Effect of population density and feeding rate on the fathead minnow (Pimephales promelas)

Juvenile fathead minnows (Pimephales promelas) were stocked in tanks at different densities and different ration levels, in two experiments, to determine effects on final population density, growth and fecundity. Length and weight of fish increased with increased food availability. Egg size was exponentially related to growth and perhaps directly to ration level. High population density appeared to limit growth and gamete development regardless of food abundance. Additionally, water volume appeared to limit numbers (tolerance density) of fish which can be supported in a specific volume of water.