| Species | Bufo woodhousii Girard |
| Family | Bufonidae) (True Toads) |
| Status | State Monitor |
| State Rank | S3 |
| Global Rank | G5 |
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This is a medium to large (45-125 mm snout-vent length) terrestrial toad with a stout body, broad waist, short legs, a round head and short snout. The skin is warty and the parotoid glands are elongate. Prominent L-shaped cranial crests are present between and behind the eyes. The ground color is gray, light brown or olive with dark blotches and spots. The underside is light colored with small dark blotches. The dorsal stripe is white. Males have a dark throat. The tadpole is small (less than 25 mm total length), has a depressed body with dorsal eyes, a spiracle on the left side of the body, a medial vent and a low fin that originates at the dorsal tail-body junction. The tip of the dorsal fin is rounded. The body and dorsal side of the tail musculature are darkly pigmented. Light and golden pigment appears first near the underside of the tail base and increases on the body as the tadpole grows. The tail fin and underside of the tail musculature lack pigment but may have some dark flecking. Eggs are laid in strings often mixed with eggs from other toads. Individual eggs are small, black above and white below. The advertisement call is a loud, nasal "w-a-a-a-ah" lasting about 1-1 1/2 seconds. See Photos Page.
The presence of parotoid glands distinguishes True Toads from all other anurans and the L-shaped cranial crests and elongate parotoid glands distinguish the Woodhouse's Toad from the Western Toad. These traits are not present in newly metamorphosed toads and may not be prominent in juvenile toads. Unlike Woodhouse's Toad tadpoles, Western Toad tadpoles appear uniformly black (fine gold pigmentation on the belly is visible in bright light), the dorsal fin is moderately pigmented, and the ventral fin has little or no pigmentation. The difference between the eggs of Washington's two toad species is subtle: Woodhouse's Toads have only one layer of gel, Western Toads have two. See Key Features Page.
Activity starts in late April to early May and continues into October. Adult activity is crepuscular and nocturnal; smaller toads can occasionally be found during the day. Chorusing in Franklin, Benton and Grant counties occurs from May to July depending on conditions at each breeding site. Egg development to hatching is rapid. Tadpole development is completed in approximately two months and metamorphosis occurs in the summer or fall of the first year. Over-wintering behavior has not been studied in Washington.
Woodhouse's Toads occur in the Columbia Plateau Ecoregion associated with the Columbia and Snake rivers. Occurrences on the Columbia River have been documented between the Priest Rapids Dam and John Day Dam. Occurrences have also been documented in the Eltopia and Wahluke Branch irrigation canal systems in Franklin County. See Distribution Map.
For information on the complete range of this species, see NatureServe Explorer.
Occurrences are found in shrub-steppe habitat near the Columbia and Snake rivers. Breeding takes place in a variety of still-water habitats, including shallow temporarily flooded sites, ponds and sloughs. Transformed toads are terrestrial. Habitats include riparian areas, shrub-steppe and grassland.
Distribution is limited in Washington and occurrences are in areas that have been widely converted to agriculture and urban development. Occurrence reports in the last decade have been limited to the Hanford Site (Grant and Franklin cos.), Juniper Dunes area (Franklin Co.), McNary National Wildlife Refuge (Walla Walla Co.), Alder Creek and Crow Butte State Park (Klickitat Co.).
Information is needed on the current distribution (especially along the Snake River and any sightings that occur outside the known distribution), as well as on life history attributes and habitat requirements.
This species is especially vulnerable to road traffic during movements to breeding sites in the spring and dispersal of young out of breeding sites in late summer and fall. Little else is known about threats to this species.
Corkran and Thoms (1996), McDiarmid and Altig (1999), Nussbaum et al. (1983), Stebbins (1985).
Hallock, L.A. and McAllister, K.R. 2005. Woodhouse's Toad. Washington Herp Atlas. http://www1.dnr.wa.gov/nhp/refdesk/herp/