Pine Creek is quiet. Shallow water rushes over slippery rocks, gurgling through Pennsylvania's famous forests on its way to the Susquehanna River. Nobody is fishing. Nobody is camping. Just 40 miles from Pennsylvania's Grand Canyon, this leafy spot appears to be nothing more than a picnic table and a pretty view.

Peter Petokas knows better. Armed with a wet suit, snorkel gear, a wooden block, a lumberjack's peavey and two eager interns, the Lycoming College biologist dived into the 2-foot deep creek and cranked up a boulder.

"Got one!" he yelled.

Wriggling out of his gloved hands was a creature most people will never see in the wild: the Eastern hellbender.

With a flat head, a supple, lizard-like body and webbed feet, the hellbender is the largest salamander in North America. Nearly gone from every place in the country that it once called home, it still lives in this remote tributary of the Susquehanna River.

Hellbenders will only live where the water is pristine and where streams flow freely. To thrive, they need large rocks to hide under, abundant forest cover and water that is not too warm. They aren't great swimmers, and are picky eaters, favoring crayfish—and then, only the native kinds.

Hellbenders are not the sort of animals likely to share a wildlife poster with the spotted owl or the polar bear. Slimy and fleshy, with a reputation (not entirely undeserved) for biting, they are sometimes called the Allegheny alligator, devil dog or snot otter. They breathe through the folds of their skin and do not leave the water.

Their decline has not prompted major restoration efforts, in contrast to the huge investments and research into reversing the dropping numbers of shad or oysters. Hellbender research papers are hard to come by, and hellbender conferences infrequent. Some states, including New York, Maryland and Missouri, are trying to determine why they've lost the hellbenders and how to bring them back. But, Patokas said, there's no concerted effort to share information, breed the animals or rebuild habitat.

"Nobody's watching. Nobody's noticing," he lamented. "The scary part is, we don't know why they died out in certain areas in the first place."

And yet, the hellbender is coming out from under its rock to try to tell us something. Where it exists, it tells a story of clean water, stream banks that aren't delivering a lot of sediment and a temperature that's managing to stay in check despite extreme heat. Where it once lived and doesn't anymore, it's telling biologists that something's amiss.

After handling more than 1,400 hellbenders over the last seven years, Patokas has some clues for decoding the elusive salamander's message. Invasive crayfish — particularly the rusty crayfish — have outcompeted the natives for food and habitat, leaving the hellbenders to starve. Habitat also plays a role. If an area becomes developed and loses its forest cover, it will likely lose its hellbenders. Dams also impede their movements. And while Chesapeake Bay wildlife officials have made accommodations to shepherd shad, herring and eels past dams, there are no such efforts to help the hellbenders.

That could change though, as a 2010 federal restoration strategy for the Chesapeake Bay and its watershed identified the hellbender as a "critical living resource" because of its role as an indicator of healthy stream habitat.

Petokas is also testing whether higher levels of mercury in the atmosphere are entering crayfish and harming the hellbenders.

Petokas said that he believes that historically, acid mine drainage killed many of the hellbenders. Now, there is also the looming threat of natural gas drilling. The hellbender habitat overlays with the Marcellus Shale, and drilling for natural gas began in the watershed about five years ago. Spills of hydrofacking fluid have killed fish in several streams, but Petokas doesn't know how much they've affected the hellbenders.

Formally known as the Cryptobranchus alleganiensis, the hellbender got its name from early settlers, who decided the salamander "looked like a creature from hell, where it must be bent on returning," according to the Missouri herpetologist Jeff Briggler. American Indians reportedly ate them, but nobody would now — in several states, they're protected, and they reportedly taste terrible.

Hellbenders enjoy relatively long lives — about 30 years — and can grow up to 29 inches. But they're not prolific breeders. Their need for clean, pristine waters can lead to both a slow decline over time or an immediate annihilation.

In 2006, a Norfolk Southern train derailed and spilled sodium chloride in Sinnemahoning Creek, killing thousands of trout and smallmouth bass as well as at least 36 hellbenders. The Pennsylvania Fish and Boat Commission estimated it would take several years for those populations to recover. But the hellbender never did. To this day, Petokas says, there are no hellbenders in the Sinnemahoning Creek.

Hellbenders once lived throughout the Susquehanna's watershed in Maryland, and may have lived elsewhere, but their populations were not recorded. Now, they are only found in the Youghiogheny and Casselman rivers in the far western corner of the state. Neither of those rivers is in the Chesapeake watershed.

Jonathan McKnight, associate director of the Department of Natural Resources' Wildlife and Heritage Service, said the state has considered breeding hellbenders and putting them into rivers where they historically lived, particularly because Maryland stream surveys in the two rivers where hellbenders remain are not finding many young animals. But funding for such a program is uncertain, and so is the survival of the fledglings.

"We're not really sure what the causes of the decline are. We can't point to one thing, so we're reluctant to raise them in captivity," McKnight said. "We're so concerned about this animal that we don't want to do the wrong thing."

The salamanders are making a comeback of sorts at local zoos. The Maryland Zoo in Baltimore has an exhibit on them, as do the Knoxville and St. Louis zoos. At Lycoming, students can watch Wanda, Creamsicle and Melvin hiding under rocks in their tanks in Patokas' lab.

Occasionally, a boater or angler will call Petokas to report a sighting. But it's rare. The hellbender stays under its rock and only comes out at night to hunt for food; even then, it doesn't go far.

A New York City native, Patokas had never heard of hellbenders when he began his graduate research at the State University of New York in Binghamton. In the early years, he said, he didn't know what he was doing in terms of research. He looked for them but never found any. When he joined the Lycoming faculty in 2003, a colleague invited him scuba diving, with the promise he'd see hellbenders in the wild.

He did, and Patokas has been hooked on the salamander ever since. Grants from the Pennsylvania Fish and Boat commission as well as private foundations enable him to continue the labor-intensive work, which requires teams of at least three and hundreds of hours in the field.

Part of what keeps Patokas going is the underdog story — the unloved and unheeded canary in the proverbial mine shaft, with a face only its own mother could love. But part of it is the challenge of hunting something few other people would.

After Petokas lifted the rock, his interns, Michelle Herman and Chelsea Taylor, helped him bag the skittery salamanders, iced them down, and put down a fishing bobber to mark the rock they came from. Then, the team carried the hellbenders to a picnic table where they tagged them, weighed them, measured them and felt their stomachs to determine their last meal. Merman and Taylor also swabbed their insides, looking for a fungus that has been killing amphibians since the 1990s.

Patokas also checked their bodies for scars, missing toes and other signs of underwater skirmishes. The animals don't like to share their rocks, and will fight for them.

The team also tested the water to determine its oxygen levels, clarity and chemistry. Every other year, they visit about 20 sites and handle hundreds of hellbenders.

At Pine Creek, the team caught nine hellbenders in an hour. Four were "recaptures," having been tagged in 2006 and 2007. Petokas was elated; the real excitement in this work, he said, is not finding new populations, but in rediscovering old ones so the team can see how much they've grown. Also exciting: finding a juvenile, as they did one week in July, and finding 10 under one rock, which is the record for habitat-sharing.

As dump trucks rumbled on the rural road above his makeshift hellbender lab, Petokas pondered a future for the salamander that may be even more perilous than the past. Drilling has slowed down here, in part because of the dip in natural gas prices, but drilling for natural gas in these hills is likely to continue for many years.

To know how the drilling will affect the hellbenders, Petokas said, the state must know what the population looks like now.

"If there was a spill in Pine Creek, it would wipe out half the hellbenders in the Susquehanna basin," he said. "We're doing this partly to make sure they're being monitored over time. If anything happens, we're there."