Scientific Name: Novumbra hubbsi and Umbra spp.


Description: Mudminnows are not actually minnows—they are more closely related to pikes. Three mudminnow species are found in the United States—the eastern, central, and Olympic mudminnows. Eastern mudminnows are stout fish with yellow to brown bodies and horizontal stripes.

Size: Eastern mudminnows are 5 to 10 centimeters long. Central mudminnows are usually 7 to 8 centimeters, but bigger ones have been recorded near 18 centimeters.

Diet: Mudminnows mainly eat insects, snails, crustaceans, and crayfish. The largest ones eat small fish. The young eat microscopic invertebrates.

Typical Lifespan: Central mudminnows live for an average of 4 years.

Habitat: Mudminnows are freshwater fish found in streams, lakes, and wetlands. These tiny fish get their name because of their tendency to burrow into the mud to aestivate. Aestivation, which is a state of dormancy similar to hibernation, is a way for the fish to survive when most of their aquatic habitat dries up. The central mudminnow has a modified air bladder that can act as a lung and allow them to breathe oxygen from the air. This ability, combined with aestivation means that mudminnows can survive in low-oxygen conditions for days or weeks at a time.

U.S. Range: Together, the central and eastern mudminnow species range up and down the east coast and from Florida northwest to Montana and into Canada. The Olympic mudminnow is found solely in Washington.

Life History and Reproduction: The eastern mudminnow reaches reproductive age after one to two years. The eastern species spawns in March or April and then both parents guard the eggs from predators. Central mudminnows spawn around the same time, but only the female guards the eggs.

Fun Fact: Mudminnows sometimes burrow into sediment during the day to hide from predators, rather than to wait out periods of poor water quality.

Conservation Status: The Olympic mudminnow is threatened by habitat degradation and exotic species. Central and eastern mudminnows are often used as aquarium fish or bait due to their hardiness, but their populations are stable.

NatureServe Explorer  
Ohio Department of Natural Resources
Page, L. M. and Burr, B. M. The Peterson Field Guide Series: A Field Guide to Freshwater Fishes North America North of Mexico. Houghton Mifflin Company: Boston, MA 1991.
Herald, E. S. Fishes of North America. Doubleday & Compant, Inc.: New York, NY 1983.
Virginia Polytechnic Institute & State University Department of Fisheries & Wildlife Sciences 
Lake Superior Streams


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