By: Donna Morelli, Chesapeake Bay Journal
A small fish that once lived in freshwater streams throughout the Chesapeake Bay watershed got a lucky break in a Pennsylvania creek this year.
When Donegal Trout Unlimited restored the Lancaster County creek to protect trout and other sport fish, the rarely seen Chesapeake logperch showed up for the party.
“We build it and they come,” said Greg Wilson, a longtime member of Donegal Trout Unlimited. “When they electrofished the creek after restoration, there were lots of trout and lots of logperch.”
A few months after planting the last tree on the restored banks of Peters Creek, a second electrofishing trip-- which samples fish populations by stunning them with a mild electric charge-- turned up about nine of the little olive fish with orange bands. Prior to the restoration, sampling produced no logperch at all.
The Chesapeake logperch, with an average length of just 4 inches, once swam in the streams of Pennsylvania, Maryland, Virginia and the District of Columbia, including a few direct tributaries to the Bay.
Now, the logperch is listed as threatened in Maryland and Pennsylvania and is being evaluated for national protection under the U.S. Endangered Species Act.
Chesapeake logperch disappeared from the Potomac River basin by the 1930s. Their range in the Susquehanna watershed has decreased but persisted.
According to the U.S. Fish and Wildlife Service, they were once found in the river as far north as Columbia, PA, but since 1842 they haven’t been found upriver of the Conowingo Pond, a reservoir formed between the Holtwood and Conowingo dams.
Most of the logperch found in both Pennsylvania and Maryland are in the lower reaches of streams that empty into the Conowingo Pond.
A Fish and Wildlife report cites water pollution and loss of habitat as reasons for the decline. Sediment is particularly harmful to logperch habitat.
Using its conical nose, the fish roots around stones on stream bottoms to jostle out a meal of invertebrates. Silt that settles into the cobble smothers the small living spaces of the logperch’s food.
The species also faces threats from an increasing number of voracious, invasive species: the northern snakehead and flathead catfish.
“We would like to develop a conservation strategy for this fish, expand its range and strengthen the population in the hopes that it doesn’t have to be listed as an endangered species,” said Jennifer Bukowski, a fisheries biologist with the Fish and Wildlife Service in State College, PA. “The Chesapeake logperch falls into a category of species being considered for listing but for which there is little information on status and threats.”
The irony of finding the fish in Lancaster County’s sediment-laden streams isn’t lost on Bukowski or her colleagues. They are the same streams targeted for Bay cleanup efforts because of the county’s disproportionate contribution to the state’s nutrient load to the Chesapeake Bay.
Even so, a small number of streams still contain sections with clean water and cobblestone bottoms that attract logperch.
Techniques employed along those streams for reducing water pollution-- such as fencing livestock out of streams and installing practices on farms to stem the flow of sediment and manure-- also improve habitat for both logperch and trout.
“What’s good for the logperch is good for the trout,” said U.S. Fish and Wildlife Service biologist Adam Smith, who has worked on stream restorations in Lancaster County since the 1990s. “They like clean water, no sediment and cover, the same as trout.”
Listing the logperch under the U.S. Endangered Species Act would place restrictions on disturbing streams, even for restoration purposes.
But its listing is far from assured. There are more than 300 species of plants and animals being considered for protection under the act that are awaiting decisions by 2023. The lengthy process starts with filing a petition to suggest the species be listed. The next step is to gather data to defend the petition.
Bukowski said a few studies “are in the works” and that the Fish and Wildlife Service is conserving logperch habitat with the hope that additional protection won’t be needed.
The agency is poised to restore more stream habitat in Lancaster County with partners like the state’s Fish and Boat Commission, Trout Unlimited and the county’s Conservation District.
The U.S. Fish and Wildlife Service and Conservation District recently finished a large restoration project in the Octoraro watershed, where Amish farmer L. Michael Kaufman asked for help to stabilize the eroding banks of a stream.
“When we first got there, there was not much habitat,” Smith said. “The stream had lots of sediment from lack of pasture management. But when we explained to Mr. Kauffman about the logperch, he said, ‘hey, I can do better than this.’ Private landowners are key if we are to restore habitat for the Chesapeake logperch.”
The joint project restored 3,900-linear feet of streambank by regrading it to a level similar to the surrounding land and creating a natural floodplain. Logs and stones were used to create pools and riffles, which oxygenate the water and emulate natural streamflow.
Mud sills, long log structures along the edges of the stream bed, were installed to provide cover for fish and reinforce the banks. Native trees, shrubs and grasses have been planted along the banks to filter runoff and help hold soil in place during storms.
The Fish and Wildlife Service is partnering with Donegal Trout Unlimited on more of these projects, including one on Fishing Creek in southern Lancaster County.
The Fishing Creek project was originally focused on improving trout habitat, but Smith said that it will be reviewed for ways to make a comfortable niche in the ecosystem for the logperch.
“Implementation so far has been good for the trout and the logperch,” Smith said. “But if we had to choose, we would give the logperch some priority.”
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(Reprinted from the Chesapeake Bay Journal.)
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