Header image: The hellbender is one of the largest salamanders in North America and its populations are plummeting. A male eastern hellbender guards his eggs in an underwater nest box. Photo Credit: Cathy Jachowski.
From VT News | July 15, 2019
With support from the Fralin Life Sciences Institute at Virginia Tech and several other co-sponsors, the ninth Biennial Hellbender Symposium recently held three days of talks, exhibitions, and poster sessions.
The hellbender, Cryptobranchus alleganiensis, is one of the largest salamanders in North America and the third largest salamander in the world after the closely related Chinese and Japanese giant salamanders. Two subspecies of hellbenders can be found along the Appalachian mountains and in the Ozarks of Missouri.
Despite the hellbender’s fearsome appearance, it’s known for paternal care of its offspring, the subject of an ongoing study by symposium co-organizer and hellbender expert, William Hopkins, professor of fish and wildlife conservation in the College of Natural Resources and the Environment and director of the Global Change Center.
In the past decade, populations of the hellbender have plummeted, and researchers are baffled as to why. Although adults can be found in the wild, few juveniles or young adults are found during surveys. Researchers have posited many possible causes: sedimentation caused by deforestation; pollution from fracking in the eastern mountains; loss of habitat due to a number of factors, climate change and agriculture among them; and the onset of the now globally ubiquitous chytrid fungus, a pathogen originating in Asia and spread through the pet trade.
The symposium was founded nearly 20 years ago as a means for researchers from academia, NGOs, zoos/aquaria, and state and federal agencies to gather and exchange information about their findings and the strides they’re making toward understanding the species’ decline and efforts toward its recovery. Professor Emeritus Thomas Pauley of Marshall University and this year’s keynote speaker, said, “I’ve been attending this symposium from the beginning and it has really provided a nucleus of research and community for those working with this species.”
Sometimes, with a species so seemingly secretive and difficult to study, one of the symposium’s best features is the camaraderie and information exchange it provides for researchers.
This year’s panels and presentations featured numerous talks about strategies for helping boost the hellbender’s populations — from a variety of underwater nest box designs to sharing data about the changing nature of the rivers and streams that hellbenders inhabit. For example, several research teams displayed modifications of concrete nest designs that allow researchers to monitor hellbenders in the wild and also serve as a valuable habitat restoration tool. Hopkins’ team has successfully used their box design to conduct innovative studies of the reproductive ecology of this poorly understood species.
Other presentations delved into the ways in which hellbenders are studied and whether or not better techniques might lead to better results in terms of tracking and survivorship. One study in particular by Stephanie Morrison, a graduate student at Missouri State University, looked at how electrofishing, a common technique for surveying fish populations, might be detrimental for hellbenders.
Researchers also discussed the environmental impacts on streams that some of them have been monitoring for decades. Populations in eastern Ohio have dropped 82 percent in the past decade. With the rise of fracking, streams are showing much heavier sedimentation and pollution than in previous years. One fracking company in eastern Ohio self-reported over 70 watershed violations. Gregory Lipps of Ohio State University asked rather poignantly, “Is the original goal of having self-sustaining hellbender populations realistic? Are we just buying time for what we hope is a better future?”
In the face of such alarming signs, the U.S. Fish and Wildlife Service was in attendance to discuss its ongoing assessment of the eastern subspecies and whether it, or any of its distinct population groups, should be federally protected as threatened or endangered. The Ozark hellbender subspecies is already considered critically endangered and received federal protection.
“Such a bleak outlook for the species can be a bit depressing, but this symposium always gives me hope,” said Hopkins. “It is inspiring to see nearly 100 experts gather to compare notes in hopes of saving this species from the brink of extinction. Scientists came to Blacksburg from as far as Japan to help address this conservation challenge. The passion in the room was palpable.”
One thing that was clear from all the talks, posters, and updates given from the hellbender’s range: each population is unique, often responding differently to the same recovery technique that is successful elsewhere. What works well in Missouri may not work as well in North Carolina or New York and no one is sure why. All that can be done is to keep trying, keep innovating on what works and modifying it to specific field conditions.
Pauley encouraged his successors in the study of salamanders never to lose their curiosity or sense of wonder: “Leave no stone unturned. You never know what might be under there.”
~Written by Tiffany Trent