Midwest Fish & Wildlife Conference 2016

AUTHORS: Matt Griffin*, Thad Cochran National Warmwater Aquaculture Center, Mississippi State University; Graham Rosser, Mississippi State University; Neely Alberson, Mississippi State University; Linda Pote, Mississippi State University; David Wise, Thad Cochran National Warmwater Aquaculture Center, Mississippi State University

ABSTRACT: Piscivorous birds are a major hindrance to commercial catfish aquaculture in the southeastern United States. In adddition to losses associated with depredation, the parasites transmitted by these birds cause significant economic losses in farm-raised catfish. The economic incentives for minimizing parasitic infections through targeted control have been well documented and extensive work is ongoing to identify the different hosts involved in these complex life cycles. Current research has identified at least two different snail species present in catfish ponds that transmit the digenetic trematodes Bolbophorus damnificus and Drepanocephalus auritus (=spathans), parasites of the American white pelican and the double-crested cormorant, respectively. Outbreaks of B. damnificus can have negative effects on catfish production due to parasite induced inappetence, while heavy infections of both B. damnificus and D. auritus (=spathans) can cause mortality in juvenile channel catfish. At present, control measures to reduce the deleterious effects of these parasites focus on chemical eradication of the snail hosts. In addition to B. damnificus and D. spathans, ongoing research at Mississippi State University, partnered with the Thad Cochran National Warmwater Aquaculture Center, has identified several life stages of previously undocumented digenean parasites in catfish production ponds. The impacts of these other parasite species on catfish health and production are poorly understood. Current research focuses on the development of best management practices aimed at minimizing the economic impact of parasitism on commercial catfish production.