Troutperches and Relatives: Percopsiformes

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TROUTPERCHES AND RELATIVES: Percopsiformes

PIRATE PERCH (Aphredoderus sayanus): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Troutperches and their relatives are less than 8 inches (20 centimeters) long and have an adipose (ADD-uh-pohs) fin, a short fin between the dorsal (DOOR-suhl) fin and the tail fin. The dorsal fin is the fin along the midline of the back. If pelvic fins are present, they are located on the belly and farther back from the head than they are on other fishes. Pelvic fins, the rear pair, correspond to the rear legs of four-footed animals. The body is covered with smooth or rough scales.

GEOGRAPHIC RANGE

Troutperches and their relatives live in Alaska, Canada, and the eastern United States.

HABITAT

Troutperches and their relatives live in freshwater. Some live in swamps, and some live in caves.

DIET

Troutperches and their relatives are predators (PREH-duhters), or animals that hunt and kill other animals for food. They eat a variety of animals. Some eat members of their own species.

BEHAVIOR AND REPRODUCTION

All troutperches and their relatives live alone, but little else is known about their behavior. At least two of the species that do not live in caves are active at night. These fishes lay eggs that are penetrated by sperm and hatch outside the female's body, but little else is known about their reproduction. At least for the species that do not live in caves, spawning, or the release of eggs, takes place in the spring.

TROUTPERCHES, THEIR RELATIVES, AND PEOPLE

Some troutperches and their relatives can be found in both home and public aquariums.

Did You Know?

Troutperches are neither trouts nor perches.

Environmental Engineer

Pirate perch are considered an indicator of good water quality by the Arkansas Department of Environmental Quality for the Gulf Coastal Ecoregion.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists one species of troutperches and their relatives as Critically Endangered, or facing extremely high risk of extinction in the wild in the near future, and three as Vulnerable, or facing high risk of extinction in the wild. The U.S. Fish and Wildlife Service lists one species as Endangered, or in danger of extinction throughout all or a significant portion of its range, and one as Threatened, or likely to become endangered in the near future.

PIRATE PERCH (Aphredoderus sayanus): SPECIES ACCOUNT

Physical characteristics: Pirate perch grow to a length of 5½ inches (14 centimeters). The head and mouth are large, and the bottom jaw juts beyond the top jaw. The lateral (LAT-uhr-uhl) line, a series of pores and tiny tubes along each side of a fish's body used for sensing vibrations, is either absent or incomplete. The sides of the head are covered by rough scales. As pirate perch mature, the anus moves forward from about the middle of the belly to the throat area.


Geographic range: Pirate perch live along the Atlantic and Gulf coasts of the United States and in the Mississippi Valley.

Habitat: Pirate perch usually live over mud in quiet bodies of water, such as swamps, ponds, ditches, and pools of creeks and in small to large rivers on mud and sandy bottoms. Adults usually live on bottoms that are covered with leaf litter.


Diet: Pirate perch feed on insects, blue-green algae (AL-jee), which are plantlike growths that live in water and have no true roots, stems, or leaves, and small crustaceans (krus-TAY-shuns) and fishes. Crustaceans are water-dwelling animals that have jointed legs and a hard shell but no backbone.


Behavior and reproduction: Pirate perch live alone and are active at dusk. They release sticky eggs over leaf litter and woody debris. They live for about four years.


Pirate perch and people: Pirate perch are used for testing the quality and cleanliness of water.


Conservation status: Pirate perch are not threatened or endangered. ∎

FOR MORE INFORMATION

Books:

Berra, Tim M. Freshwater Fish Distribution. San Diego, CA: Academic Press, 2001.

Gilbert, Carter Rowell, and James D. Williams. National Audubon Society Field Guide to Fishes: North America. New York: Knopf, 2002.

Schultz, Ken. Ken Schultz's Field Guide to Freshwater Fish. New York: Wiley, 2004.

Web sites:

"Indicator Species." U.S. Environmental Protection Agency Biological Indicators of Watershed Health. http://www.epa.gov/bioindicators/html/indicator.html (accessed on October 16, 2004).

"Pirate Perch, Aphredoderus sayanus." The Virtual Aquarium. http://www.cnr.vt.edu/efish/families/aphredoderidae.html (accessed on October 4, 2004).

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Troutperches and Relatives: Percopsiformes

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