Eastern Hellbender Proposed as Endangered Species Addition

What's a Hellbender?

Meet the Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis). This salamander has a large, flat head; small eyes; a wide neck and wrinkled body. With four front toes and five hind toes, adults walk about the stream or river bottom looking for crayfish, insects, and small fish. Hellbenders respire cutaneously - that is, they breathe through their skin and they are primarily nocturnal. They do have lungs and can use them for respiration under certain conditions. Eastern hellbenders are not well adapted to low-oxygen conditions and may be seen exhibiting rocking behavior to increase oxygen transfer across the skin. They are entirely aquatic.

Adult hellbenders typically live alone under large slab rocks. From late August to early October, female hellbenders deposit 300-450 eggs in a clutch under a nest rock. Males fertilize the eggs. A single male hellbender cares for and defends the eggs until they hatch in 45-75 days. Estimates suggest that hellbenders can live at least 25-30 years in the wild. They inhabit fast-flowing, cool, and highly oxygenated perennial streams with boulder, cobble, and gravel substrates. These salamanders often live for a long time under the same large rock; researchers have found the same individual under the same rock over several years. When people make stacked rock constructions, they likely disturb the habitat of these threatened animals. 

Why are Populations Declining?

Eastern hellbenders occupy streams of orders 2 through 8. Stream order is a way to classify streams within a watershed based on their position. The smallest headwater streams are assigned the lowest order. 

The Eastern Hellbender currently occupies four evolutionarily distinct genetic lineages in their range. These lineages, identified by Hime et al., have been used to delineate four Adaptive Capacity Units. They are the Missouri, the Ohio River-Susquehanna River drainages, the Tennessee River drainage, and the Kanawha River Drainage. Found originally across 15 states from Mississippi to New York, 76% of all 626 historical hellbender populations are now thought to be extirpated or declining! These declines are expected to continue over the next 25 years. Therefore, the US Fish and Wildlife Service has proposed adding the entire Eastern Hellbender subspecies to the endangered species list under the Endangered Species Act (ESA). 

According to the US Fish and Wildlife Service, water quality degradation, habitat destruction and modification, and disease all contribute to the hellbender’s decline, but the factor most impacting populations is sedimentation. Identified in every major river system in the hellbender’s range, it derives from multiple sources: agriculture, silviculture, oil and gas development, residential development, off-road vehicles, impoundments, instream gravel mining, and road construction. Sedimentation consists of fine soil particles, which modify aquatic habitats by increasing turbidity, reducing light penetration, increasing water temperature, and filling in spaces among the coarse rocks important to hellbender habitat. Sediment also degrades habitat for macroinvertebrates, which are an important source of food for larval helbenders. It can suffocate eggs, and because some pesticides bind to soil particles and become suspended in the water column, the hellbender’s permeable skin absorbs these substances. 

What Can I Do to Reduce Sedimentation?

Employ strategies to prevent soil from entering our waterways. Minimize soil disturbance and keep soil covered with vegetation or mulch. If soil must be disturbed,  implement erosion and sedimentation controls, slow the flow of water, and trap sediment before it reaches waterways. Sweep soil from hard surfaces; don't hose it into a storm drain. Consider rain gardens or no-mow lawn mixes to reduce runoff.

If your property lies beside a body of water, still or flowing, plant appropriate trees and shrubs along the edge. This "riparian buffer" – a strip of native vegetation along the banks filters pollutants, reduces erosion, and prevents runoff from reaching the waterway. The bigger the buffer, the better!

Report soil disturbances in areas where erosion controls have not been implemented to your county Conservation District office.

References: 

United States Department of the Interior, Fish and Wildlife Service, Northeast Regional Office. July 2025. Northeast Endangered Species Determination Key Standing Analysis. Version 2.0.   93 pp. 

US Fish and Wildlife Service. 2024. Species Status Assessment Report for the Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis) Version 2.1.   96 pp.