Photo courtesy of Konrad Schmidt
Troutperch - Commonname
Percopsis omiscomaycus - Scientific name
Family - Percopsidae ( troutperches)
Status : S2, G5
IDENTIFICATION: The troutperch has a large, scaleless head and a large eye. It is called a troutperch because it has an adipose fin like a trout and spines in its fins like a perch. Its body is a transparent yellow-olive to silvery color, and has rows of dark spots along the back and along the upper and middle sides. The troutperch can grow to be as long as 7.75 inches (200 mm).
SIMILAR SPECIES FOUND IN SOUTH DAKOTA: There are no species similar in South Dakota.
HABITS AND HABITAT: Troutperch are found in small to large rivers and in lakes usually over sand bottoms. Trout-perch typically eat a variety of small aquatic animals including small aquatic insects such as water fleas, and tiny clams known as fingernail clams. Large adults will occasionally go for a small minnow or darter when the opportunity presents itself. Troutperch spawn from May to August and females produce several clutches of eggs during this time. Troutperch spawn over sand and gravel areas of lakes and tributaries. Young hatch in about 5 to 8 days, dependant upon temperature.
DISTRIBUTION: Distribution Map Troutperch are widespread throughout most of Canada, below the Artic Circle and east of the Rocky Mountains, and the eastern United States as far south as West Virginia. Troutperch are also found in some lakes in Alaska. Troutperch are common in lakes throughout its range, but rare otherwise. In South Dakota troutperch have been found in the Big Sioux River above and below Sioux Falls in Brookings, Moody, Minnehaha, and Lincoln Counties. They also occur in Split Rock Creek in Minnehaha County. Farther north in the upper Big Sioux River watershed, the troutperch is found in Lake Kampeska and Pelican Lake, in Codington County.
CAUSES OF CONCERN AND CONSERVATION MEASURES: The troutperch is unique to the Big Sioux River Basin in South Dakota. Land use activities that result in erosion and sedimentation are of concern because these activities can cause the sand and gravel bottoms where this fish lives and reproduces to be covered with silt.