Ictalurids in South Dakota

Nine species of ictalurids have been recorded in South Dakota, but only eight have been found recently (channel catfish Ictalurus punctatus, blue catfish I. furcatus, black bullhead Ameiurus melas, brown bullhead A. nebulosus, yellow bullhead A. natalis, tadpole madtom Noturus gyrinus, stonecat N. flavus, flathead catfish Pylodictis olivaris). The slender madtom N. exilis has not been recently captured. Our objectives were to summarize new data on ictalurid distribution and population metrics for selected species, characterize the recreational fishery, and discuss factors affecting ictalurid populations. The stonecat, black bullhead, and channel catfish are common and distributed statewide. Tadpole madtoms, and brown and yellow bullhead are found only in eastern rivers, but yellow bullhead were recently collected in the Cheyenne River in the west. The rare blue catfish and the common flathead catfish are found in the Missouri River and in the downstream portions of major tributaries. Relative abundance and catch-per-unit-effort data are presented for common species. In two Missouri River reservoirs, catch-per-unit-effort for channel catfish has been stable over 17 years (about 2-5 fish/gill-net), whereas in two other Missouri River reservoirs the catch has been 10-15 fish/gill-net since 1988. There was great (mean = 56%) annual variability among years in proportional stock density, but no temporal trends were evident. Relative weight patterns for channel catfish were similar from rivers in the Northern Glaciated and Western Xeric ecoregions. Missouri River anglers ranked catfish as fourth most preferred species, but catfish were ranked higher by anglers on the James and Big Sioux rivers where five ictalurid species were caught. Factors influencing the ictalurid populations in South Dakota are fish management, habitat quality, barriers, and fish immigration from the Missouri River. The populations of all species, except slender madtom, seem to be stable or expanding.