West Virginia’s research into muskellunge mortality has spread to other states.
The project, designed to learn how water temperature affects muskies that have been hooked and released, initially focused on fish in West Virginia and Virginia. Since then, North Carolina, Maryland and Wisconsin have signed on.
Jeff Hansbarger, the Division of Natural Resources biologist who coordinates the study, said those other states are providing data researchers in the Mountain State would have had trouble getting.
“They’re helping out with the portion of the project that deals with muskies in ponds,” he explained. “This is big because muskies are low-density fish, and in a hatchery situation with adult fish in a pond, there’s only so many you can have.”
The research focuses on three environments — lakes, rivers and ponds. Biologists implanted radio tracking transmitters in the abdomens of 90 muskies in West Virginia’s Stonewall Jackson Lake and in Virginia’s James River. Anglers who catch and release the fish during the height of summer are being offered rewards to report the catches.
“We expect some of those fish to perish, but we have to have that to find out what we need to know,” Hansbarger said.
Specifically, they want to know at what water temperatures caught-and-released muskies begin to die in significant numbers. The study’s findings should help to settle a long-term argument among anglers, some of whom continue to fish for muskies in warm-water conditions and some of whom stop fishing at the onset of summer.
Hansbarger said the research got off to a slow start because the COVID-19 pandemic kept biologists from capturing enough muskies to provide an acceptable data sample.
“Now we have a total of about 90 fish at both locations,” he added.
The pond component of the study initially focused on just one location — West Virginia’s Palestine Hatchery. Due to the pandemic, electrofishing crews were able to collect just 13 muskies.
“The idea was to catch half the fish and not fish for the other half as a control measure,” Hansbarger said. “Having them in a pond allows us to monitor the temperature and conditions under which the fish are caught, and to monitor the fishes’ long-term health.
“When the water temperature maxes out, we drain the ponds, count the fish to see if any of them died, and release the rest back to the waters we captured them from.”
This year, with COVID-19 no longer constraining sampling efforts, crews were able to collect 40 fish for the two ponds at Palestine. Even with that many fish, Hansbarger wondered if enough data would be collected.
That’s where the other states came in.
“Those other states had more hatchery space, and it was easier for them to set up ponds with muskies in them,” Hansbarger said. “We’ll get data from Wisconsin, which is in the heart of the species’ home range, and we’ll also get data from West Virginia, Virginia, North Carolina and Maryland, which are on the edges of that home range.”
Although he said he doesn’t want to fully “let the cat out of the bag,” Hansbarger offered glimpses into some of the study’s preliminary findings.
“There hasn’t seemed to be much [mortality among muskies hooked in warm-water conditions], but this is only the first year,” he said.
“We had one mortality at Stonewall, but that fish was hooked in the gills and wouldn’t have survived anyway. A few fish died in the James River, but there were no signs the fish had been hooked. There just seems to be a lot of natural mortality on that river, with fish going over low-head dams and things like that.”
He said the findings from last year’s cohort of muskies kept at Palestine seemed to indicate that muskies feed much less often when water temperatures rise well above their comfort level.
“During the dead of summer, the muskies in the ponds sort of shut down,” he added. “[Graduate student] Taylor [Boothe] took a very small percentage of what was put in there.”
Information from this year’s summertime catches, which are ongoing, will be factored into the multi-year study’s database.