Although Ohio has some 180 freshwater fish species living in the State’s lakes and streams, it is home to only one endemic species: the Scioto Madtom, Noturus trautmani.
In November of 1943, when OSU Museum of Zoology Curator Milton Trautman captured the little catfish from his favorite locality, he recognized that it was not a form that he’d encountered during his multitudinous collecting trips.
OSUM 5914 – Noturus trautmani
These fish, which were later described and named in his honor, are similar to the Elegant Madtom, Noturus elegans. A study carried out by W. Ralph Taylor (1969) recognized those similarities in describing the Scioto Madtom and placing it close to the Elegant Madtom phylogenetically (substantiated in a 2009 publication by Egge and Simons), although osteologically the two are quite different. Icthyologists postulate that the Scioto Madtom may have speciated from an elegans population following a glaciation event.
OSUM 9575 – Noturus trautmani – Cleared and Stained preparation.
Note arrows showing anterior pectoral fin spines and humeral process significantly shorter than those characters on the Noturus elegans specimen below (vertebral counts also separate the two species)
OSUM 18913 – Noturus elegans – Cleared and Stained preparation.
Although anatomical features and a unique color pattern were used to justify recognizing the Scioto madtom as a distinct species, several local fish enthusiasts have wondered whether the Scioto Madtom population were simply hybrids between the Stonecat Madtom Noturus flavus, which resembles the Scioto Madtom in coloration and in possessing a low adipose fin, and Noturus stigmosus, which has long pectoral barbs and humeral processes but strong saddle markings on its body. However, no instance of hybridization between these species has been reported, although other hybridizations are reported among madtoms.
The length of Big Darby Creek from which Milton captured almost all of what was later called the Scioto Madtom are recorded in our catalog book as 100-200’ above the State Route 104 bridge. The first Scioto Madtom specimens collected were found in Riffle No. 3 of a series of four riffles and runs called “Trautman’s Riffle”.
Drawing of Trautman’s Riffle from Gilfillan, Merrill C. 1963. The Fishes of Trautman’s Riffle. Ohio Conservation Bulletin, Vol. 27, No. 5. pp. 22-24.
Trautman’s Riffle on Big Darby Creek upstream of State Route 104. Photo by Anthony Sasson of The Nature Conservancy.
Trautman and his successor in the OSUM Fish division, Ted Cavender, both searched extensively for populations of Scioto Madtoms outside of the type locality. These collections led to the discovery of other species of madtoms, but failed to unearth another population of Scioto Madtoms (the last one collected was in Autumn of 1957).
My introduction to Trautman’s Riffle didn’t happen until the mid-1990’s. Although I’d spent many a day on lakes, reservoirs and rivers fishing with my grandfathers, my fishing experiences had not included seining until I took Ichthyology at OSU with Ted Cavender.
Ted Cavender (center), OSUM Curator 1970-2005, with his OSU Biology of Fishes class at the Scioto River fishing access just east of the Big Darby Creek confluence, ca. 2002.
In the 20 years since this introduction, I have personally observed some of the riffles in the vicinity of Trautman’s Riffle moving, due to the “flashy” flooding character of the stream. One such riffle downstream from Trautman’s Riffle headed up under the State Route 104 bridge to about 50 yards downstream, and some of the structure appears to have moved down to an area at the next major bend in the stream’s course. Despite the dynamism of the Big Darby in this stretch, Trautman’s Riffle remains mostly intact, although it seems to have been better defined when Milton collected the Scioto Madtom back in the 1940’s and 1950’s.
The increased propensity for flooding and the increased impact of these floods in Big Darby Creek is due at least in part to anthropogenic changes to the topography of the watershed as well as to its hydrology. Clearing of the riparian area right up to the edge of the creek removes the trees, brush and grasses that serve as a natural filter for pollutants like smothering silt loads from farm field tillage and removes tree roots that hold the upper layer of dirt and enable the stream to create undercut areas where fish hide. A natural riparian buffer also furnishes woody debris that falls into the stream, creating more habitat and egg laying areas for fish.
Could a flooding event, other weather conditions, or impacts such as siltation of substrates from agricultural tillage, have affected the Scioto Madtom population severely enough that they were unable to propagate? A catastrophic release of silage on Little Darby Creek in the 1980’s wiped out an otherwise healthy population of Least brook lampreys at Mechanicsburg Ohio, demonstrating the potential impact of a rare event.
Since the Scioto Madtom was only ever found in a very small population, and subsequently not found for many years, the species was listed for decades as an endangered species. Several governmental and private monitoring agencies have sampled the site and conducted exhaustive sampling of other localities in the Scioto River and other major Ohio River tributaries, especially those that focused exclusively on habitats where Madtoms could be expected. One such effort was funded by the U.S. Fish and Wildlife Service. The 3-year project to sample the major Ohio River tributaries within the state for Madtoms turned up nets full of Northern Madtoms, Mountain Madtoms and Stonecat Madtoms, but unfortunately no Scioto Madtoms. Because of the lack of results despite intensive expert searches, many suspected it was extinct. The U.S. Fish and Wildlife Service and the Ohio Division of Wildlife concur, and have recently declared the Scioto Madtom extinct. This new listing notwithstanding, we can’t help but keep an eye out every time we are in suitable habitat for the elusive, endemic, endangered Scioto Madtom.
About the Author: Marc Kibbey is Assistant Curator of the OSU Fish Division at the Museum of Biological Diversity.