Biotic And Abiotic Correlates With Black Bullhead Population Characteristics In Nebraska Sandhill Lakes
Quinton E. Phelps, Department of Wildlife and Fisheries Sciences, Box 2140B, South Dakota State University, Brookings, SD 57007; (605)688-6121; FAX (605) 688-4515; qep11@hotmail.com
Matthew J. Ward, Department of Wildlife and Fisheries Sciences, South Dakota State University, Brookings, SD 57007
Craig P. Paukert, USGS Kansas Cooperative Fish and Wildlife Research Unit, Kansas State University, Manhattan, KS
David W. Willis, Department of Wildlife and Fisheries Sciences, South Dakota
State University, Brookings, SD
57007
The black bullhead Ameiurus melas is a common species throughout the Midwestern United States. In shallow lakes, black bullhead often exhibit high population densities and biomass, although their relative impacts on sport fish populations is not well understood. We explored relationships among black bullhead population characteristics and physiochemical attributes in shallow lakes. We also quantified relationships between population characteristics of black bullhead and sport fishes. Lake characteristics and fisheries survey data were collected from the Sandhills of Nebraska from May through June, 1998 and 1999. Relative abundance of black bullheads was inversely related to proportional stock density (r=-0.672, df=15, P=0.004); however, neither relative weight nor growth were significantly (P ³ 0.20) related to bullhead relative abundance. Population characteristics of panfish species (e.g. bluegill Lepomis macrochirus, green sunfish L. cyanellus, pumpkinseed L. gibbosus, and yellow perch Perca flavescens) were not correlated with black bullhead relative abundance or size structure. Rather, PSD (r=0.655, df=10, P=0.029) and growth (r=0.59, df=11, P=0.04) of black bullhead were positively related to relative abundance of largemouth bass Micropterus salmoides. Similarly, black bullhead relative abundance was inversely related to largemouth bass size structure (r=-0.51, df=14, P= 0.05). Analysis of physiochemical parameters revealed that black bullhead mean length at age 3 was positively related to total phosphorous concentration (r=0.65, df=16, P=0.004) and bullhead relative abundance was positively related to shoreline development index (r=0.46, df=22, P=0.03). Population characteristics of black bullhead appeared to have little influence on panfish communities. Rather, black bullhead abundance, predator density, and lake productivity exhibited stronger relationships with bullhead population characteristics.