Catfish in Miniature

By Mark Goodwin | July 2, 2004
From Missouri Conservationist: Jul 2004
THIS CONTENT IS ARCHIVED
Body

To most people, the word "catfish" means channel, blue and flathead catfish. Those are the species most commonly pursued by Missouri anglers. Madtoms, Missouri's most varied group of catfish, are seldom mentioned.

Nine of the 15 species of catfish native to Missouri are madtoms. Though common in many streams across the state, madtoms are overlooked because of their small size. Seldom reaching 5 inches in length or weighing more than 2 ounces, madtoms hold no sporting value. In form and behavior, however, they are catfish in every way, and they represent part of the rich variety of wildlife of Missouri's streams.

Madtom Identification

All madtoms are small, but so are young channel cats and flatheads. How can you distinguish madtoms from catfish fingerlings?

Like all catfish in Missouri, madtoms belong to the family Ictaluridae. Like their bigger cousins, madtoms have eight whiskers or barbels--four on their upper jaw and four on their lower jaw. Like all Missouri catfish, madtoms have scaleless skin. A madtom's adipose fin--a fleshy, rayless lobe behind the dorsal fin--is different from the adipose fin of other catfish, however.

Madtom adipose fins form a low, keel-like ridge that either connects to the tail fin or has only a slight notch between it and the tail fin. On larger catfish, the adipose fin is free and more widely separated from the tail fin. The genus to which madtoms belong, Noturus, means "back tail," referring to this distinctive connection of the adipose and tail fin.

Madtom Ecology

Madtoms are part of the complex web of feeding relationships that occur in streams. Though small, madtoms are often abundant in streams, and their populations represent a significant link in the food chain.

Like bigger catfish, madtoms are mostly nocturnal. During the day they hide under rocks and leafy debris. At night madtoms emerge and forage voraciously. They eat a variety of small, aquatic insects, including the nymphs of mayflies, dragonflies and damselflies. They also eat small crustaceans, including aquatic pill bugs and immature crawdads.

In turn, madtoms are eaten by larger fish, including smallmouth bass, walleye and trout. Some anglers collect them for bait.

Most of Missouri's madtoms live in the riffles of streams, where they reside under rocks and stones. A good way to catch them is by "kick seining." Holding a short seine downstream with the lead line held tight to the bottom, slowly walk backward upstream while kicking the gravel or rocks on the bottom. The current will sweep dislodged madtoms into your net. Because madtoms are small, the seine should have no larger than 1/4 inch mesh.

Three people can seine more efficiently by having two holding the seine while the "kicker" walks slowly downstream toward them.

You can also catch madtoms at night in riffles using a small-mesh dip net and a flashlight. Most youngsters love to try catching madtoms on overnight camping trips along Missouri's clear streams.

Madtom Species

The Fishes of Missouri, by William L. Pflieger, contains information and classification facts concerning all the fish species found in our state. You can purchase or order this book through your regional conservation office or at a conservation nature center or online.

You are unlikely to come across the mountain madtom, Noturus eleutherus, or the Neosho madtom, Noturus placidus. Both have very limited distribution in Missouri. The mountain madtom has only been collected at four locations in Missouri, including 18 specimens collected from the Black River and St. Francis rivers.

The tadpole madtom, Noturus gyrinus, is the most abundant madtom in the lowland streams and ditches of southeast Missouri. It is also found in the creeks and backwaters of the Missouri and Mississippi rivers. The tadpole madtom is most often collected from quiet waters that have thick growths of submergent plants or accumulations of leaves, sticks and other organic debris.

The distribution of the freckled madtom, Noturus nocturnus, is similar to that of the tadpole madtom, but they are typically found in riffles or in portions of the stream that have gravel or rocky bottoms.

Noturus miurus, the brindled madtom, also inhabits many of the same lowland streams and ditches as the tadpole madtom, and is nearly as common. Brindled madtoms are more often found in pools, however. The species also inhabits the Spring River system in southwest Missouri.

In the western and northern Missouri Ozarks, the slender madtom, Noturus exilis, is the most common madtom in smalland medium-size streams that have gravel bottoms, clear water and permanent flow. This madtom is scarce in the southern Ozarks.

The stonecat, Noturus flavus, is the most common madtom in the large streams in the northern Ozarks and Prairie region. In the headwaters of these streams, it is often replaced by the slender madtom.

In the southern Ozarks of Missouri, the Ozark madtom, Noturus albater, is the most abundant madtom. It thrives in clear, steep streams with strong, permanent flow.

The checkered madtom, Noturus flavater, has a similar distribution to that of the Ozark madtom, except that it is absent from the St. Francis and Black rivers. In streams where it co-exists with Ozark madtoms, it is generally less abundant. Unlike the checkered madtom, it prefers backwaters and margins of quiet pools that offer thick accumulations of leaves, sticks and other organic debris.

The next time you seine bait for a stream-fishing trip, take a look at the occasional small catfish you net. Chances are it's not a fingerling catfish, but a madtom.

HANDLE WITH CARE!

These diminutive catfish can inflict a painful puncture wound with the spines on their pectoral and dorsal fins. Like all of Missouri's catfish species, madtoms have venom glands at the base of these fins. The glands secrete venom that becomes incorporated in the slime and cells that make up the spine.

Because madtoms are so small, it's difficult to avoid their tiny, sharp spines, especially if you are trying to impale them on a fishing hook. Many describe the pain that comes from being "horned" by a madtom as similar to a bee sting. Others claim it to be much worse. It's best to handle madtoms carefully.

MADTOMS IN HOME AQUARIUMS

Madtoms make ideal aquarium inhabitants. Even as adults, they are too small to eat most aquarium fish.

During the day, madtoms typically hide under rocks or other aquarium structures,with maybe only their whiskered chins sticking out. Place food in the aquarium, however, and they quickly swim out to feed.

Madtoms are particularly well suited for aquariums set up for native fish. Minnows,madtoms, darters and topminnows all adapt well to aquarium life and are resistant to the diseases that often plague tropical fish. With a valid Missouri fishing permit, you can possess up to 150 bait fish. However, you cannot collect or possess endangered or threatened species, such as mountain or Neosho madtoms.

The Neosho madtom has been collected only a few times from the Spring River just upstream from Kansas-Missouri border. You should avoid kick seining where mountain and Neosho madtoms are known to occur, and it's always important that you correctly identify the species of madtoms so you can release mountain or Neosho madtoms.

However, you have a good chance of collecting Missouri's other seven species of madtoms.

This Issue's Staff

Editor - Tom Cwynar
Managing Editor - Bryan Hendricks
Art Director - Ara Clark
Artist - Dave Besenger
Artist - Mark Raithel
Photographer - Jim Rathert
Photographer - Cliff White
Staff Writer - Jim Low
Staff Writer - Joan McKee
Circulation - Laura Scheuler