Spotlight on The Great Basin Spadefoot: “It Isn’t Easy Being Green”

CLICK HERE for a pdf version of our handout on this topic

Not quite a toad and not quite a frog, this unique desert adapted amphibian depends on more than one habitat type, wetland/riparian, grassland and coniferous forest, to survive and breed. Degradation of these habitats has posed a threat to the survival of this amazing amphibian.

Latin name: Spea intermontana

Federally listed as Threatened and provincially Blue-listed

Characteristics:
The Great Basin Spadefoot is a small amphibian resembling a toad that is approximately 40 to 64 mm in length. It has short limbs and a blunt snout with distinctive vertical pupils. The adults are grayish-green with brown or reddish spots. The most outstanding feature of this amphibian are the “boots or spades” on its hind feet. These assist with digging as these amphibians will burrow into soil and shrubs such as the antelope brush.  The Spadefoot is a nocturnal forager who eats a variety of insects and aquatic plants.  They spend most of their time underground to hide from summer sun and winter frost. The adult male makes a snoring-croaking sound similar to “Gwaaaaah” in order to attract female Spadefoots.

Habitat and Breeding:

The Great Basin Spadefoot uses three habitat types in the South Okanagan Similkameen.
It requires wetland habitat for breeding and riparian (shoreline), grassland shrub steppe and coniferous forest for adult-foraging. This amphibian needs wetlands such as ponds, marshes, temporary pools (ephemeral ponds) for laying eggs and the development of tadpoles.
Sub adult and adult Spadefoots require deep loose soils for burrowing from the hot sun, hibernating during the winter months and foraging for food. 

Threats:

Loss of breeding habitat due to degradation of ponds and wetlands from off road vehicles and urban and agricultural expansion is the number one threat to the population decline of the Spadefoot

Invasive and introduced species such as bass, perch and the American Bullfrog are eating eggs, larvae and adults.

Urban and agricultural development of grasslands and forest is greatly affecting the terrestrial adult Spadefoots.

Since these amphibians travel from one habitat to another, they are greatly affected by road mortality.
What you can do to help the Great Basin Spadefoot and other South Okanagan Similkameen amphibians at risk:

• Maintain and restore ponds, seasonal flooded areas and wetlands so amphibians can use them.
• Maintain riparian (shoreline) areas around ponds and wetlands
• Please do not release pet frogs or fish into natural ponds or wetland areas. Bullfrogs and non-native fish are major predators to local amphibians
• Keep cattle and horses away from ponds and wetlands or restrict their access
• Please do not ride bikes or ATVs near wet meadows or ponds. Eggs and tadpoles will get squished!
• Use pesticides responsibly and remember that run-off chemicals can get into local water systems
• Maintain grassland shrub steppe habitat especially that within the vicinity of a wetland area

For more information on this and other South Okanagan Similkameen species at risk, please contact OSCA at or visit http://www.osca.org or http://www.soscp.org. If you have a property with a wetland and you would like more information about it, please call the SOS Stewardship Program at 250-492-0173.