Development of a Qualitative System to Evaluate Populations of Channel Catfish211 and Flathead Catfish in the Missouri and Mississippi Rivers. Sport Fish 211 Restoration Project

摘要

Managers of big river catfish populations want to know current population status211u001eand how it compares to previous samples or other populations in similar 211u001eenvironments, and they need a standardized methodology to make the assessment. 211u001eThis study was initiated to determine how to collect large numbers of channel 211u001ecatfish and flathead catfish in a short period of time, and to provide baseline 211u001einformation useful to assess channel catfish and flathead catfish populations in 211u001ethe Missouri and Mississippi rivers. Channel catfish and flathead catfish were 211u001esampled in the Missouri and Mississippi rivers from 1980 to 1992 with 211u001estandardized techniques, and populations were assessed with capture rates, growth 211u001erates, and size and age structure, mortality rates, and population modeling. 211u001eChannel catfish were sampled at one site on the Missouri River with baited hoop 211u001enets. Flathead catfish were sampled at four sites on the Missouri River and two 211u001esites on the Mississippi River by pulsed DC electrofishing. Channel catfish 10.0 211u001einches and longer, and flathead catfish 6.0 inches and longer were considered 211u001efully recruited to the sampling gear.