Wrinkled, Rare, and Remarkable

On a cool and foggy September morning, Missouri State Herpetologist Jeff Briggler gently paddles his canoe to a stopping point on an Ozark stream. Taking inventory of his surroundings, checking his data sheets, and surveying the shore, he decides he’s in the right place.

“We have several artificial nest boxes on this stream, and one of them is a fairly consistent box,” Briggler explains. “Since we put this box here 12 years ago, the same male has bred in there 11 times. So, he’s kind of my first representative of the year to look for eggs.”

This is Briggler’s first day of the 2023 fall season searching for hellbender eggs, particularly from the eastern subspecies, which lays eggs earlier than its Ozark relative. Before zipping up his wetsuit, he takes a moment to record some data.

“Even though we’re looking for eggs, I will do a count on the hellbenders I see today, and tally those so we know how many have been observed during the course of the day and at what locations,” he explains.

After noting the location, time, and water temperature, Briggler secures a weighted belt to his waist, puts on a pair of goggles and a snorkel, and dives underwater. He finds no eggs in the nest box but returns from the water holding a hellbender — the largest species of salamander native to North America.

A Creature from the Underworld

The etymology of “hellbender” is unclear, but one theory claims the salamander was named by settlers who noted it appeared to be a creature from the underworld, where “it’s bent on returning.” With their wide, flat heads, tiny eyes, rudderlike tail, and long bodies covered with prominent folds of skin, hellbenders possess a unique appearance. In recent years, it has been tagged with more positive nicknames on social media, including water dog, snot otter, and “ol’ lasagna sides.”

Missouri is the only place in the world where both Ozark and eastern hellbender subspecies can be found. Eastern hellbenders are slightly larger, measuring between 13–23 inches. Ozark hellbender adults average between 10–21 inches. Perhaps the easiest way to distinguish between the two is geographically — Ozark hellbenders are found in south-flowing rivers in the southern Missouri Ozarks, while eastern hellbenders are found in north- and northeast-flowing rivers in the northern Missouri Ozarks.

Tailor-made for an entirely aquatic existence, hellbenders’ flat heads and streamlined shapes reduce water resistance, allowing them to live under flat rocks and bedrock crevices. They’re slow swimmers and often move by walking along the bottom of streams and rivers. Numerous wrinkly folds of 
skin along the hellbenders’ sides provide increased surface area for respiration. Capillaries near the surface of their wrinkly skin absorb oxygen directly from the water. Because they require cool, well-oxygenated, and clean-running water to survive, hellbenders are a major indicator of overall river or stream health.

Rivers in southern Missouri and northern Arkansas once supported up to 45,000 hellbenders. Today, only about 2,000 exist in the world — so few that both Ozark and eastern subspecies have been added to the federal endangered species list. The biggest threats hellbenders face include habitat alteration and degradation, disease, predation, and degraded water quality.

Hellbender Husbandry

In the early 2000s, MDC partnered with the Ron and Karen Goellner Center for Hellbender Conservation, a part of the Saint Louis Zoo WildCare Institute, and other agencies to breed hellbenders in captivity and rear eggs collected from the wild to combat drastic population declines.

“Ron Goellner, our former director of animal care at the Saint Louis Zoo, was a huge advocate for Ozark hellbenders, and he wanted to ensure we were doing something to help these animals,” explained Justin Elden, curator of herpetology and aquatics at the Saint Louis Zoo and director of the Saint Louis Zoo WildCare Institute Ron and Karen Goellner Center for Hellbender Conservation. “The center was later renamed to highlight Ron’s wife, Karen, who was also a champion for these animals.”

Hellbenders require specialized habitats, living only in fast-flowing, cool, and heavily oxygenated streams. Recreating this habitat at the zoo’s herpetarium was crucial in successfully breeding and rearing these animals. Behind the scenes is a fully-functioning, 32-foot-long, constructed Missouri stream, complete with a rock bed, the occasional afternoon rain shower, and the area’s freshest and purest water.

“Water parameters at the zoo have to match what hellbenders need in the wild,” Elden noted. “Our zookeepers are not only taking care of the animals, but they’re taking care of the water they live in because the two are so closely intertwined.”

To ensure proper care for the hellbenders and their habitat in the herpetarium, the zoo employs a team of four zookeepers who exclusively work with hellbenders, conducting daily water quality tests and documenting every detail. An on-site veterinary staff addresses any animal health concerns, and a heating, ventilation, and air conditioning department ensures the herpetarium’s systems have clean, flowing, cool water.

“We literally wrote the book on hellbender husbandry and hellbender care,” Elden said. “This is the largest program like this in existence, but nature was the first to do this. We listened to nature and replicated it at the zoo.”

Once captive-bred larvae reach between 3–8 years old, they are released in their native Ozark aquatic ecosystem. Biologists began releasing a few zoo-raised hellbenders in Missouri in 2008, later increasing the number of released animals to 1,000 or more per year beginning in 2012. Ultimately, more than 12,000 zoo- and hatchery-raised Ozark and eastern hellbenders have been released into their native rivers.

To track the restoration progress, biologists monitor the population status of both wild animals and released animals reared in captivity, as well as locate natural nests within rivers during the fall to collect eggs that can be reared and released in the future.

Most hellbenders existing in the wild and all 12,000-plus released animals have a small chip embedded under their skin that allows scientists to identify the animals in future encounters.

Though many have been released to the wild, most hellbenders are only just now becoming mature enough to breed. Because very few nests with eggs are found each year, capturing the event of a male attending a clutch of eggs is a rare event.

“We’re lucky to find 20 nests in the wild a year and finding a tagged father that was raised at the Saint Louis Zoo was like finding a needle in a haystack,” Briggler explained.

Researchers found that needle in October 2022, when they came across a tagged male Ozark hellbender that was attending a clutch of healthy, well-developed eggs on the Current River. The animal was guarding a total of 128 eggs. Upon a later return to the nest, the eggs were beginning the process of hatching with a father protecting them.

Roughly a year later, researchers found evidence of the first zoo-raised eastern hellbender reproducing in the wild, this time on the Gasconade River.

“Rarely are hellbender nests found on the Gasconade River,” noted Briggler. “Therefore, it was a pleasant surprise to even find a nest, but an overwhelming surprise to learn the father was a released animal.”

Though these two incidents were the first time researchers documented zoo-reared animals reproducing in the wild, Elden does not believe they were isolated incidents.

“I think reproduction has happened with other zoo-reared animals who were not in areas we surveyed, but these two incidents were the first ones we found,” he explained. “And I don’t think it’s going to be the last ones we find — I think it’s going to happen more often, which is huge.”

‘Little Golden Nuggets’

Unlike many species, the male hellbender takes a more active role in breeding. In the fall, he will begin making nests by digging under a large rock and then wait for a female to come and lay eggs in the nest, usually two strands of 100 to 350. The male will spray his sperm on the eggs, and the female will leave. He then guards the eggs, which hatch in four to six weeks, and watches over the babies until they leave the nest in late winter or early spring.

Because hellbenders spend most of their lives under rocks, it’s important to leave rocks where they’re found naturally; hellbender homes can be destroyed when people disrupt their habitat by moving rocks.

To give hellbenders a better chance, Briggler and MDC fisheries staff John Ackerson and Chuck Wichern created the first hellbender nesting box of its kind.

“We developed some prototypes in 2008 and 2009,” Briggler recalled. “We put a few in the wild and had a few animals using them, but after learning more about the rocks they preferred, we settled on one design. In 2010, our first true test, we installed seven boxes in June 2010 in an Ozark hellbender stream.”

Briggler and his team returned to check if their nesting boxes were in use later that fall.

“I went up to box number six and a male tried to bite me,” laughed Briggler. “But that was a good sign he was likely defending a nest. When we opened the lid of the box, we found well-developed eggs. The sunlight was hitting them, and they shimmered like little golden nuggets.”

Following that successful use, researchers added numerous nest boxes in multiple rivers across Missouri.

Protecting the Ghosts

In addition to the Saint Louis Zoo, MDC has partnered with the U.S. Fish and Wildlife Service, U.S. Forest Service, National Park Service, Arkansas Game and Fish Commission, and other agencies to enhance propagation efforts to ensure hellbenders remain a part of Missouri’s biodiversity.

Most Missourians can’t recreate Ozark streams in their backyard to breed and raise hellbenders, but several things can be done to help Ozark and eastern hellbenders.

If you accidentally catch a hellbender while fishing, cut the line near the head and release it back into the river. The hook will rust away in a few weeks. You should also report the incident by calling your local MDC office or conservation agent. (See Page 3 for contact information.)

Respect Missouri’s waterways, and hellbenders’ homes, by keeping rivers and streams clean. Leave no trace when outdoors or join a local Stream Team to care for and monitor rivers.

Seeing hellbenders in the wild is a rarity because they’re so endangered. It’s unlawful to search for wild hellbenders because it could destroy their habitat.

“My hope is that someday, it will be commonplace for people to see them,” Elden said. “But at this point in time, they’re ghosts to an extent, and that’s the way it should be. Until they’ve completely rebounded, they need privacy, and they need patience.”

However, Elden says the most meaningful hellbender act is to take pride in the individuality this species offers.

“This weird, ugly animal, especially the Ozark subspecies, is yours,” said Elden. “It’s an animal that belongs to our state and to our Ozark plateau and we should be insanely proud of that.” 

MDC Statewide News Services Coordinator Jill Pritchard is the host of MDC’s award-winning podcast, Nature Boost. Scan the QR code to find her 2024 two-part podcast featuring hellbender restoration.