Adult fish have stout bodies with prominently humped backs in front of the dorsal fin. They resemble channel catfish by having deeply forked tails, but are dissimilar because they are unspotted and have a long, straight-edged anal fin with 30 to 35 rays.
The back and upper sides are blue to slate gray, and the lower sides and belly are white. The internal air bladder has a constriction in the middle, giving it a two-chambered appearance.
Blues occur in big rivers and in the lower reaches of major tributaries. They prefer clearer, swifter water than other catfish, and are usually found over sand, gravel or rock bottoms. Their preferred water temperature is 77 to 82 degrees.
The spawning behavior of blue catfish appears to be similar to that of channel catfish. However, most blue catfish are not sexually mature until they reach about 24 inches in length.
Young blues eat aquatic insects and small fish while larger blues prefer crayfish, mussels and other fish. They feed primarily at night.
Blue catfish commonly attain weights of 20 to 40 pounds, and may reach weights well in excess of 100 pounds. It is reported that fish exceeding 350 pounds were landed from the Mississippi River during the late 1800's.
Blue catfish are primarily large-river fish, occurring in main channels, tributaries, and impoundments of major river systems. They tend to move upstream in the summer in search of cooler temperatures, and downstream in the winter in order to find warmer water.
18 to 24 in (460 to 610 mm).
109.25 pounds, caught in the Cooper River, Moncks Corner, South Carolina, in 1991.
The blue catfish is the largest freshwater sportfish in Texas. Where mature populations exist, 50-pounders are not unusual. Typically, the largest fish are caught by trotliners, some of whom have landed specimens in excess of 115 pounds.
The largest individuals we have encountered were in tailwaters below dams, where currents were swift and substrates consisted of sand, gravel, and rock. Blue and flathead catfish also congregate around submerged treetops. Like many other species in the family, blue catfish are opportunistic feeders, consuming live and dead fish and benthic invertebrates.
Anglers use a variety of scented baits since a catfish’s sense of smell and taste is excellent. The most effective baits include cut shad, prepared blood bait, chicken livers, shrimp, and nightcrawlers. Keep tackle simple. When fishing on the bottom use a fixed or slip sinker and when fishing the surface or suspended, try either a slip or fixed float. Hook sizes range from size 4 to 6/0 depending upon the size of fish you are seeking and the size of bait that you are using. Having a strike indicator is a good idea for catching catfish. Catfish do not “hit and run” like other fish, instead moving very slowly away with baits.
Rods and reels should be matched for the sizes of catfish that you anticipate catching. Standard tackle for flathead catfish or blue catfish, heavy rods and reels with 20 or 30 pound line may be required. Reels used for catfish should have a good drag system.
Blue catfish are native to major rivers of the Ohio, Missouri, and Mississippi river basins. The range also extends south through Texas, Mexico, and into northern Guatemala.