Eastern Hellbender (Cryptobranch a. Alleghenian) is not as scary as the name suggests. They're actually pretty cute if you can get past them salamanders slimy, slimy skin that has earned it nicknames such as “sniveling otter” and “climbing lizard.”
Although hellbenders can grow up to two feet in length, amphibians are notoriously elusive and prefer to live under large, flat rocks in the well-oxygenated waterways that snake through the Appalachians and the Ohio River basin. They are also becoming increasingly difficult to detect as their numbers decline due to environmental problems. Based on a recent environmental study covering 90 sites along 73 rivers, researchers from the University of Kentucky now believe they have identified one of Hellraiser's major problems. They are losing their habitat due to increasingly murky, sediment-filled waters, according to a study published in the journal. Freshwater biology.
Study co-author and biologist Steven Price said catching a hellbender is quite difficult, even if you're not doing research funded by the U.S. Department of Natural Resources.
“They live under large rocks. It takes time, people and care to lift them safely,” he said in a statement. accompanying statement from the university. “When you see it in the wild in Kentucky, it’s something special.”
Instead of spending countless hours wading through rivers in hopes of finding their magicians, Thomke, Price and their colleagues instead relied on Monitor evidence of living organisms known as environmental DNA (eDNA). After collecting and filtering river water, the team tested samples for the presence of a gene found only in this species. This allowed them to avoid wasting time rearranging massive rocks or catching salamanders. Biologists ultimately found hellbender DNA at 22 sites throughout Kentucky, 12 of which had historical records associated with the animals. They then used statistical occupancy patterns to determine where hellbenders lived and when their eDNA was most easily identified.
“We could clearly link the quality of stream habitat to where hellbender DNA appears,” added study co-author Sarah Thomke. “He brought the science together and showed what field managers can do.”
The team determined that the amphibian's local habitat is a more important factor in determining where it lives than overall water chemistry or land cover. Larger streams lined with more gravel, cobblestone, and bedrock corresponded to more hellbenders. However, their numbers declined when grain and silt began to clog the crevices under the rocks.
“Fine sediment is a big problem,” Thomke explained. “It fills potential nesting sites and small spaces that the larvae use for shelter. Without this space under the rocks, the animals will not be able to reproduce or survive for long.”
They also figured out what time of year is best to try hellbenders. Early autumn, especially during the September breeding season, seems to be the most reasonable time. In early fall, the creatures release additional genetic material, making them easier to detect.
In addition to their uniqueness, the study authors add that hellbenders can act as excellent indicators of ecosystem health. When their populations decline, it often harms other species that prey on amphibians.
“Sarah’s project gives us clear goals for habitat conservation,” Price said. “First, keep sediment out of streams. Then protect and restore rocky beds and forested stream banks. That's how we give this species a chance.”
Fortunately, it appears that the largest Hellbender mapping effort of its kind has not been a complete failure for those involved.
“Seeing a hellbender is incredible, but holding one is next level,” Thomke said.
