By Elizabeth J. Axley
Geographic Range
The range of Great Plains toads stretches from extreme southwest Manitoba, Canada, to southeast Alberta, Canada, and south to Texas; eastern-central Utah to extreme southeast California and far south into Chihuahua, Coahuila, Durango, and San Luis Potosi, Mexico. There is a disjunct colony of Great Plains toads in south-central Colorado.
Habitat
Great Plains toads are common toads of the great open spaces of broad grasslands, and the arid southwest. They are usually found in the lower, damper sections of these areas. These toads frequent irrigation canals, flood plains of rivers, temporary rain pools, and reservoirs.
These animals are found in the following types of habitat:
temperate 
; terrestrial .
Terrestrial Biomes:
desert or dune ; savanna or grassland .
Aquatic Biomes:
rivers and streams; temporary pools.
Other:
agricultural ; riparian .
Physical Description
The adult Great Plains toad averages 4.8-9 cm in length. On its back it has large dark blotches. Each blotch is boldly bordered by light pigment and contains many warts. The colors of this toad are generally yellowish, brown, greenish, or gray on top. Below is unspotted, cream to white, with a yellow or orange-yellow seat patch. Some specimens have been found with a narrow, light mid dorsal stripe. The head of the Great Plains toad is relatively small with a well-developed cranial crest. Their snout is blunt and rounded.
Reproduction
The Great Plains toad breeds only after rain storms in spring and summer when the temperature exceeds 12 degrees C. Breeding sites are restricted to relatively clear shallow water, which include buffalo wallows, flooded fields, and the edges of extensive temporary pools. They breed usually in large congresses built up by the reaction of males to one another's call. A calling male clutches any toad that happens to touch him, and once a female is clasped she is retained tenaciously. A single female may lay as many as 20,000 eggs, which are attached to debris near the bottom of temporary pools, permanent springs, and small streams. Roughly two days after laying the eggs hatch. The tadpoles are small when first hatched and grow only to about 25 mm in length. About 1 1/2 months after the eggs are laid, metamorphosis begins and takes less than two weeks to complete. The newly transformed young of the year will not become sexually mature until they are 3-5 years old.
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (external ); oviparous .
Behavior
This species spends a considerable amount of time underground, because the period favorable for activity may last only a few weeks in the spring or summer. The toads burrow by backing into the ground with a shuffling movement of the hind feet. The Great Plains toad is nocturnal but sometimes diurnal, especially during the breeding period. Usually, however, they come out of their burrows about an hour before dusk. When annoyed this toad may assume a defensive attitude common to many anurans. The lungs are inflated, thereby increasing the size of the body; the head is lowered and the eyes are often depressed into their sockets.
Food Habits
The Great Plains toad is an insectivore with a diet that includes, moths, flies, cutworms and beetles. Of its prey, cutworms pose the biggest problem to humans. This toad is known to be important to agriculture because they eat cutworms and many other noxious insects that feed on and damage crops. The Great Plains toad is nocturnal, thus feeds at night, which makes it hard to observe their food habits.
Economic Importance for Humans: Positive
The Great Plains toad is an effective enemy of over-wintering cutworms in Oklahoma. Their value to agriculture on a yearly basis in Oklahoma has been estimated at $25 per individual toad.
Conservation Status
In order to protect this species its natural habitat must be protected. In many states in the Great Plains region there are laws in place that protect the plains. To ensure the continued survival of this species this protection of habitat must continue.
For More Information
Find Bufo cognatus information at
Contributors
Elizabeth J. Axley (author), University of Michigan.
