All Creatures Great & Small & Underground

From the Washington Post

washingtonpost.com
Tenn. Caves Offer Trove of Undiscovered Creatures
Up to 1,000 Species Await Explorers, Experts Estimate
By Juliet Eilperin
Washington Post Staff Writer
Monday, November 1, 2004; Page A12


DUNLAP, Tenn. -- With his ample midriff, mud-spattered jeans and wire-rim glasses, Julian Lewis does not fit the typical profile of the intrepid explorer. But as he gazed at the craggy cave entrance surrounded by oak and hickory trees, he likened himself to "Star Trek's" swashbuckling Capt. James T. Kirk.

"This is a little bit like Captain Kirk going where nobody's ever been before, from a biological standpoint," said Lewis, an Indiana-based cave expert. "I'm going to unknown biological turf, and I love that, I live for that."

Lewis is in the vanguard of conservationists' ambitious new effort to inventory the living contents of some of the thousands of caves that dominate Tennessee's subterranean landscape. With more than 8,600 known caves, Tennessee has more than any other state, and they provide a home for countless ancient and rare creatures that dwell underground and out of sight.

The caves "are remarkably biodiverse," said David Withers, the state's zoologist. "Very few people know about it. It's not sexy; it doesn't make the papers."

Tennessee's caverns are part of the nation's most elaborate cave network, which extends under Alabama, Georgia and Kentucky, and beyond into Indiana, Virginia and West Virginia.

Most of these caves have never been surveyed for their biodiversity, and some scientific experts estimate that as many as 1,000 species are yet to be discovered. Sheltered until recently from the outside world and with few opportunities to escape, a variety of largely unknown species of cave flora and fauna have evolved out of sight over millions of years.

Many are rarer than ones on the federal government's endangered species list. Biologists use a "Global Rank of Rarity Scale" that specifies whether a species exists in one to five sites in the world, six to 20 sites, 21 to 100 sites and so on. After exploring 22 caves near the Tennessee-Kentucky border last year alone, Lewis discovered 43 species of global significance, including the cave flatworm, the two-clawed spider and four previously unknown species of millipedes.

Withers said Lewis, a private consultant who has devoted more than three decades to cave biology, "can go into any cave and find an organism new to science. . . . It blows me away."

Today, many of these sites are under siege, as the toll of development, logging, sewage disposal and vandalism extends into the underground world. Sedimentation left behind by runoff from deforestation and construction, for example, can clog passageways and streams on which animals such as the threatened Tennessee cave salamander depend.

"Big changes to a cave can wipe {grv}out everything," said Heather Garland, the Nature Conservancy's Tennessee program manager for caves and karst, the term for weathered limestone terrain. "Things grow very slowly, they reproduce very slowly. They survive on stability. They're not very adaptable."

Concerned about development's impact on Tennessee's caves, the Conservancy, a private conservation group, launched the survey that Lewis heads, funded in part by the U.S. Fish and Wildlife Service and other private foundations.

Lewis's year-long study of 50 to 100 caves seeks to determine exactly how many cave beetles, crickets, millipedes and other invertebrates thrive there. Conservancy officials say the expedition will be one of the most comprehensive bio-inventories ever conducted in southeastern caves. In the 1950s and 1960s, Thomas C. Barr Jr. surveyed several hundred Tennessee caves and distributed the samples to taxonomists across the country.

Armed with glass specimen jars filled with isopropyl alcohol as a preservative and processed limburger cheese or spoiled yogurt for bait, Lewis and Conservancy staffers have been burying traps in caves dotted across a stretch of eastern and middle Tennessee.

The surveyors must contend with an array of logistical and physical challenges. Most caves are on private land, and landowners are wary of drawing attention to them because they attract vandals as well as drug addicts looking for a place to get high.

Caving is also physically grueling. During a typical trip to two caves, Lewis and his assistant had to scramble through a narrow passage while gripping rocks jutting out from each side, wade on hands and knees through freezing water and slog through "boot sticking" mud.

"My definition of a good cave trip is when you can stop the bleeding at the end of the day," Lewis said cheerily as he prepared to enter. Walking into the dark, the biologist started whistling "We're Off to See the Wizard," pausing to exclaim, "Get ready for the lions and tigers and bears!"

Shining his small head lamp on the traps that had lured small animals over two weeks, Lewis began inventorying the cave's inhabitants. His first haul included a spider, a primitive insect-like creature called a springtail that can catapult itself into the air to avoid predators, and an unpigmented millipede, which he examined while scanning the walls for live specimens.

One trap offered up a rare find, a tiny blind cave beetle called pseudanophthalmus. The water held another trove of creatures, including a blind white crayfish that was probably several decades old and a sand-colored sculpin fish with black spots that seemed to disappear into the muddy waters.

Some of the species of beetles were so small they looked like dots. Lewis said he would be able to distinguish them only under a microscope. "You have to think small when you do this," he said.

Once Lewis issues his final report next year, Garland said, the Conservancy will decide which caves might be worth buying to shield them from development. In the mid-1980s, the Conservancy paid $29,000 to buy Hubbard's Cave and the 50-acre forest that buffers it in McMinnville, Tenn., home to more than 100,000 federally endangered gray bats.

"It's important to identify the caves that support a rare species before something happens to them," said Robert Currie, an Asheville, N.C.-based U.S. Fish and Wildlife biologist. "Knowing where something is is a first requirement before you can protect it."

While state officials could take some steps to guard the caves, their task is complicated by the fact that invertebrates such as the millipedes are not considered wildlife under state law and do not enjoy as many protections.

Some Tennessee animals such as the Indiana bat are on the brink of extinction, but Garland said she is optimistic that conservation advocates would be able to protect many plants and species.

"We still have so much in this state," she said. "We haven't lost everything yet."



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