Lithobates palustrisPickerel Frog

Geographic Range

The Pickerel frog ranges from the Canadian Maritime Provinces south to the Carolinas and then west to southeast Minnesota and eastern Texas. However, there are many gaps in the distribution of these frogs, especially in the southern parts of Ohio, Illinois, and Indiana (Conant and Collins 1998).


Pickerel frogs commonly inhabit cool, wooded streams, seeps and springs although they are also found in many other habitats. In the South, it can also be found in the relatively warm, turbid waters of the Coastal Plain and floodplain swamps. These frogs tend to wander far into grassy fields or into weed-covered areas in the summer (Conant and Collins 1998).

  • Aquatic Biomes
  • rivers and streams

Physical Description

The Pickerel frog is a relatively large frog that is often confused with the Northern Leopard Frog (Rana pipiens). However, the Pickerel frog has chocolate-brown spots arranged in two rows between the dorsolateral folds while the Leopard frog's spots are more irregular and scattered. They can be distinguished by the bright yellow or yellow-orange color on the inside concealed surface of the thigh. Leopard frogs are white in the same area. These frogs range in size from 45 to 75 millimeters as adults. Females are usually larger than males. Male Pickerel frogs have paired vocal sacs, stout forearms and swollen thumbs. These frogs produce toxic skin secretions that are irritating to humans but can be fatal to other small animals, especially other amphibians. Many frog-eating snakes avoid these frogs for this reason (Matson 1999).



Pickerel frogs breed in late March to early May. Males have low, snore-like calls to attract females. After fertilization, females lay spherical egg masses attached to tree branches in permanent or temporary ponds. These masses may contain from 700 to 3000 eggs. Each egg has an average diameter of 1.6 millimeters when laid. After the eggs hatch, it takes around 87 to 95 days for the tadpoles to transform into small frogs and leave the water. It requires an additional two years before these frogs reach sexual maturity and are able to reproduce (Matson 1999).

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)


Pickerel frogs are nocturnal and rouse from hibernation in early spring. These frogs remain active until the end of October when they burrow into sediments in the bottom of ponds or streams and hibernate for the winter (Bokstanz 1998).

Food Habits

These frogs are carnivorous and their diet consists mostly of small insects and other invertebrates. However, as tadpoles, these frogs are herbivorous (Conant and Collins 1998).

Economic Importance for Humans: Positive

These frogs are not of great economic importance to humans. They are not caught as game and are not commonly kept as pets due to their skin secretions. They are occasionally used as fishing bait for anglers.

Economic Importance for Humans: Negative

This species does not seem to adversely affect humans at all.

Conservation Status

The population of Pickerel frogs is listed as stable, and there are no special restrictions on them. However, in many areas populations are declining due to habitat changes.

Other Comments

This species is one of very few poisonous frogs found in the United States (Matson 1999).


Karla Arnold (author), Michigan State University, James Harding (editor), Michigan State University.



living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


Bokstanz, L. 1998. Accessed October 26, 1999 at http://www.zu/

Conant, R., J. Collins. 1998. A Field Guide to Reptiles and Amphibians Eastern / Central North America. New York: Houghton Mifflin Company.

Matson, Ph. D., T. "An Introduction to the Natural History of the Frogs and Toads of Ohio" (On-line). Accessed October 26, 1999 at