paul_burger@nps.gov
Hydrologist, Carlsbad Caverns National Park, New Mexico


Back to Chapter 3: Parks as Laboratories

Mapping the floor of America’s deepest lake with sonar
By William M. Brock

What does NASA have to do with the National Park Service?
By Anita Davis

National Cave and Karst Research Institute begins organizational phase

New moth and butterfly species identified in the Smokies

Award-Winner Profile - Dr. Howard Ginsberg honored

“New” waterfalls discovered in Yellowstone

Satellite imagery used for long-term park monitoring

First Canon National Parks Science Scholars retreat

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The discovery of a small rock—Martian meteorite ALH84001—on an Antarctic ice field in 1984 and the discovery of possible Martian fossil bacteria on the rock in 1994 sparked a search for life in extreme environments where organisms subsist with few organic nutrients. Such extreme environments include caves, and caves are preserved in many units of the national park system.

In 2000, scientists from the University of New Mexico continued their six-year search for life in caves of Carlsbad Caverns National Park, New Mexico. They braved pits that are more than 200 feet (60 meters) deep and mazes of tight, dirty crawls. With the help of cave specialists of the National Park Service, the scientists discovered previously unknown bacteria on the walls and in the pools of several caves.

Some bacteria are hidden in mats of red, black, and orange corrosion residues on the cave walls where they obtain energy from tiny amounts of iron and manganese in the limestone bedrock. These bacteria may be analogs for life beneath the stony, barren surface of Mars where satellite imagery and samples revealed large amounts of iron in rock.

In Lechuguilla Cave, only 1 mile (1.6 kilometers) from the world-famous Carlsbad Cavern, pools are also teeming with life. According to Dr. Larry Mallory, a microbiologist with Biomes, Inc., “There is more biodiversity in some of the pools of Lechuguilla than in the Amazon jungle.” By releasing enzymes that kill competitors, the bacteria in these pools compete fiercely with each other for the few available nutrients. Testing in the laboratory revealed that some of these enzymes attack leukemia cells and may someday become instrumental in cures of human diseases.

Unfortunately, foreign bacteria shedded from human skin, hair, and clothes harm the native microbes by outcompeting them for food. Additionally, food particles, flakes of dead skin, hair lint, and dirt left behind by people can overwhelm portions of the cave’s nutrient-poor ecosystem, altering it in favor of exotic surface microbes. Only a few contacts with cave explorers have already decimated native microbe populations in some of the pools of Lechuguilla Cave. Explorers and scientists, who often camp in the cave for several days, are now required to eat and sleep on drop cloths that catch food, skin, and hair. Furthermore the explorers are restricted from approaching pools they discover and are required to report their discoveries to the Cave Resources Office of the park and to the investigators of the University of New Mexico. Scientists approach the pools in Tyvek clean suits and set up clean glass slides that remain in the cave for as many as five years. After the slides are collected, scientists culture the bacteria in a laboratory and attempt to isolate important enzymes to gain an understanding of life in extreme environments.

Continuing research will further an understanding of the complex ecosystems and life-forms in the caves of Carlsbad Caverns National Park. Already the studies reveal the delicacy of these organisms and the importance of appropriate management of the caves.

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Last Updated: 06/17/2001
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