Animals that disappeared from some rivers because of pollution, dams and overharvesting are getting a new lease on life that could have ripple effects for other wildlife and for humans.
COFFEY COUNTY, Kansas – On a warm day last spring, wildlife biologist Trevor Starks squatted in a few feet of water and felt the riverbed with his hands in search of one specific mussel species.
Starks wanted to find native, endangered Neosho muckets. More than 600 of them had been released eight months earlier at this spot on the Neosho River, about 60 miles south of Topeka.
After about an hour and a half of searching, Starks held one of the young mussels in his hands.
“This is the most exciting, rewarding part of the job,” said Starks, who works for the Kansas Department of Wildlife and Parks.
He measured the small creature, about the size of a ping pong ball. And he wrote down the number that had been engraved onto it at the federal hatchery where it was born.
Then Starks released it back into the river. He hopes it could start reproducing in the next few years.
The Neosho mucket is one of 21 imperiled aquatic species — including fish, mussels and one kind of turtle — that Kansas aims to help.
Hear Starks tell the story on the November episode of Up From Dust, the Kansas News Service’s environment podcast.
These animals are reeling from the impacts of overhunting, pollution, dam construction and other human activities. Yet some of the dangers these animals once faced have eased up, meaning scientists see hope that specific species could increase again with a little help from humans.
For example, the mussel-harvesting industry that once ravaged the Neosho River and other waterways is now illegal. In Kansas, commercial harvest hasn’t been allowed for more than 20 years.
Also, the 1972 Clean Water Act regulated many pollutants that were killing off river wildlife. Although Kansas rivers continue to face pollution problems, water quality has in many cases greatly improved.
“What we’re trying to do here is restore a cog, a piece of this machine, of the ecosystem back to its place,” Starks said, using rare Neosho muckets as an example.
The last time someone recorded them living in the Neosho River was in the mid-1990s.
The species has disappeared from most of its range. In 2013, the federal government concluded the mussels were endangered.
Kansas wants to help restore healthy populations and someday make it possible to remove the animal from the Endangered Species List.
Losing puzzle pieces
Mussels filter water. Each one filters gallons of it daily. When sections of a river are lined with healthy mussel beds — beds that can have thousands or tens of thousands of mussels each — all this filtering adds up.
“They’re taking bacteria, excess nutrients,” Starks said. “If you took every mussel out of this river — and went and visited water treatment facilities along the Neosho River — I’d imagine that water treatment would get a lot more expensive if you didn’t have mussels in the water.”
Like many Midwest rivers, the Neosho River doesn’t have as many mussels as it once did, nor as many kinds.
In Kansas, 8 mussel species have disappeared. Forty remain, but more than half of those species are suffering to the point that they’re now under various levels of state or federal protections.
When a species disappears from an area, scientists call it a local extirpation. Across Kansas and the country, different areas have lost different species.
Wildlife biologists and ecologists worry about the potential cumulative effects of these missing puzzle pieces.
A native river mussel that disappears was not only filtering the water but also feeding river otters, raccoons and other predators. A turtle that vanishes was dispersing plant seeds and eating carcasses.
“At some point, we lose enough species and the ecosystem goods and services — water filtration, clean air, clean water, pollination, all of those things that intact environments do for us — we could lose that,” Starks said.
Where did the mussels go?
Old descriptions of mussel beds in Kansas paint quite the picture.
“They talk about some of these beds where you couldn’t take a step without stepping on mussels,” he said. “Like there was more mussel than there was gravel almost.”
Such spots still exist, but aren’t nearly as common as they once were. Some contributing factors, such as climate change and invasive species, pose ongoing problems. Other contributors were historic.
In the late 1800s, for example, mother-of-pearl became the focus of a major industry.
For several decades, factories positioned along Midwest rivers turned mussel shells into clothing buttons and other items at a stunning pace.
For example, a single factory on the Neosho went through 18 tons of shell in one week in 1922, according to A Pocket Guide to Kansas Freshwater Mussels, co-written by Edwin Miller, the former endangered species program coordinator for the Kansas Department of Wildlife and Parks.
After that industry waned, the second half of the 1900s brought another reason to pull freshwater mussels from the water: the cultured pearl industry.
This commercial use involved placing pieces of mussel shells into oysters, which would then coat the pieces with mother-of-pearl and form cultured pearls.
Kansas exported more than 2 million pounds of mussels as recently as the 1990s, according to the Pocket Guide to Kansas Freshwater Mussels.
Kansas hasn’t allowed commercial mussel harvest since 2003.
Industrial pollution posed a similar problem, particularly before the 1972 Clean Water Act. Discharges of chemicals and sewage could wipe out many animals at once.
The effects were compounded by widespread construction of dams in the 1900s. Although useful to humans, these posed new problems for many aquatic animals.
Before then, if something caused a fish or mussel to disappear locally from one stretch of river, other members of the species would eventually show up there again.
“Well, now they can’t,” Starks said. “If you’ve seen the size of John Redmond Dam (on the Neosho River), you know that a fish and a mussel isn’t moving over that anymore.”
Many rivers are in this situation. Animals have disappeared from some segments and can’t return.
“It’s just kind of a long, drawn out micro-extinction going on in different stretches of the river,” Starks said.
This is why wildlife biologists — with help from a federal hatchery — started releasing young Neosho muckets.
“These mussels will never be back here without human intervention,” he said.
The plan for action
State biologists hope it’s possible to put back some of the puzzle pieces that went missing from certain rivers or from stretches of those rivers.
“ We think there are conditions that have gotten better in certain stretches,” Starks said, “that can sustain some of these animals that were taken out.”
But to restock rare fish, mussels and turtles, Kansas needs permission from private landowners who may be skeptical of regulations related to rare species and fearful of potential legal liabilities related to having them around.
This is why Kansas and the U.S. Fish and Wildlife Service are trying a new approach.
In 2021, Kansas became the first state with a statewide program meant to help win over assistance from landowners for rebuilding populations of a raft of imperiled species. North Carolina became the second in 2022.
Kansas is focusing on 21 aquatic species, including 10 fish, 10 mussels and the alligator snapping turtle.
Staff from the Kansas Department of Wildlife and Parks find good places to release specific animals into their historic ranges.
Landowners who say yes get liability protections in case a rare animal were to get hurt by accident on their property while landowners are doing legal activities such as farming and ranching.
At first, Starks wondered if any landowners would sign up.
“Going up to a farmer and slapping an agreement on their desk and saying, ‘Hey, do you want to sign an agreement with the federal government and let us put endangered species on here?’” he said. “I was really skeptical that that was going to work.”
Yet each landowner he has approached has ended up saying yes. The key, he thinks, is having thorough, transparent conversations about what Kansas is trying to achieve.
So far Kansas has nearly 20 agreements in place with landowners to release imperiled mussels, fish or turtles on their properties.
The Neosho muckets are two years old when biologists release them, which is almost old enough to reproduce.
“The folks at the hatchery tell me that these get sexually mature at age three,” Starks said.
That means Starks and his colleagues hope that in some years, they could start finding young ones in this spot that aren’t engraved with hatchery numbers. Those would be born in the wild, in an area where no one had recorded one alive for 30 years.
“That’s the big, long end game, is to find a self-sustaining population here again,” he said. “That’s the dream.”
Celia Llopis-Jepsen is the environment reporter for the Kansas News Service and host of the environmental podcast Up From Dust. You can follow her on Bluesky or email her at celia (at) kcur (dot) org.
The Kansas News Service is a collaboration of KCUR, Kansas Public Radio, KMUW and High Plains Public Radio focused on health, the social determinants of health and their connection to public policy.
