Scott House has been in plenty of tight spots. He wouldn't have it any other way.

The Cape Girardeau man feels right at home in the muddy, damp underground world of Missouri's caves where the average yearly temperature is about 55 to 58 degrees Fahrenheit.

House is one of about a dozen Missourians who volunteer their time to find, explore and map caves in the state.

Missouri has over 6,000 known caves, second in the nation to Tennessee, which has some 8,000 caves.

Missouri's numerical distinction comes largely because of House and other cavers -- members of the Missouri Speleological Survey -- who spend much of their time looking for caves and drawing detailed maps of their rock formations and underground passageways.

The association was founded in 1956. At that time, known caves numbered only 437. All the rest have been found and documented in the last half-century, House said.

Today, there are 6,037 documented caves spread across 83 counties in Missouri, most of them on private land. Public agencies own about 1,500 caves in the state.

Perry County in Southeast Missouri has the most known caves of any county with 656. In contrast, Cape Girardeau County has 41 caves, Bollinger County has four caves and Scott County has three caves.

There are few caves in the Bootheel, with its flat terrain stretching from southern Scott County all the way to the Arkansas line.

More caves are being found each year.

"We are finding over 100 caves a year right now," he said. Most of those are being discovered in south-central and southwest Missouri.

Members of the Missouri Speleological Survey, or MSS, held their spring meeting in Rolla on Saturday. The meeting typically draws about 30 to 40 cavers. The group has about 150 members.

Today, House and others in the group plan to go caving.

House, a 51-year-old retired elementary school teacher, works with the Cave Research Foundation but acknowledges that it's less a job and more of a volunteer effort.

The work of the MSS has resulted in detailed maps and information about caves, documents that are stored in numerous file cabinets at the Missouri Department of Natural Resources office in Rolla.

House maintains computer records of Missouri's caves for MSS on his home computer.

The volunteer efforts of the MSS have given Missouri the most complete cave records of any state, House said.

In contrast, Kentucky just recently started compiling a survey of its caves.

Caving is an endeavor that attracts a wide variety of people, many of whom simply like to explore caves.

The small group of cavers who do most of the mapping of caves include a freight train conductor, an armory technician at Fort Leonard Wood and the house chef for a fraternity at the University of Missouri.

"You never hurt for an interesting conversation when you are caving," House said.

He and Ben Miller, who works at Onondaga Cave State Park near Cuba, Mo., discovered a cave in Shannon County near the Current River in April. The cave was about 200 feet long.

"We called it Six-Mille Cave," House said, explaining that 'mille" is the Latin word for thousand. The cavers named it to recognize the fact that Missouri now has some 6,000 caves.

The cave was one of 55 new caves recorded since the beginning of the year, House said.

Most new caves are discovered in winter when entrances can be more readily seen among the underbrush. Cavers also prefer winter explorations because they don't have to deal with ticks or poison ivy, House said.

Some entrances are barely large enough to crawl into. "You ought to stay out of caves if you are afraid of tight places," House said.

Like all serious cavers, House goes into caves with the right equipment including a safety helmet outfitted with a headlamp.

While there are large caves in the state -- the longest is Crevice Cave in Perry County, which extends more than 28 miles -- the average cave is less than 400 feet long, Miller said.

Miller, 26, has been exploring caves since he was 8 years old. Now he spends most of his working days giving tours of Onondaga Cave. But in his spare time, he searches for new caves to explore and map.

"We find quite a few caves just by talking to landowners and also just going out and walking the land," he said.

Like other dedicated cavers, Miller and House won't give out specific locations of caves. Landowners don't want people trespassing on their property, House said.

Caves are precious resources, Miller said. Dedicated cavers don't want people trashing or otherwise damaging caves.

Cavers like House subscribe to the popular conservation slogan: Take nothing but pictures, leave nothing but footprints, kill nothing but time.

But caves are more than a hobby or interesting footnotes to Missouri's landscape. Caves offer natural drainage, carrying water underground.

There are other environmental issues too. Trash in the past often was dumped in sinkholes and rain washed the trash into connecting caves, Miller said.

Bats and blind cavefish thrive in the darkness of caves. The Tumbling Creek cavesnail is found only in one Missouri cave, located in Taney County, and has been on the endangered species list since 2002.

Prehistoric Indians used caves for shelter and burial, and as a source for water, clay, flint and minerals.

By the 1840s, German immigrants were using caves to store beer.

There's a popular misconception that caves were routinely used as hideouts by outlaws, House said. "Robbers didn't hang out in caves as people thought. The trouble with hiding out in a cave is that there is one way in and one way out," he said.

But caves were used for dances and meeting rooms, House said.

In the 1880s, Mark Twain popularized Missouri caves in his fiction and caves became tourist attractions.

Missouri has about 25 show caves that cater to tourists. They include the state's deepest cave -- Marvel Cave -- at the Silver Dollar City amusement park in southwest Missouri. The cave is 383 feet deep.

But cavers like House and Miller aren't picky when it comes to caves. To them, even the smallest opening in Missouri's underground is worth the trip.

mbliss@semissourian.com

335-6611, extension 123