Scientific Name: Sander vitreus
Description: The walleye is a freshwater fish in the perch family that is a popular and commonly-stocked game fish. Walleye are long and thin, primarily gold and olive in color, with a white belly. The back is crossed with five or more black bands. They have two dorsal fins–one spiny and one soft-rayed. The mouth is large with sharp teeth. They have low-light vision which helps them to find prey at night.
Size: Walleye are about 30-35 inches in length and weigh up to 10-20 pounds.
Diet: Primarily small fish, like yellow perch, large invertebrates and insects, depending on what is available. Feeding occurs primarily at dusk and dawn.
Typical Lifespan: The average lifespan is approximately 10 years.
Habitat: They prefer the cool, deep, quiet waters of rivers, lakes and reservoirs. They are mostly nocturnal. During the day they are often found under cover of tree roots, logs and aquatic plants. They go to shallower waters at night.
Range: Native to Canada, the Great Lakes, the Missouri River basin and the upper Mississippi River basin. Introduced in the western and northeastern United States.
Life History and Reproduction: Walleye spawn in the spring or early summer. They spawn over gravel or rock in rivers or shallows where there is enough of a current to clear away sediment and aerate the eggs. Females can deposit more than 100,000 eggs. The eggs hatch in about two weeks.
Fun Fact: The walleye is named for its opaque, cloudy-looking eye, caused by a reflective layer of pigment called the tapetum lucidum that helps it (and other nocturnal animals) see in low light.
Conservation Status: Relatively stable. Threats include global warming, channelization, erosion, overfishing and degraded water quality from point and non-point sources. One sub-species, the blue pike, is believed to be extinct.
Global Warming and the Walleye
BioKIDS, Kids’ Inquiry of Diverse Species, University of Michigan
Blue Pike in Lake Erie, U.S. Fish & Wildlife Service
Maryland Department of Natural Resources
Michigan Department of Natural Resources
Minnesota Department of Natural Resources
NatureServe Explorer: An Online Encyclopedia of Life