Description
The American Toad is a large, squat toad with warty brown, reddish
or olive skin and variously coloured spots and skin glands. There is often
a light line down the middle of the back. It is distinguished from other
toads by its long parotid glands which do not
touch its prominent cranial crests. Maximum
adult size is 11 cm.
Call
The call is a monotone trill up to 30 seconds long, preceded
by a single, slightly lower introductory note. In a breeding chorus each
male selects a different note to call on.
Confusing Species
The American Toad is the only toad in most of eastern Canada.
It overlaps with the Canadian Toad in central
Manitoba. The cranial crests of the Canadian Toad are fused into a bony
hump between the eyes. In extreme southern Ontario it also overlaps with
the Fowler's Toad, whose parotid glands touch the
cranial crests. American Toads can hybridize with these two species which
makes identification more difficult in the zones of overlap.
Distribution
The American Toad is widespread throughout the eastern half
of Canada from the central Manitoba and southern James Bay to Labrador
and Prince Edward Island. It is also widespread through the eastern United
States.
Habitat
American Toads are found in a wide variety of terrestrial habitats
from mown grass and gardens to heavily forested areas. They inhabit ponds
only during the breeding season and as larvae. Breeding occurs in warm,
shallow ponds, shallow streams and river margins and even large puddles
and roadside ditches.
Reproduction
American Toads breed from late March to early June depending
on how far north they are. Eggs are laid in two strands which are wrapped
around aquatic vegetation. The eggs hatch in a few days to a few weeks
and the tadpole stage lasts 50-65 days. Emerging toadlets are among the
smallest newly transformed amphibians and soon disperse into the surrounding
habitat.
Natural history
American Toads hibernate on land and burrow beneath the frost
line in the soil. Both tadpoles and toads have poison glands in the skin
which reduce their susceptibility to predators. A dog which picks up a
toad will drop it and foam at the mouth but will not be hurt. They eat
insects and small soil creatures such as worms and slugs.
Conservation Concerns
American Toads are easily attracted to backyard ponds and gardens.
There is no evidence that they have declined.
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