Monday, July 29, 2019

A Shot of Salvation for Chesapeake Logperch

Chesapeake Logperch
Scientists see early success in breeding effort to help save Chesapeake logperch
In a mad dash to keep the Chesapeake logperch from being placed on the federal endangered species list, the tiny fish is certainly doing its part.

In an underwater roundup of sorts, 28 logperch were netted in late March from three tributaries to the Susquehanna River in Lancaster County, PA, just north of the Maryland line. In an experiment with plenty of doubts, those 28 have multiplied to about 1,500 in propagation fish tanks in Tennessee and at Penn State University.

The plan is to reintroduce logperch into one southern Pennsylvania stream this fall, with later stockings possible into up to seven lower Susquehanna tributaries in Pennsylvania from the Holtwood Dam to Harrisburg. That’s an area where the fish were once native but have disappeared.

It’s a rare experiment. The relatively recent discovery of the fish as a distinct species caused fisheries agencies in both Pennsylvania and Maryland to reassess its status. Both declared it threatened in their states.
Maryland DNR's Jackie Sivalia, Matt Ashton, and Megan Davis,
 a Chesapeake Conservation Corps intern, survey for Chesapeake
 logperch in Harford County, MD using seine nets.
Are we worried about a genetic bottleneck here, starting a population from such a small sample?
“There has been quite a lot of work done in the last 10 years or so trying to restore fishes to their habitats, but there are not many restoration projects of this magnitude with a species that has not been federally listed,” said Jay Stauffer, a distinguished professor of ichthyology at Penn State. “To try to prevent a species from being federally listed is pretty unique,”

But first, a seed stock was needed. To make the captured fish feel right at home, researchers scooped gravel and sand from the streams where they were found. They even collected rocks that the members of the darter family flip over with their piglike snouts to look for aquatic insects. They are known for flipping rocks. The elements from their home stream were combined in the propagation tanks, where pumps replicated the current.

Apparently, the fish indeed felt right at home. They reproduced so fast that their fecundity had to be cut off after three weeks for fear they would overwhelm their tanks. The fish were divided between Penn State and rearing facilities in Tennessee run by the nonprofit aquaculture group Conservation Fisheries, Inc. so that an unforeseen accident or disease wouldn’t wipe out the entire population.

Ripe with that success, the next phase of the four-year plan has been expedited. This summer, teams will snorkel and scuba dive in candidate streams, checking stream-bottom habitat, flow and water temperatures in search of ideal homes for the juveniles. The effort will be aided by an underwater drone attached to a 300-foot tether that will send back a deepwater video of the terrain.
I'm happy that they've done this, but it should not be considered a big deal. One grad student who cared could have done this in their spare time. And sold the spare fish for aquaria.

Previous post on the Logperch

The Wombat has Rule 5 Sunday: Claudia Cardinale raring to go at The Other McCain.

No comments:

Post a Comment