Morone americana
White perch are deep bodied fish with small pointed teeth. They are usually about 7 to 10 inches long, and weigh from 8 ounces to 1 pound. They have a white belly and dark green-grey on their back. During the breeding season, the chin may turn purplish, and the fins may turn red at the base.
White perch are normally found along the Atlantic coast of North America from New Jersey to South Carolina. They have been introduced into Lake Erie and Lake Ontario, and many smaller lakes.
White perch usually live in estuaries (such as the Chesapeake Bay), where the water is slightly salty. They can also live in fresh water, as in Lake Erie and Lake Ontario.
White perch eggs take 2 to 5 days to hatch. When they first hatch, the tiny young are called prolarvae. They are only 2 or 3 mm long, and do not have fins yet. They have no mouths yet, so they use stored food energy from their yolk sac. They also cannot see yet.
After about 13 days, the prolarvae have grown to about 4 mm long. Their mouths develop, and their eyes begin to work. They are now called postlarvae.
When the postlarvae are 7 to 9 mm long, their fins develop and they are called juveniles. The juveniles stay in creeks and rivers where the water is murky and there are many plants.
White perch become adults when they are 2 to 4 years old, and males are 72 to 80 mm long and females are 90 to 98 mm long. When there are many fish in an area, they may not grow as large.
When a female white perch is ready to mate, a group of males surrounds her. She releases her eggs into the water and they stick to the bottom. All the males release their sperm at the same time, so the eggs can be fertilized by different fathers.
White perch breed once a year between March and July. They can breed in many kinds of habitat, but they always choose water that is less than 7 m deep. Some white perch breed in the same place they live, but many travel long distances to find good breeding habitat, especially if they live in the ocean. They can reproduce in water that is somewhat salty, but they prefer fresh water.
White perch usually lay their eggs in the evening or after it rains. Each female can lay between 20,000 and 200,000 eggs. The eggs stick together in a clump and may also stick to the bottom. The parents then leave and do not take care of the eggs.
Adult white perch do not take care of their eggs or larvae.
Little is known about the lifespan of white perch. However, closely related species such as river perch, european perch, and largemouth bass live up to 15 to 25 years.
Juvelines group together in shallow weedy areas. They may leave these areas during the day to find food, but they return at night.
In the winter, both juveniles and adults move to deep pools where the water is slightly salty. In spring, the adults move upstream to shallow fresh water to breed. Then they return to deep water for the summer.
White perch do not guard their territory from each other, and they usually stay within a 19 km area.
Little is known about how white perch communicate. They are able to see, hear and smell, and they can detect vibrations in the water.
Adult white perch mainly eat other fish, but the young eat eggs, insects, worms, crustaceans and small pieces of animal debris.
White perch are more likely to be eaten when they are young than when they are adults. Adults are eaten by striped bass, walleye, bluefish and weakfish, and eggs and larvae are eaten by bluegill, copepods and other white perch.
White perch produce a large number of young instead of relying on camouflage or predator avoidance behavior. This way, even if many young are eaten, some will still survive to reproduce.
White perch are important to their ecosystem both as predators and as prey.
Because they are an invasive species in some areas, white perch may have negative effects on native fish that are economically important.
White perch are important to humans as a source of food and recreational fishing. Many millions are caught each year, especially along the Atlantic coast from Massachusetts to North Carolina.
Because they are able to use many different habitats and food sources, and because they have large numbers of offspring, white perch are very common and do not have any special protection status.
Recorded infections in Connecticut of Epitheliocystis Bacterial Diseases are the only listed diseases affecting white perch. (Heemstra, 2002)
Aaron Martens (author), Eastern Kentucky University, Sherry Harrel (editor, instructor), Eastern Kentucky University.
Mary Hejna (editor), University of Michigan-Ann Arbor.
University of Michigan. 1995. "Animal Diversity Web Site" (On-line). Class Actinopterygii. Accessed October 26, 2005 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Actinopterygii.html.
University of Wisconsin Seagrant Institute. 2002. "White perch" (On-line). Fish of the Great Lakes. Accessed September 23, 2006 at http://www.seagrant.wisc.edu/greatlakesfish/whiteperch.html.
Etnier, D., W. Starnes. 1993. The Fishes of Tennesse. Knoxville: The University of Tennesse Press.
Heemstra, P. 2002. "Fish Base" (On-line). Morone americana. Accessed October 24, 2005 at http://www.fishbase.org/Summary/speciesSummary.php?ID=355&genusname=Morone&speciesname=americana.
Jackson, L., C. Sullivan. 1995. Reproduction of White Perch: The Annual Gametogenic Cycle. Transactions of the American Fisheries Society, 124: 563-557.
Stanley, J., D. Danie. 1983. "White Perch" (On-line). Accessed October 23, 2005 at http://www.nwrc.usgs.gov/wdb/pub/0199.pdf.