Hell Bent for Hellbenders
May 01, 2019 12:08PM
My exploration of Pennsylvania waterways for the giant, yet elusive, Eastern hellbender salamander began some fourteen years ago with a training dive in Loyalsock Creek in mid-November. My wet suit offered little protection against the bitter cold and I shivered endlessly as I waited for the instructor’s call to dive thirty feet down to the creek bottom. I had paid for this experience because I was told I might see a hellbender, but the opportunity I was hoping for did not materialize. In subsequent years, I acquired the ability to find these amazing salamanders with relative ease and have become something of an expert on the ecology of a unique amphibian that few Pennsylvanians will ever see.
Eastern hellbenders are giants of the salamander world. They can attain lengths of up to twenty-nine inches, but very few reach such a massive size. Comparing a hellbender to the common red-spotted newt or red-backed salamander is like comparing apples to oranges, as the hellbender is only distantly related to those more familiar amphibians. They are more closely related to the giant salamanders of China and Japan. The hellbender is clearly a descendent of those Asian titans, who sometimes attain lengths of four or five feet, and whose evolutionary history clearly had them living in North America over ten thousand years ago. But advancing glaciers and an inhospitable climate took their toll on the giants, leaving the hellbender as the sole North American representative, one whose fossil history shows it lived at the same time as other megafauna such as the woolly mammoth and saber-tooth tiger.
For the past eleven years, I have been studying the hellbender in streams and rivers of the state’s north country, including Pine Creek. Difficult to find, the giants secure themselves beneath rocks of massive size and rarely venture out to feed or find mates. They are sit-and-wait predators that grab a passing food item, almost always a crayfish, by using a powerful suction-feeding mechanism. The hellbender “vacuums” a crayfish into its mouth, then swallows the crustacean whole. One might suppose that the armored skeleton of a crayfish should not be digestible, or very palatable, but the hellbender’s tough gut can process every last bit of it for needed nutrients and energy.
Hellbenders live a solitary lifestyle inside gravelly chambers that they excavate beneath boulders in places where the current is hard and fast. In early fall, the females are enticed to deposit long strings of pearl-like eggs inside the males’ chambers, where the males then fertilize them. The females depart after the egg-laying, leaving the male, or denmaster, with the responsibility of tending the eggs. For six to eight weeks, the embryos develop slowly and then, in flurry of activity, the tiny, gilled, larvae with bright yellow bellies burst through the outer membrane to join siblings huddled in a corner of the chamber. The job of the denmaster is not finished until mid-spring, when the youngsters move out to seek a shelter of their own and to forage for stream insects, or perhaps become food for fish, crayfish, or even larger hellbenders. The larvae will wander the maze of stream rocks, feeding and growing until they attain maturity at age six or seven.
As adults, they are at little risk from predators other than humans, who sometimes kill them not realizing how harmless they are or how valuable they are to stream and river ecosystems. Sportsmen in north central Pennsylvania had a tradition of “hellbender hunting” that reached its heyday in the 1930s when they sought to rid streams of the perceived enemy of their beloved trout, not knowing that hellbenders dine solely on crustaceans. Fortunately, the hunts were not entirely successful.
However, the hellbenders are today on the verge of extinction in many parts of Pennsylvania, and throughout their North American range, extending from New York through the central Appalachians to northern Georgia. To the west, the Ozark hellbender, a variant of the Eastern hellbender, has been designated by the U.S. Fish and Wildlife Service as an endangered species, and I would argue that the Eastern hellbender should be listed as well. Since the mid-1800s, Pennsylvania streams have been poisoned by mine and tannery discharges, stream channels straightened and rocks removed to float timber, and stream rocks slowly but progressively covered with the sediments released by logging and agricultural activities. While today we have improved water quality, the large-rock habitat that this animal favors remains buried beneath thick layers of stream sediment.
Even so, the underlying cause for the recent declines and local extinctions of hellbender populations is not easily attributed to anthropogenic stream degradation. Instead, disease seems to be a likely culprit, but we do not yet know if it is the destructive skin fungus that has been killing off amphibians across the globe or some as-yet unidentified virus. Whatever the cause, the stress of poor water quality, lack of rock cover, and invasions by non-native rusty crayfish may also be contributing factors.
The hellbender will need our assistance in order to reestablish itself in Pennsylvania waterways. With the aid of high school and college students, I have been installing “bender huts” in area streams. The concrete huts serve as shelter for the salamanders and provide us with a means to collect fertile eggs and hatchlings. In October 2014, 100 hellbender eggs and larvae from north central Pennsylvania were placed in the care of the Wildlife Conservation Society’s Bronx Zoo in New York. In August 2018, at age three and a half, the juveniles were released into a historic hellbender stream. Monitoring is now underway to assess the success of this nascent reintroduction project. High school students with the Chesapeake Bay Foundation’s Student Leadership Council are being recognized for writing a bill designating the Eastern hellbender as the official Pennsylvania state amphibian. The bill has been voted out of Senate committee and is awaiting further action by state legislators and the governor.
If you see a hellbender in a Pennsylvania stream, be sure to give this animal the respect it deserves and let it be. If you would like to share your experience with these amazing giants, or for more information, visit lycoming.edu/~petokas.