Application of the Spawning Potential Ratio for the Middle Mississippi River Channel Catfish Fishery

Large rivers throughout the world have experienced major habitat alterations that have led to declines in fish populations.  Habitat enhancement programs have been put in place to alleviate issues associated with anthropogenic habitat alterations.  However, the implementation of harvest regulations can provide another avenue to bolster fish populations.  Harvest regulations are especially important for fish species that are commercially and recreationally harvested.  Channel catfish (Ictalurus punctatus) are important commercially and recreationally throughout the Middle Mississippi River. Understanding channel catfish population dynamics are crucial for managing the population. Current harvest regulations have not been fully evaluated, thus we evaluated the population dynamics for the Middle Mississippi River, and used simulation modeling to determine the effectiveness of various length limits on the channel catfish population.  We collected 441 channel catfish from the Middle Mississippi River during spring, summer, and fall of 2012 and 2013. Channel catfish were weighed, measured, sexed (including fecundity), and aged (via lapilli otoliths) to obtain population demographics. Overall, the channel catfish population in the Middle Mississippi could be improved by incorporating more stringent length limits into current management practices. This study has provided additional insight to ensure sustainability of the channel catfish population in the Middle Mississippi River.