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Description
A green or brown frog with large, light-edged spots. Leopard Frogs also have prominent
light-coloured dorsolateral
ridges and a white belly. They can grow to over 10 cm body length but this is
quite rare. Adults are usually 5-8 cm.
Call
The male's call
is a low snore followed by several low grunts and does not carry very
far. Sometimes it sounds like a finger rubbed on a wet balloon. It is
similar to the call of the Pickerel Frog but more complex.
Confusing Species
In eastern Canada the Leopard Frog is most similar to the
Pickerel Frog. The Pickerel Frog has more
squarish spots, a yellow belly and is always brown. In western Canada there are no
other large frogs with large spots.
Distribution
The Leopard Frog is found in every province and territory with the exception of the
Yukon. It is found in only southeastern British Columbia and the southern portions of
the Northwest Territories. Leopard Frogs occur across most of central and eastern
Canada. They are native to Labrador, and are introduced on the island of Newfoundland.
They are also found through much of the northern United States.
Habitat
Leopard Frogs occupy a wide range of habitats from prairie to woodland to tundra.
They are often found a considerable distance from open water.
Reproduction
Breeding occurs in mid-late spring in relatively permanent ponds without fish. Egg
masses are attached to submerged vegetation. A female can lay up to 7000 eggs although
half this number is more typical. The eggs are approximately 1.5 mm in diameter and
hatch in one to three weeks depending upon the temperature. Tadpoles transform in mid
to late summer.
Natural History
The Northern Leopard Frog is part of a large complex of closely related species that
range across all of North America. Only the Northern Leopard Frog is found in Canada.
Leopard Frogs eat a wide variety of prey, but mainly insects, spiders and other small
invertebrates. They are eaten by snakes, turtles, herons and raccoons, to name but a
few predators. Winters are spent on the bottom of waterbodies that do not freeze
solid. In many areas Leopard Frogs hibernate in different ponds from where they breed.
It takes a Leopard Frog approximately two years to reach maturity. In captivity, they
have lived for up to nine years although individuals in the wild would likely only
live to age three or four.
Conservation Concerns
In western Canada Leopard Frogs have dramatically declined over the last few decades.
They virtually disappeared from Manitoba in the late 1970s and large declines have
also been reported from Alberta.There is some evidence that they have also declined
in northern Ontario.Populations appear to have stabilized and in some instances
increased.Although the cause of the decline has not been confirmed, possible causes
are long-term drought and habitat loss. The Northern Leopard Frog is designated
Endangered in British Columbia, Special Concern in the north and the prairies
(Northwest Territories, Alberta, Saskatchewan, Manitoba) and not at risk in eastern
Canada by COSEWIC.
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