Darby Creek Advocate Volume 11, Issue 1 January 2003
Creature Feature: Scioto
madtom (Noturus trautmani)
The Scioto madtom is Darby Creek’s most famous resident. It is also the creek’s
most mysterious resident.
The Scioto madtom is a tiny catfish, typically less than 2 inches long. The fish
is endemic to Darby; in other words, it has never been found anywhere else. (It
takes its name from the larger Scioto River, but it has never actually been
recorded there.) Within Darby, the Scioto has been found in only one riffle.
The fish was first discovered by Milton Trautman, Ohio’s famous 20th-century
ichthyologist, and colleague Walter Cunningham, while seining Darby in the fall of 1943. Trautman
captured two in November of that year, one the next month, then one more two years later. After
that twelve years passed before he could find the madtom again, despite frantic
efforts to locate it. Then in 1957 the fish was suddenly plentiful and 14 were
caught in the original riffle.
The Scioto madtom hasn’t been seen since. Darby’s most enduring mystery is: What
happened to the Scioto madtom?
Theories abound. Some suspect that the fish has gone the way of the passenger
pigeon, a casualty of declining water quality in Ohio streams. But diehard
experts such as Dr. Ted Cavender, Trautman’s protege, continue to hold out hope
that the fish is merely missing.
Those still looking point to the elusiveness of madtoms, which are small,
inconspicuous, and nocturnal. Madtoms make a living hiding in the dark recesses of a river,
sneaking out at night to hunt for meals.
And there is precedent for species being absent for long periods, only to
resurface years later. In fact, another madtom—the northern madtom—did just
this. For the first 31 years of seining Darby, Trautman never captured a
northern madtom. In 50 years of searching he caught only two. But today the
northern madtom is holding its own, and, though still hard to catch unless you
know exactly where to go, appears to be more plentiful than decades ago. (As a
testament to the difficulty of censusing madtoms, the EPA, which has regularly
sampled Darby since 1979, has never taken a northern madtom while
electro-fishing the stream.)
There are other opinions on the fate of the Scioto madtom. Dan Rice, formerly a
biologist for the state, speculates that the species may favor larger rivers than Darby. If true,
Trautman’s specimens may have represented a few stray individuals wandering into
Darby from the Scioto River. Dennis Mishne, with the OEPA, agrees, and wonders
if Trautman’s small population might have been stragglers escaping from the
Scioto River, which was horribly polluted by the middle of the last century. He
wonders if the Darby population may have since been outcompeted by the resident
northern madtoms.
Trautman himself speculated that the fish may live in inaccessible habitat, such
as undercut banks, where it would be unseinable under most conditions.
Some have even questioned whether the Scioto is a real species, pointing to its
superficial similarity to the northern madtom. Might the Scioto merely be a
local variant of the northern? But “normal” northern madtoms occur in the same
riffle, and it would be odd if there were two distinct populations of the same
species living in the same place. The consensus is the Scioto madtom is real.
But perhaps the biggest mystery surrounding the Scioto madtom is not that it
hasn’t been seen in years, but that it was ever seen in Darby at all.
As far as I can determine, the Scioto madtom is Ohio’s only endemic animal. In
fact, as far as fishes go, it is the only fish endemic to a single stream in any
glaciated region of North America. This is not unexpected, since endemic species
typically arise only when populations of existing species are isolated in time
and space. Glacial streams are young, and in the eastern U.S. are not isolated,
but rather intimately connected to two large drainages, the Mississippi and
Great Lakes.
As a glacial stream, and as part of the Ohio River basin, Darby is neither
ancient nor isolated. It is hard to imagine how any species there could have been isolated from a related
population long enough to diverge into a distinct species.
For this reason, the Scioto madtom doesn’t make much sense.
There is an alternative explanation—a sobering one. Perhaps the Scioto madtom
was never endemic to Darby at all. Perhaps like all other Darby fishes it was
once generally distributed throughout the Ohio River drainage, but by 1943 had
declined so dramatically that it was limited to an isolated population in a
Darby riffle. Perhaps Trautman detected the last gasp of a formerly common
species.
Even this scenario is not as probable as one might think. Despite the fact that
our country has had major water pollution problems for a long time, outright
extinction of fish species has been rare. In fact, it has only happened a few
times. Is the Scioto madtom an exception?
We may never know the answer to why the Scioto madtom appeared in Darby and, at
least so far, nowhere else. But the possibility that the fish might now be
extinct should give us pause.
After all, the species appears to have survived in Darby for a long time after
human changes began impacting water quality. More than 150 years passed between
the advent of agriculture, increased stormwater, and sewage dumping in Ohio and
in the Darby. Yet as late as 1957 the Scioto madtom was still reproducing in at
least one part of the stream. The lesson would seem to be that despite an
increased awareness of human impacts on Darby, threats to the creek have only
grown worse in recent decades. In this sense, the Scioto madtom is the perfect
symbol of both the richness and the fragility of the Darby ecosystem.
Questions of origins aside, the puzzle most people want to solve is still
whether the Scioto madtom is gone for good. Opinions vary, but it is not a good
sign that the fish has been missing so long. Still, it is quite possible that
the fish continues survive somewhere in the creek. Two years ago another fish,
the bigeye chub, miraculously reappeared in Darby after years of absence. It had
been last seen in 1964—a mere seven years after the disappearance of the Scioto
madtom.
Everyone would like for the Scioto to turn up; but even in its absence it lives
on. Because Darby remains free-flowing, and because it remains relatively clean, the cherished
hope of finding the Scioto madtom flipping and glistening in a seining net some
fine day down at the creek lives on. Add this to the list of reasons to conserve
Darby Creek.
John Tetzloff
