The Western Toad is in the family Bufonidae, the true toads. Toads are easily recognized by their relatively short limbs and rough, warty skin that typically appear as spots on the body. Behind the eyes are prominent parotoid glands, which can exude a toxin as a defensive measure. Toads are more terrestrial than frogs, and can be found relatively far from permanent bodies of water. Twenty-five species of the genus Bufo occur in North America (Natureserve Explorer, 2005), but B. boreas is the only Bufonid toad found in British Columbia.
The BC Frogwatch Program (BC Ministry of Environment 2009) descibes Western Toads as follows: 'Adult Western Toads have stocky bodies with short legs, and tend to walk rather than hop. Their thick skin appears dry and bumpy and can range in colour from pale green to grey, dark brown, and red. They typically have pale-coloured bellies mottled with black, and a pale coloured stripe down their backs. Their beautiful gold-flecked eyes have distinctive horizontal oval pupils. Behind each eye is a prominent oblong or kidney-shaped swelling called a parotoid gland. Adults range from 5.5 to 14.5 centimetres in body length, excluding the hind legs. Males are generally smaller than females and have dark pads on their thumbs that help them cling to the female during mating. Their skin is usually less rough and blotched than the females' skin.'
Western Toads are mostly nocturnal, but can be found during the day at higher elevations and latitudes (BC Ministry of Environment, 2009).