Hurricane Helene Took a Toll on Virginia’s Eastern Hellbender Populations

Some of the wildlife most impacted by Hurricane Helene in September 2024 are some of the least visible—the eastern hellbenders. While the game fish populations seem to have weathered the storm with minimal detrimental effects, the eastern hellbenders appear to have suffered greater impacts, as far as biologists can tell at this point.

DWR’s Statewide Herpetologist, J.D. Kleopfer, has spoken with Dr. William A. Hopkins, a professor at Virginia Tech who is working with Kleopfer on hellbender conservation and has assessed some of the damage to hellbender habitats. “He told me that there were streams that were only a couple feet deep that are now six feet deep. He said some streams are completely gone; they’ve just completely have changed their course,” Kleopfer said. The Clinch and Holston rivers in southwest Virginia were most impacted by Helene, and they’re also where Virginia’s hellbender populations primarily exist.

Even before Helene, conservation work had been underway for the eastern hellbender populations in the Holston and Clinch rivers in Virginia. Hellbenders are listed as Tier 1a (Critical Conservation Need with “immediate and intense management action” required to prevent extinction) species of Greatest Conservation Need in the Virginia Wildlife Action Plan, and in December 2024, the U.S. Fish and Wildlife Service (USFWS) submitted a proposal to list the eastern hellbender as federally endangered. Threats to hellbenders include reduced forest buffering of the riverbanks and human interference with their nesting sites, which are under large, flat rocks on the river floor. Hellbender nesting season begins in late August and early September; the male hellbender guards a nest that contains hundreds of eggs under a rock until they hatch in April.

For the last decade, DWR and Virginia Tech have been working together on building and placing artificial nest boxes on the bottom of the rivers —large concrete boxes that mimic the under-rock space that hellbenders use for nesting. The boxes provide hellbenders with nesting sites that aren’t affected by human disturbance of the river bottom.

Kleopfer noted that he and the Virginia Tech researchers had identified and were monitoring 58 nests in early September 2024. “We had our best nesting year so far,” he said. “But they were probably all wiped out because the hurricane hit right after nesting season. If there were eggs in those boxes, they would have been washed out by the river flow, and the adult hellbenders were trapped in boxes or on the river bottom by sediment.” Hellbenders in natural nesting sites would have been affected as well, as heavy river flow would have washed out the site, and possibly washed the adult animals miles downstream.

“This is going to be one of those events that occurs in the history of the species that will need decades upon decades of recovery,” Kleopfer said. “It may be 100 years before these populations recover. This is a long-lived species in the wild—they potentially live 30 years in the wild—so their abilities to recover are pretty slow. If you turn back the clock just 500 years, recovery wouldn’t have been that challenging in the sense that the landscape was so much more intact and less impacted by human footprint. But now, they have to not only deal with the recovery of this storm, but they have to do it in the context of what the landscape looks like now, which is just going to slow it down even more. I’m hopeful that they’ll recover, but it’s going to be a long time.”

Luckily, Kleopfer and Hopkins have the nesting box technology and strategies already in place to be able to begin restoration efforts before the 2025 nesting season. In addition, Hopkins and his team at Virginia Tech were awarded a $1-million-dollar from the U.S. National Science Foundation and the Paul G. Allen Family Foundation for hellbender conservation work. “This grant will really allow us to be able to implement some real on-the-ground conservation actions and hopefully move the needle on recovery for this species,” Kleopfer said.

The grant focuses on research into another population threat for eastern hellbenders—a scenario when the male hellbenders actually ingest the eggs they’re guarding. “We don’t know why,” Kleopfer said. “There’s plenty of food out there for them and all their body conditions are in great shape. They seem healthy. So, we think it might have to do with dissolved oxygen levels or something along those lines. The grant work will try to untangle all of this and find a solution.”

One solution is to capture fertilized eggs, hatch them out in the Fralin Biomedical Research Institute lab at Virginia Tech, and then re-introduce the hellbender larvae to the nest boxes once they’re past the point when the adult male would eat them. “Hopefully, that will allow for these animals to develop and start to grow into adults,” Kleopfer said. “This will complement efforts that are going on in stream restoration—creating more vegetative buffer along these streams. Removing that vegetative buffer along these streams creates a whole suite of problems, from sediment runoff to declines in dissolved oxygen levels, and changes in the macro fauna, so there’s a whole cascade of events that happens. There’s a lot of conservation efforts going on out there to restore these riparian corridors. While that’s going on, we want to augment these populations to boost them along until they start to recover. Hopefully, in the meantime, we can also identify exactly what is causing this phenomenon.”

It will take some time for Kleopfer and the Virginia Tech researchers to fully understand Helene’s impact on the hellbender populations of the Clinch and Holston rivers, but come spring, they’ll be out in the waters collecting data and making a plan to help ensure that the 2025 nesting season, and those further into the future, are as productive as possible.