Extinct Ohio fish befuddles biologists

stonecat madtom
While the Scioto madtom was recently declared extinct, the Stonecat madtom is the most widely distributed species of the madtom family and is so plentiful it is listed as “common” in Ohio. While most madtoms attain a length of only two inches, the Stonecat can sometimes grow to five inches or more. (Tim Daniel, Ohio Division of Wildlife, photo)

When the U.S. Fish and Wildlife Service recently declared the Scioto madtom — a type of catfish — extinct, people probably imagined it was one of those two-foot-long whiskered beasts that Ohio anglers love to fight. And that it must have put up a heck of a fight with a name like madtom.

In reality, the Scioto madtom was probably 2 inches long, like most of the other madtoms that still inhabit waters in Ohio and other places. Their name perhaps came from the reaction of humans when they got stuck with the sharp spines at the front of their dorsal and pectoral fins. The little fish uses these as weapons, purposely sticking them straight out when threatened.

The Scioto madtom was not only native to Ohio, it was found only in Ohio in one small section of Big Darby Creek, which flows into the Scioto River. If the Scioto madtom had lived in other states and could still be found in those places, it would have just been declared “extirpated,” or disappeared, from Ohio.

But the Ohio Division of Wildlife’s definition of “extinct” is that a species or subspecies that was in Ohio at the time of European settlement and has disappeared from its entire range … well, it has basically disappeared off the face of the earth.

“Extinct means it’s gone gone,” said John Navarro, administrator for the Ohio Division of Wildlife’s Aquatic Stewardship program. “And we just hate to see that.”

Anomaly. The announcement of its extinction brought some speculation that the Scioto madtom may have been a canary in the coal mine and had succumbed to industrial and agricultural runoff and other pollution. But Navarro noted that the bluebreast darter, another species that lives in Big Darby Creek, used to be endangered but is no longer on any list “because its population has exploded.”

“The Big Darby flows into portions of the Scioto River that have reached the highest rating of Exceptional Warm Water Habitat,” he said.

And it’s probably no coincidence that the Clean Water Act is celebrating its 50th anniversary. “It’s been a game changer,” he added.

There is concern, however, about the expansion of Columbus and pressure on Big Darby Creek from development. Starting in 2004, the Franklin County commissioners began to meet with officials of Columbus and eight other cities and townships to talk about preserving the 557 square miles of the Big Darby Watershed, the largest undeveloped area in the county and home to 38 rare fish and mussel species.

The watershed “is one of the most biologically diverse aquatic systems in the Midwest and is among the top warm freshwater habitats in the nation,” it says on the home page of the Big Darby Accord, which pledges $6 million for the project.

Navarro believes the Scioto madtom’s disappearance is more the result of its self-imposed restriction to one little area of the Big Darby.

“Some are putting a negative spin on (its extinction,) but it’s really kind of an anomaly since other species in that area, including other madtoms, are doing pretty well,” he said. “I think that being in such a highly localized area, its time was coming.”

Other madtoms. The Scioto madtom was first collected in November of 1943 — November is when madtoms are most active — and last collected in 1957. “But it wasn’t for lack of trying,” Navarro said, comparing it to Indiana Jones and others searching for the Ark of the Covenant.

In addition to being tiny, the madtom is also secretive, spending the day hiding under rocks and coming out at night to eat.

Madtoms live in what’s called riffle habitat, shallow areas of the creek that you can walk across, Navarro explained. Even endangered or threatened species can do well in that habitat because it offers more diversity, more places to hide and more oxygen since the water is always stirred up.

It also offers more food, especially aquatic insects. They start as larvae in these shallow parts of streams, where madtoms and other species can feast on them before they mature and fly away.

There are no visual records of the Scioto madtom except some drawings, but Brian Zimmerman, rare and endangered/non-game fish biologist for Ohio State University, says the elegant madtom is the most similar species alive today. A bit pinkish in color, the elegant is found only in the Green River of Kentucky.

elegant madtom
There are no photos of the Scioto madtom, which was recently listed as extinct by the U. S. Fish and Wildlife Service. However the Elegant madtom, found only in the Green River in Kentucky, is the most similar to the Scioto among the madtoms still living today. (Brian Zimmerman, Rare and Endangered/Non-Game Fish Biologist, Ohio State University, photo)

Wikipedia says that madtoms are “the most species-rich family of catfish in North America, native to the central and eastern United States and adjacent parts of Canada.” It notes that some members of the family have venom in those nasty spikes.

Also, other types of madtoms that can still be found in Ohio seem to be going in the opposite direction of extinction. The northern madtom is listed as endangered, and the mountain madtom as threatened, but both have been doing better in recent years, Navarro said.

Meanwhile, the brindled, tadpole and stonecat madtoms are all listed as common, he said. The stonecat, named for its habit of hiding under stones, is the most widely distributed species of madtom, even reaching into the northern realms. Plus, the stonecat is a giant among madtoms, perhaps reaching a length of five inches.

Because they’re common, it’s even legal to catch one of these madtoms and put it in your aquarium.

“Though I don’t know why anyone would want to,” Navarro said.

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  1. Nice article. Sorry to see the Scioto madtom go. I have thought that madtoms, being catfishes, perhaps derived their name from the habit of sometimes arching their backs when handled, similar to the pose of a mad tomcat.


    Joe T.

  2. The madtoms are a neat variety of catfish’s. I’ve caught and kept the stonecat madtoms in my aquarium before, and currently I have two brindled madtoms, 3 blunt nose minnows and 5 spotfin shiners in my native tank. They’ve adapted well, however, as expected, the cats only come out at night.


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