The American Fish Nobody Has Caught In Decades

Eighteen. That is every Scioto madtom anyone has ever collected, and all but one came out of a single spot in a single Ohio creek, a riffle so closely associated with one ichthyologist that it is literally called Trautman's Riffle. Nobody has seen one since 1957, which did not stop the federal government adding it to the endangered species list in 1975 and protecting it for the next 48 years. In October 2023 the US Fish and Wildlife Service finally conceded, removed it from the list, and declared it extinct. It was one of two American fish delisted that day, and it sits at one end of a spectrum running from definitely gone through officially disputed to quietly alive in Lake Superior the whole time.

The gap between "nobody has caught one" and "it is extinct" turns out to be surprisingly wide, legally contested, and occasionally embarrassing.

The Scioto Madtom

A small nocturnal catfish endemic to Ohio, known from exactly one population in Big Darby Creek, and possessed of the worst possible combination of traits for a species hoping to be noticed: it was tiny, it was brown, it hid under rocks all day and it only came out after dark. Seventeen of the eighteen known specimens were taken from Trautman's Riffle in 1957, which means the entire scientific record of this animal is essentially one very good afternoon.

It was among the first species on Ohio's endangered list in 1974 and received federal protection a year later, at which point it had already been missing for nearly two decades. The likely causes were siltation, industrial discharge and agricultural runoff, though the Service is careful to say nobody actually knows. It was proposed for delisting on September 30, 2021 and formally removed on October 16, 2023.

Angela Boyer, the Service's endangered species coordinator for the region, gave the least bureaucratic summary imaginable: it had been looked for and looked for and not found, and they really did believe it was gone. Sixty-six years is a long time to keep checking a riffle.

The San Marcos Gambusia

The other fish declared extinct in that same 2023 announcement, and the cause is the one that recurs across the American Southwest. The San Marcos gambusia was a small livebearer restricted to spring-fed water in central Texas, and it was lost to water overuse that reduced groundwater supply and cut spring flow. When a fish lives only in the outflow of one spring system, the fish and the spring share a fate, and pumping does not need to dry a spring completely to finish something that specialized.

Twenty-one species were delisted that day: one mammal, ten birds, eight mussels and these two fish. Mussels and freshwater fish are wildly overrepresented on every list like this, for the unglamorous reason that neither can walk anywhere else.

The Maryland Darter

This is the most entertaining entry, because two respected scientific authorities have looked at identical evidence and reached opposite conclusions, and both are still holding. The Maryland darter was discovered in 1912 in Swan Creek near Havre de Grace, was known from just two specimens until somebody rediscovered it in 1962, and from 1965 into the 1980s was thought to live in a single riffle in Deer Creek. Last confirmed sighting: 1988.

The International Union for Conservation of Nature lists it as extinct. The US Fish and Wildlife Service does not, and keeps it on the Endangered Species List, on the entirely reasonable grounds that the fish was almost impossible to find even when it definitely existed, so failing to find it now proves considerably less than it would for something conspicuous.

It is also named after the only state it has ever been recorded in, which is either admirably specific or a branding decision nobody thought through. Maryland has a state fish, a state dinosaur and a state crustacean, and this one has spent 37 years failing to turn up.

The Harelip Sucker

The oldest disappearance here, the least disputed, and the owner of a name that would never survive a modern naming committee. The harelip sucker was last collected in 1893 and is generally regarded as the first North American freshwater fish known to have gone extinct in modern times.

What makes it different from everything else on this page is that it was not some fragile endemic 4clinging to one spring. It ranged across clear streams in Ohio, Indiana, Kentucky, Tennessee and Georgia, and it still vanished inside a few decades as deforestation and agriculture filled those streams with silt. The fish hunted by sight, and the water stopped being water you could see through.

Nobody targeted it, nobody profited from it and nobody noticed until it was already over, which is the pattern for every entry here and the reason these losses cluster in the decades when American land use changed fastest.

The Desert Springs Casualties

The American Southwest has lost more fish per square mile than anywhere else in the country, and the mechanism is almost always groundwater. Desert springs support fish found nowhere else, sometimes in a single pool, and once you pump the aquifer feeding that spring the fish has precisely nowhere to retreat to.

The Tecopa pupfish, from hot springs in California's Mojave, holds the bleak distinction of being among the first species removed from the endangered list because it had gone extinct rather than recovered, which is not what anyone had in mind when they designed the delisting process. The Las Vegas dace and the Ash Meadows killifish went the same way.

The Fish With Better Lawyers

The Devils Hole pupfish is the counterexample and the reason the whole category gets any attention at all. It lives in one water-filled cavern in Nevada, its entire global population has at times been counted in the dozens, and it is still here for one reason: in 1976 it won at the Supreme Court.

The ruling limited groundwater pumping around Devils Hole to protect the fish's habitat, which makes this inch-long desert minnow the owner of better legal representation than most American small businesses. Every other species on this page needed the same thing roughly forty years earlier and did not get it.

The Shortnose Cisco Came Back

One entry has moved in the other direction, and it is the reason to handle the word extinct with care. The shortnose cisco, a deepwater Great Lakes whitefish, had not been recorded since 1985 and was comfortably presumed gone. Then a USGS survey in 2022 pulled three of them out of Lake Superior.

The findings went to the Lake Superior Technical Committee and a preprint appeared on bioRxiv in April 2025, and two caveats apply: the work has not completed peer review, and USGS declined interviews pending publication. But three fish is three fish, and a species written off for 37 years had apparently been down there the entire time, unbothered by its own obituary.

Why Freshwater Fish Keep Losing

Marine fish are difficult to drive extinct because the ocean is connected, and a population under pressure in one place can be topped up from another. A freshwater fish lives in whatever creek, spring or lake it was born in, and if that water changes it has nowhere to go and nothing to rescue it.

Then add specialization. The species here were mostly endemics with absurdly small ranges: one creek, one riffle, one spring system. A fish restricted to a single riffle in a single Ohio creek can be eliminated by one bad decade upstream, and every healthy stream elsewhere in the state is no help whatsoever.

Then add detectability, which is the Maryland darter's whole defense. Small bottom-dwelling nocturnal fish are hard to survey even when abundant, so for a two-inch creature that hides under rocks at night, absence of evidence and evidence of absence are not remotely the same document.

What Actually Killed Them

Four causes account for nearly every fish here, and none of them is fishing. Siltation is the most common, as deforestation and row crops push soil into clear streams and bury the gravel that riffle species feed and spawn on. Groundwater withdrawal accounts for the desert species by removing the spring rather than the fish. Industrial discharge and agricultural runoff take most of the rest, and dams finish up by chopping whatever survives into populations too small to persist.

The common thread is that all four are side effects of something else entirely. Nobody set out to eliminate these species, nobody made money from their absence, and nobody was watching closely enough to intervene, which is exactly why nobody noticed in time.

The Honest Status

Put it together and the list refuses to sort into alive and dead. The Scioto madtom and San Marcos gambusia are formally extinct as of October 2023. The harelip sucker has been gone since the 1890s and nobody argues. The Maryland darter is extinct according to the IUCN and endangered according to the US government, with both positions defensible and neither side budging. And the shortnose cisco sat in the extinct column for 37 years before somebody hauled three of them out of Lake Superior.

Which suggests the right way to read any of these announcements. Declaring a species extinct is a decision about evidence rather than a statement of fact, and every so often the evidence turns up alive, in a lake, having ignored the paperwork entirely.