MARION, Ohio — A team of Ohio conservationists is dedicated to re-establishing the endangered eastern hellbender, the largest amphibian in Ohio and one of the largest salamanders in the world, in areas it once occupied.
Several organizations are working together to raise hellbenders to release them to the wild. This effort marks an important step in the ODNR Division of Wildlife’s Conservation Plan to reverse the precipitous decline of the species by expanding their range into previously occupied streams and establish multiple self-sustaining populations in Ohio.
Collaboration
The Columbus Zoo and Aquarium, the Toledo Zoo and the Wilds, in Muskingum County, collaboratively are raising hellbenders from eggs collected in eastern Ohio. These organizations have been successful in raising hellbenders from the egg stage to sub-adult stage.
However, as the hellbenders grow they require increasingly more space, exceeding the partners’ holding capacity.
Relocation
The Marion Correctional Institute (MCI) has started an inmate rearing program to increase rearing space and juvenile hellbender survival. Twelve juvenile hellbenders were transferred from the Toledo Zoo to MCI Sept. 26.
“The transfer of the hellbenders to MCI is a significant first step in increasing the numbers of hellbenders available for release,” said R. Andrew Odum, the Toledo Zoo’s curator of herpetology and assistant director of animal programs.
“The preservation of Ohio’s native wildlife is a principal priority for all the partners in this project.”
To date, more than 20 hellbenders have been released into two eastern Ohio streams where hellbenders were once found. These streams were once severely impacted by pollution but have since recovered and are some of the highest quality waterways in the state.
Tracking
Hellbenders were surgically implanted with radio-transmitters to enable biologists to track the animals; data from this project will be used to develop future hellbender reintroductions in Ohio.
As one of the largest salamanders in the world, the eastern hellbender reaches up to 25 inches in length and weighs nearly 3 pounds. With its wrinkled body and tiny eyes, the hellbender is supremely adapted to a life spent mostly under large rocks in rivers and large creeks, where it feeds on crayfish and takes in oxygen through its highly vascularized skin.
The hellbender is an important part of Ohio’s natural heritage, and the presence of this species indicates clean water and healthy habitats.
Previously
A 2006-2009 survey of the eastern hellbender in Ohio determined an 82 percent decline in the relative abundance of individuals in streams where they were found during surveys conducted in the mid-1980s.
In the Ohio watersheds where hellbenders remain, populations consist of only old, large individuals, indicating the lack of successful population recruitment.
Most remaining populations in Ohio do not appear to be self-sustaining, and without intervention, the hellbender will likely disappear from Ohio waterways.
Decline factors
Causes of the decline of hellbenders include excessive siltation, pollution, disease, persecution, collection and impoundments (dams).
The species range from New York to Georgia and west to Missouri and were once found throughout the Ohio River drainage basin, including the Ohio River. Similar population declines have been noted by researchers throughout the hellbender’s range, and the species is considered threatened or endangered in most states.
Funding for this project was provided by the U.S. Fish and Wildlife Service through a State Wildlife Grant, donations to the ODNR Division of Wildlife’s Diversity Program, the Toledo Zoo and the Columbus Zoo and Aquarium’s Conservation Fund.
