program.
  • Multiple Species at Risk (MULTISAR) program

    The Great Plains toad is a focal species of the MULTISAR (multiple species at risk) program. Key elements of the program include:
    • Surveying local populations
    • Assessing the ecological status of the habitat
    • Developing management recommendations and habitat enhancement projects
    • Monitoring the species' response over time
      MULTISAR strives to conserve multiple species at risk by working cooperatively with landowners and lease holders to implement voluntary beneficial management practices on native prairie habitat.
Similar Species
  • Canadian Toad
    The Canadian toad also has prominent cranial crests, but these tend to be parallel or joined at the back.
  • Western Toad
    The Great Plains toad is slightly smaller than the western toad. Like the western toad, it will inflate itself if threatened and raise itself on its legs.
Related links
  • Amphibians
    Learn about Alberta's amphibians, their biology and how to identify various species. Also learn about the global decline of amphibian species, and efforts made to monitor and conserve them.
  • Toads
    Find out about the common traits of toads, and about the different toad species found in Alberta.

 

Page Information

Updated: Dec 19, 2016