Blue Catfish (Ictalurus furcatus)
Blue catfish are native to many river systems draining to the Gulf of Mexico, from the Mobile River to Guatemala. Their native range includes major river systems, including the Mississippi, Ohio, Missouri, Rio Grande, Tennessee and Arkansas rivers.
Blue catfish are one of the largest freshwater fish in North America. The current world record (143 lb) was caught in Buggs Island Lake (John H. Kerr Reservoir), Virginia in 2011. Numerous fish over 90 lb have been caught from this lake, and at least three over 100 lb have been caught in the last five years. Blue catfish are also long-lived fish, sometimes exceeding 30 years of age.
While blue catfish can grow quite large, growth rates can vary considerably from individual to individual and few fish actually reach trophy sizes. One study in several Oklahoma reservoirs demonstrated that less than 1% of blue catfish would ever reach 30" in length. Blue catfish had exceptional growth in Virginia's tidal rivers initially, especially in the James River. As populations have matured, growth is slowing down and the James may never again produce as many trophy-size blue catfish as it did from 2000 to 2010.
Blue catfish growth rates have been shown to be subject to "density-dependent" factors. This means fish from large populations have slower growth rates than waters with smaller populations. Consequently, commercial harvest can theoretically improve growth rates by reducing population sizes. The result could be more big fish, as long as harvest rates are monitored to prevent overfishing of trophy fish.
Blue catfish were stocked in the James, York, and Rappahannock rivers in the 1970s and 1980s to create new recreational and commercial fisheries. They have been incredibly successful in these rivers and their large abundances have generated concern for native species, including American shad, river herring, and blue crab. Blue catfish now support exceptional trophy fisheries in the Chesapeake Bay region, particularly in the James and Potomac rivers, where catfish over 50 lb are regularly caught by anglers. Many consider the James River to be the best river on earth to catch blue catfish over 50 lbs.
Blue catfish also support a growing commmercial fishery in the region, due to their excellent food quality. The market for blue catfish is growing, and blue catfish fillets are now marketed and sold as a "healthy, sustainable" wild caught fish in supermarkets such as Whole Foods and Wegman's. Although this developing market provides a means to reduce population sizes, blue catfish have been demonstrated to carry substantial concentrations of PCBs and methyl mercury (Read more). Recent work from Virginia Institute of Marine Science has shown blue catfish contaminant levels varied over space, with the upper James and upper Potomac having higher contaminant levels than the lower James and Rappahannock rivers. In addition, fat content and size of the fish were related to contaminants levels, where larger fish with high fat content generally carried greater contaminant loads.
Commercial harvest may provide a means to reduce population sizes of this non-native species, but buyers should be aware of the potential health hazards associated with consuming fish carrying high contaminant loads (Click here for current advisories). Anglers should also be sure to consult consumption advisories before consuming wild-caught fish.