sign in sign up
<<
Home , American toad, Canadian toad

’s Species At Risk

Threatened Great Plains cognatus

he Great Plains toad (Bufo cognatus) is a Life History provincially Threatened found T Breeding activity is triggered by warm, in grasslands and dry brushy areas of the heavy rains in late spring or early summer. central plains, from southern Canada to Any native Manitoba species In dry years, breeding may not occur. They central Mexico. It is a relatively large toad, likely to become endangered or often form large assemblages built up by with a body length of up to 11 cm (4 inches). at risk due to low or declining the reaction of males to one another's call. Its upper side ranges in colour from greyish- Males and females may move several numbers in Manitoba if the yellow to light brown or green. It is covered hundred metres to join such an assemblage. factors affecting it don’t with small tubercles or warts and large dark A calling male will clutch any toad that improve. Threatened species brown to olive blotches with well-defined touches him, and once a female is clasped are declared as such by white borders. Its underside is cream- she is held until egg laying is completed up regulation under the coloured, usually with no markings. to 24 hours later. The male gathers the eggs Endangered Species Act. Breeding males have a black, sausage-shaped as they are laid and fertilizes them before vocal sac that is covered by a flap of lighter they are released. Eggs are deposited on coloured skin. It extends above and beyond debris and vegetation near the bottom of the snout when they call. Breeding calls are the pool, where they hatch in one to five loud, pulsating trills that last from five to 50 days, depending on temperature. seconds. The call is described as sounding Newly hatched larvae, or tadpoles, are metallic, mechanical or riveting and similar black, and grow to a length of 11 to 25 mm to a loud hydro transmission line. The Great (0.5 to 1 inch) before they transform into Plains toad is similar in appearance to adult 18 to 49 days after hatching, the more common (Bufo depending on temperature. Many tadpoles americanus) and (Bufo perish due to predation, competition hemiophrys). The Great Plains toad however, for food, and pools drying up prior to is larger in size, and has the large, light- transformation. Young toads are able to bordered dark blotches and a V-shaped reproduce when they are three to five cranial ridge that extends from behind the years old. eyes and converges to form a boss, or a bump, on the snout. Great Plains toads eat flying insects, cutworms, , and . Habitat Tadpoles eat algae, suspended matter, Great Plains toads are generally found in dry, organic debris and plant tissue. Adults open grasslands. They require soft ground to are active mainly at night, especially in burrow into during cold or dry periods. They extended hot or dry periods. They spend breed primarily in temporary wetlands that the daytime under rocks, buried in the mud only contain water in years with heavy spring or hidden in the shade. In winter, they are or early summer rains. The edges of some inactive, burrowing below the frost line. permanent or semi-permanent wetlands may They burrow by backing into the ground also be used. These shallow, clear pools are using a shuffling motion, and are aided often in imperfectly drained, sandy areas in by a tough spade-like projection on their grasslands, pastures, ditches or agricultural hind feet. fields and range in size from large wetlands Distribution to small puddles. The Great Plains toad is found from southern Manitoba, Saskatchewan and , south to central Mexico, and from Manitoba’s Species At Risk Cool Manitoba’s Endangered Species Act, and is Facts also protected under Manitoba’s Wildlife Act. It has been assigned a status of Special Great Plains toads call for up to three Concern by the Committee on the Status of hours after sunset and can be heard up Endangered Wildlife in Canada (COSEWIC). to two kilometres away. They often Stewardship and recovery congregate in large numbers where To date, activities in Manitoba have been their calls can be deafening. focused on gathering information such as ● population size and distribution in south- western Manitoba. Water management and Females produce up to 45,000 eggs, wetland conservation programs could prove with an average-sized female beneficial to Great Plains toads by providing habitat for regular breeding in Manitoba. producing about 10,000 eggs laid in Conservation agreements with landowners long, double-stranded strings. that maintain natural wildlife habitat could ● ensure that shallow depressions are allowed to fill with water during wet years. Great Plains toads are considered Get involved in recovery beneficial to agriculture, because they Iowa and Missouri, west to California Please contact Manitoba Conservation at eat a variety of insects that feed on, and Nevada. This toad was first found in one of the numbers below if you would like southwestern Manitoba in 1983, near and damage, crops. In Oklahoma, the more information on what you can do to Lyleton. Additional observations in the area value of this insect control to producers further enhance your land for this and other from 1986 to 1991 verified that the species native Manitoba plant and species. was estimated at $25 per toad per year. occurred regularly in Manitoba. You can help by maintaining wetlands and ● They were found in high numbers in flooded the low-lying depressions which form agricultural fields near Melita in mid- temporary wetlands during wet years. You Great Plains toad tadpoles are often May 1999. should also avoid using insecticides near eaten by the larger tadpoles of the Status wetlands, as this eliminates some insects Plains spadefoot (Scaphiopus used for food. The moist skin of and The Great Plains toad has been assigned bombifons), a slightly more common toads makes them susceptible to being a rank of rare to uncommon (S2S3) by the poisoned by pesticides. grassland toad with a similar Manitoba Conservation Data Centre. The distribution and habitat. species is also rare in Alberta and a number Manitoba Conservation of American states, but it is common in ● Wildlife and Ecosystem Protection Branch many areas, and thus is considered secure Box 24, 200 Saulteaux Crescent Observations in the Melita area in rangewide (G5) by NatureServe. Threats to the species include loss of habitat due to Winnipeg MB R3J 3W3 mid-May 1999 differed from previous drainage of temporary pools preferred for (204) 945-7775 reports of Great Plains toads in breeding. However, its use of flooded www.gov.mb.ca/natres/wildlife/index.htm Manitoba in that they were widespread agricultural fields suggests that it can handle Manitoba Conservation Regional Office and exceptionally early (temperatures a certain amount of disturbance. Application of pesticides and herbicides may also be a Western Region had not risen to levels where the concern, given the sensitivity of Brandon species is normally recorded). The to chemicals and pollutants. Roadkill by (204) 726-6450 breeding pools were leftovers from vehicles has been identified as a leading • cause of mortality. Partners in production of this fact sheet: spring runoff, mostly in cultivated Manitoba Conservation, areas. These observations suggest that The Great Plains toad was listed as Wildlife and Ecosystem Protection Branch Environment Canada, Canadian Wildlife Service the species may be more common in Threatened in 2001 by regulation under Manitoba Habitat Heritage Corporation Manitoba than previously thought.

Extirpated Species Endangered Species Threatened Species Vulnerable Species Any species once native to Any native Manitoba species Any native Manitoba species likely Species not regulated under Manitoba that has disappeared threatened to disappear through to become endangered or at risk the Endangered Species Act through all of its Manitoba range. all or most of its Manitoba range. due to low or declining numbers in but which could eventually Extirpated species are declared as Endangered species are declared Manitoba if the factors affecting it be considered Endangered such by regulation under the as such by regulation under the don’t improve. Threatened species or Threatened if the factors Endangered Species Act. Endangered Species Act. are declared as such by regulation affecting them do not under the Endangered Species Act. improve.