In the Quad-Cities area, we are lucky to have an abundance of different fish species to pursue. In late spring, catfish are typically at the top of the catch list.
Every year I hear from local fishermen that the “blue cats” are biting well. While it is possible for a local angler to catch a blue catfish in our area rivers, it is highly unlikely it is the species that has grown to over 100 pounds in the Alton/St. Louis area of the Mississippi River.
Common names of certain fish can be numerous. Locally, I have heard at least three or four names for every common fish in the river. Channel catfish are also known as fiddlers, tommy cats, yellow cats, horn fish, and fork tails just to name a few. Blue cat is also commonly used for channel catfish in the spring as male channel catfish turn a dark blue during the breeding season. Some of the biggest channel cats of the season are caught this time of year.
Blue cats are not found naturally in the upper half of Illinois, and it is questionable on whether they were ever abundant in our area before the lock and dams were built in the 1930s and ‘40s. Blue cats, in the river, tend to be migratory in nature and usually prefer more open water than their smaller cousins. They can still be found in large numbers from the greater St. Louis area south on the Mississippi River and in several artificial impoundments within a couple hours of the Quad-Cities. I have heard a few creditable accounts as far as north as Keokuk and also near Muscatine, but never anything north of the Quad-Cities.
The best way to tell the difference between the two species is the ray count on the anal fin. Typically, blue catfish have 30 plus anal rays vs. the channel catfish with 29 or less. I say typically because there are no absolutes in fish science. The front edge of a blue catfish’s anal fin is usually squared off whereas the channel catfish anal fish is usually rounded. Those are the two quickest and most definitive ways to tell the difference between the species, but both of those characteristics can be tougher to identify when fish get bigger, older, and many times have small injuries or scars that inhibit a perfect match.
I raise thousands of blue catfish each year at the Exelon Fish Hatchery for stocking in Exelon power plant lakes across Illinois because they grow quickly in the warmer water. But in the nearly 50 years of fish sampling in the Mississippi River north of the Quad-Cities, we have never captured a single blue catfish. That does not mean there cannot be one out there, but it would be a rare catch.
If you do suspect you caught a blue catfish on the Mississippi River around the Quad-Cities, take some pictures and send me an e-mail. I would be happy to see one and finally definitively say there are blue catfish in the Mississippi River north of the Quad Cities.