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Pickerel Frog
Rana palustris
by Jeff
LeClere
Status
No status in Minnesota.
Description
The pickerel frog is a medium sized frog
being about 3 inches in body length. Adults are tan or brown
(never green) with four to five pairs of squarish brown spots.
They have complete light gold dorsolateral ridges down the
back. The belly is plain white. There is a distinctive yellowish
wash in the groin areas and the thighs. There are brown "tiger
stripes" on the hind legs. The pickerel frog could be confused
with the very similar leopard frog. Unlike leopard frogs,
pickerel frogs are always brown (leopard frogs may be green
or brown), have square spots arranged in pairs on the back,
a yellowish wash on the thighs (leopard frogs usually have
a greenish wash), and a restricted Minnesota range.
Subspecies
There are no subspecies of the pickerel
frog, Rana palustris.
Range
The pickerel frog has been recorded in
only five counties in southeastern Minnesota.
Habitat
Pickerel frogs are found most commonly
in rivers or clear water trout streams. They may be found
in small ponds or wetlands, but usually these are near rivers
or streams. They breed in ponds and pools adjacent or connected
to streams and rivers.
Habits
Pickerel frogs breed in spring (late April,
May, and June). The male's call is a deep snore. It is shorter
and higher pitched than the leopard frogs' call and is usually
not followed by a "chuckle" as in leopard frogs. They call
from the shore or from underwater in shallow portions of the
wetland. Females lay 2,000 to 3,000 eggs. The tadpoles transform
in two or three months. Pickerel frogs usually stay close
to the water. Few move into wet habitats. I have seen pickerel
frogs away from streams in damp, forested uplands in Winona
and Houston Counties. These are usually large adults that
will not dehydrate as quickly as smaller specimens. They hibernate
in streams or rivers or may migrate to shallow ponds, if close.
Pickerel frogs produce toxic skin secretions that are distasteful
and harmful to predators. The toxin is fatal if it is absorbed
through the skin as other frogs (even other pickerel frogs)
have been killed when they are placed in a small container
with pickerel frogs.
Food
Pickerel frogs consume insects, earthworms,
and other invertebrates.
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