formerly Rana septentrionalis
Mink Frog / Grenouille du Nord
The Mink Frog is a moderate sized frog, olive to brown in colour and may have dark
spots or mottling on the sides and hind legs. The belly is yellowish and the
dorsolateral ridges may be
prominent, partial or absent. It has a large
tympanum and slightly
upturned eyes. The name Mink Frog refers to its pungent, musky odour. The webbing on
the hind foot reaches the last joint of the longest toe. Adults may reach 7 cm.
The Mink Frog
call consists of a rapid series of three or more croaks like the tapping
of a metal hammer on wood. It is easily confused with that of the Northern Green
Frog but lacks the twangy bounce of that call. A large chorus sounds like popcorn
The Northern Green Frog is similar although
it can get larger and always has partial dorsolateral ridges. In addition, the Northern
Green Frog has a white belly.
The Mink Frog is a northern species which has most of its distribution in Canada. It
is found in southern Manitoba, and through much of Ontario, Quebec, New Brunswick,
Nova Scotia and Labrador. It is also found in some states in the Great Lakes basin.
The Mink Frog is highly aquatic and rarely found on land. It prefers large, cold,
permanent ponds, lakes and slow moving rivers with abundant vegetation.
Breeding occurs from late spring through mid summer. Choruses increase in intensity
through the night and peak before dawn. Egg masses are globular but have never been
observed in the wild. Tadpoles overwinter in water before transforming.
Mink Frogs are very aquatic but may be seen on land in late fall. They are more
skittish than Northern Green Frogs and Bullfrogs. Adults hibernate under water.
The Mink Frog is one of the few species of amphibians with most of its distribution
in Canada. Populations are apparently stable.