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In the drainage area of the Obion river system, consistingof the North, Middle, South and Rutherford forks in northwest Tennessee, just 70 miles south of the Ohio river, the country is largely given over to farming. Most farmers keep some beef or dairy cattle and so, dig small ponds to provide water for their stock. 

These ponds are usually 3 or 4 feet deep and rarely more than 50 feet in diameter. They stay muddied all the time due to the cattle. Almost invariably, they are populated by Ameiurus natalis and Lepomis cyanellus, the yellow bullhead and green sunfish respectively. Locally they are known as the "mudcat" and "goggle eye". These two species have proven themselves ideally suited to the harsh environment that a cattle pond provides.

In the larger tributaries of the Mississippi that I have explored, the Tennessee, the Obion, and the Hatchie rivers, A. natalis is comparatively rare, the dominant catfish being the channel catfish, Ictalurus punctatus, however, A. natalis dominates in smaller tributaries and ponds. I can't say with any certainty why this is so, perhaps because A. natalis is better able to withstand the low water and oxygen depletion of the smaller bodies of water in the summer months. I have many times seen ponds stocked with I. punctatus suffer massive die-offs in August, but never a pond with A. natalis, even when the pond was so over-populated that the fish were stunted to a mature size of 4 inches long. I have even seen this catfish surviving from season to season in very shallow ponds that dry to little more than a puddle in summer.

 

 

Having mentioned the stocking of ponds with channel catfish, I. punctatus, I should explain, that in that area of America, A. natalis, locally "mudcat", is considered rather worthless. The mudcat is aptly named, as it's flesh has a distinctly muddy flavor. This can also be true of the channel catfish, but is not normally the case. The mudcat has a very large head in comparison to the channel catfish, so it dresses out much lighter than the latter of the same weight. Many ponds are deliberately stocked with channel catfish and a hybrid sunfish, Lepomis cyanellus x Lepomis macrochirus. These sunfish produce predominantly male offspring and thus can not overpopulate a pond. If it is discovered that mudcats have appeared in the pond, it is considered ruined and drained, since these fish will quickly take over. Such infestations can be from several sources; the transfer of fish from pond to pond by herons, tornados emptying farm ponds and scattering their contents, including fish, over a wide area, and small boys who release their catches into new ponds.

I was once such a small boy myself, and having caught three mudcats about 4 inches long from an overcrowded pond one spring, I released them into a new pond. This pond leaked and later in the year when the pond had dried to little more than a puddle, the three catfish had grown to about one pound each and hundreds of little catfish were present.

The largest specimen of A. natalis I ever saw weighed approximately 4 pounds. This was exceptional, the normal weight is 1 to 2 pounds. In contrast, I. punctatus regularly goes 4 four pounds, and I have seen specimens from the Tennessee river weighing in excess of 50 pounds. While 50 pounds is a rare catch, the channel catfish weighing in excess of 10 pounds are not.

In its native habitat in the Obion river water shed, A. natalis survives winters in which the ponds may be frozen over for as long as a month and summers in which their ponds may dry down to as little as one foot of depth and the water temperatures exceed 90 degrees F. 

In farm ponds, A. natalis has a variety of prey, including Amnicola limnosa, the pond snail, several species of crayfish, the tadpoles of several species of frogs and toads, and in some ponds mussels of a type similar to the Margaritifera margaritifera common to Europe. Mussel is recognized as the favorite food of catfish and it is common to see the stomach and intestine full of mussels about 1/4 inch in diameter. The catfish swallow these whole and then pass the shells. A. natalis is in turn the prey of herons, snapping turtles, and when the water is low, the raccoon, redtail hawk and even the turkey vulture. 

In the spring of the year, tight masses of A. natalis fry can sometimes be observed at the surface of the water. At this point the fry are 1/2 to 1 inch long and they hold tightly together in a circular mass, touching one another as the mass moves slowly around the pond. This is usually observed in March or April when the weather has warmed into the 70's F and after spring rains. I would imagine that breeding  A. natalis would be no problem in the British Isles for anyone with a goldfish pond. (Probably in the south of the country, Ed. see restrictions) Releasing the fish into the pond in the autumn, so that they go through the dormant cold period, should yield hundreds of fry the following spring. They would pose little or no threat to goldfish, other than smaller fancy varieties. I have seen the two coexist and flourish. One thing I would point out is that the term 'cold water aquarium' is a misnomer.

Four months of the year, most of the waters at home are hotter than tropical, and the water is still warm enough to swim in up until October. The daily high temps there just dropped below 80 F last week ( Beginning of October). The waters of the larger rivers will run in the 70's for the rest of the month, maybe well into November, depending on the rain.

It should be noted that concerns about the release of this fish into the natural habits of the British Isles are probably valid, especially for smaller waters. In the area of the Obion river watershed, this fish has proven itself capable of dominating other more desirable catfish species when conditions turn harsh.

Photo Credit: Ameiurus natalis - Konrad Schmidt.