The Blue Catfish (Ictalurus furcatus) is a Titan among the fish fauna of North America. One historical account in 1866 from the Missouri River near Portland, Missouri weighed 315 pounds, and there are several other more recent reports of Blue’s in excess of 100 pounds. However, there have been no authenticated records for this species in either Minnesota or Wisconsin, but one unverifiable account describes a 160 pound catfish which may have been a Blue from the Minnesota River in the 1800’s. This species is reported to be migratory, and it may have once ranged this far north, but the construction of dams on the upper Mississippi River in the early 1900’s likely created impassable barriers. In 1977, the Minnesota Department of Natural Resources (MDNR) stocked 6000 Blue Cat fingerlings in the lower St. Croix River. The following year, a half pounder assumed to be from this stocking, was collected in the Mississippi River (Lake Pepin), several miles downstream of the St. Croix River. It is interesting to note that these fingerlings came from Alabama and my hypothesis is this guy was just heading south for home and warmer waters.
Coincidentally in the 1970’s, I was fanatically involved in the disdained and very seldom practiced art of catfishing (at least at that time and these latitudes). The group I went out with would hit the rivers up to three times a week and did we catch catfish. One odd thing we clearly noticed about Channel Catfish (Ictalurus punctatus) in the St. Croix was color. Most would be gray with spots, but a few were sky blue and spotless. We were all aware of the Blue Cat stocking program and assumed that’s what these were. What we were not aware of at that time was the anal fin ray count would have verified whether we had Channels (24-27 rays) or Blues (30-36 rays). Nevertheless, our group did not face a moral or ethical dilemma with these potential transplants and treated them equally as Channel’s – we found them quite edible. So much for the “body of evidence.”
I hadn’t given those sky Blue’s much thought for years and agreed with the MDNR consensus that the stocking program had probably failed. However, in 1992, a MDNR Fish Manager quite casually informed me that they had been seeing Blue Cat’s rather frequently in the St. Croix and Mississippi Rivers. I almost said in disbelief, “Excuse me!”, but mustered an encouraging request to get at least one verified and vouchered in a collection. He assured me that would be no problem, but so far no Blue’s. Also in 1992, a MDNR Nongame Wildlife Specialist asked me to check on an angler’s report of a Blue from the St. Croix River. I called him and asked if by chance he just happened to save the fish. No, because it was rare he decided to release it. A very noble deed indeed, but sure didn’t make my day. I asked (begged) that next time to save one, call me anytime, and I’d pick it up. Again, I haven’t heard a whisper.
I had believed these recent reports and very likely the sky blue catfish I used to catch were actually just a natural color phase of the Channel. Besides, none of these suspect catfish ever came close to breaking the Channel Cat state record. However, someone always has to throw a wrench into things and our President, Ray Katula, did just that. He mentioned anglers near Winona, Minnesota have claimed catching and also eating Blue’s from the Mississippi River. Ray has asked them repeatedly to save at least the anal fin to get a ray count, but he’s not having any better luck than I have had. Again these stories could be easily dismissed, but Ray has got one of his own that is difficult to ignore. He once found the carcass of a large catfish in the Mississippi River which was 4.5 to 5 feet long. I’ve been collecting with Ray and he does know fish very well, but I had to hassle him about the possibility that this may have been a Flathead Catfish (Pylodictis olivaris). No, he was certain it was not because Flathead’s don’t have forked tails.
Now, doubt makes my position far less certain. I guess the only thing left to do is pull the old fishing poles out of the attic, dust them off, and pay some visits to the old fishing holes one last time. Perhaps with some luck, I will put my nagging question to rest for good.
References
Becker, G.C. 1983. Fishes of Wisconsin. University of Wisconsin Press, Madison. 1053 pp.
Phillips, G.L., W.D. Schmid, and J.C. Underhill. 1991. Fishes of the Minnesota Region. 2nd printing. University of Minnesota Press, Minneapolis. 249 pp.
The Native Fish Conservancy