Photo: USFWS

Thomas Floyd didn't go into the stream that day planning to crash a snot otter sex fest.

The biologist and his team from the Georgia Department of Natural Resources usually try not to bother the animals—commonly known as hellbenders—during mating season. Floyd had actually been belly-crawling over the streambed and peeking under rocks to count larvae, but instead of finding little, wiggly proto-salamanders, he stumbled onto an ancient ritual of hellbender lovemaking.

A two-foot-long dominant male, called a den master (prrrr…), had selected a rock and was guarding it against other hellbenders. Like a bouncer at an exclusive club, the den master ensures that only the fittest giant salamanders can gain access to the champagne room—in this case, a crevice in the bedrock.

“We just happened to stumble across it,” says Floyd. “If we had been there 25 minutes earlier or later, we would have totally missed it.”

Footage like this is exceedingly rare (and is, in fact, safe for work).

Hellbenders are secretive creatures that spend their entire lives skulking beneath rocks and shimmying through substrate. So even though these massive salamanders inhabit rivers and streams all over the eastern United States, from Missouri to Georgia on up through New York, few people ever see them. Another reason for the low profile is because populations have been declining for at least half a century.

“Overall, in the majority of the habitat, the historical distribution of hellbenders is in dire, dire straits,” says Floyd. “There are areas where they haven’t been seen in years.”

With fewer than 600 likely remaining in the wild, the Ozark hellbender was declared endangered in 2011, and the U.S. Fish and Wildlife Service is currently reviewing the protective status of its cousin, the eastern hellbender.

Like many amphibians, hellbenders are ecological indicators—meaning where there are healthy hellbenders, there are healthy environs. So it’s no surprise that their downfall is mostly tied to poor water quality. Even low sedimentation levels created by development, deforestation, and agriculture can kick up enough sand to fill in those underwater rock crevices that hellbenders depend on for their orgies—and the consequences of their orgies: baby hellbenders.

Sedimentation might also compromise the animals’ ability to get oxygen. Floyd is currently conducting a study on this, but the thinking goes that the clearer the water, the more easily hellbenders can breathe through their skin (a feat all amphibians can do but which hellbenders take to the extreme). All that extra silt floating around might also inhibit the development of their young, which hatch with funky external gills that look like branch coral.

Pollution in runoff, such as endocrine-disrupting chemicals, heavy metals, and pesticides, might also interfere with reproduction, and when waterways are stocked with nonnative game fish, young hellbenders are often on the menu. The list of woes goes on…chytrid fungus, a notorious amphibians killer across the globe, has also proven lethal to hellbenders.

Japan’s pet trade has also scooped up many a North American snot otter. (Note: Hellbenders make pretty slimy and hard-to-care-for life companions. Just say no.)

In years past, unscrupulous individuals caught enough of these animals to devastate ecosystems. Fishermen, erroneously believing hellbenders are poisonous and destructive to game fish populations, have also been known to kill them. For these reasons, when you look at government documents, you’ll see that the hellbenders’ location data has been blacked out to protect them, like a classified military communiqué.

“If you know anything about hellbenders and how to find them, you can do a lot of damage in a short amount of time,” says Jeff Ettling, the project manager for the Ron Goellner Center for Hellbender Conservation at the Saint Louis Zoo.

Photo: Mark Wanner/Saint Louis Zoo Captive-bred hellbenders developing inside eggs at the Saint Louis Zoo.

Like Floyd, Ettling has seen his share of snot otter boogie. In 2011, he and his colleagues became the first in the world to successfully breed hellbenders in captivity. They had to fine-tune everything from the containment and filtration materials to the water ion content. It took more than a decade for the team to get it right. (Apparently you need more than Bob Seger’s “Night Moves” to get hellbenders in the mood.)

Today, Ettling has around 4,000 of the salamanders under his care. This Ozark hellbender hatchery includes 97 breeding aquariums, three artificial streams, and five zookeepers who work with hellbenders and hellbenders only to prevent chytrid contamination from other types of amphibians or reptiles.

Best of all, the zoo-bred ‘benders have been able to augment Missouri’s wild populations.

“I think we’re all much more optimistic about their future,” he says. “We can turn things around, and the young ones seem to do well out in the wild, even with this onslaught of environmental degradation going on.”

But even though scientists have uncovered some of the mysteries surrounding salamander sex, others questions remain. Both Floyd and Ettling are concerned that populations in the wild often consist of only young larvae or elderly breeders. The middle-aged seem to be missing, and nobody can say for sure why.

Hellbenders can reach age 30 or older, and it takes about five years before larvae reach sexual maturity. This delay can make it difficult for scientists to evaluate how the animals are faring in a certain area. “You can have a dying population, and it takes a long time before you know it,” says Floyd.

Most of us will never see a hellbender in person, but we need to realize just how connected the land and water worlds are. The simple acts of cutting down trees or allowing cattle to cross a stream can kick up enough silt to put the kibosh on hellbender sexy times for miles—a mood-killer that rings out across the decades.

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