Subterranean Conservation

Caves and groundwater systems are crucial for the conservation of biodiversity. They provide habitat to some of the world's rarest and most endangered animals yet are not well protected by the existing network of nature preserves. Despite the ecological importance of subterranean habitats, they have not been thoroughly studied and little is known about their ecosystems.

Cave Critters
Cave animals are mysterious and in some cases have bizarre appearances and unique traits. Their habitats are difficult and dangerous for people to explore.

See examples and profiles of animals that live in this shadowy realm.

Why is Subterranean Biodiversity Important
The caves of the world may be found in many places, such as glaciers and lava fields, but the major cave-bearing landscape is karst, a term for lands whose bedrock has been hollowed out over the ages from the slow enlargement of cracks by acidic rainwater. Karst landscapes are found on every continent, and the groundwater they contain are the world's most important water reserves.

• Karst habitats comprise 20% of the Earth's land surface.
• One-quarter of the world gets its freshwater from karst aquifers.
• Scientists estimate 60,000 species of cave-dwelling animals worldwide, with 10% in North America.
• An estimated 90% of subterranean life has not yet been described.
• Animals found only in caves and groundwater habitat represent more than half of the imperiled species in the United States, but less than 4% have federal protection.
• Caves harbor a rich diversity of freshwater fishes, amphipods, and crayfishes, which are among the world's most endangered animals.
• Cave animals live much longer than their surface counterparts-sometimes 10 times longer.

Dr. G.O. Graening of The Nature Conservancy snorkels to survey for cavefish. © David Taylor

Learn where the Conservancy is working to address the conservation needs in subterranean environments.

In the News
Tenn. Caves Offer Troves of Undiscovered Treasures
Washington Post
November 1, 2004

Caver and speleothems formed by water depositing calcite over thousands of years. © Dave Bunnell

Threats
Habitat alterations, such as increases in sediment and nutrient loads, can cause great harm to cave species. Because resources are sparse in the cave environment, many cave-dwelling species grow exceptionally slow and have very low reproductive rates, making them especially vulnerable.

Some examples of subterranean species under threat:

• At least 10 subterranean species in the U.S. have gone extinct due to human influence.
• The cavefish of Madagascar are threatened due to mining and illegal collection for the aquarium trade.
• Illegal or excessive collection of rare fishes for the aquarium trade has brought at least 5 cavefish species to the brink of extinction.
• The mining of bat guano for fertilizers in caves of Jamaica and Central America destroys habitat for rare insects that live in the guano.

What the Conservancy is Doing
Cave science and conservation are relatively new concepts, but many places that the Conservancy owns or manages protect rare cave and groundwater animals. The Nature Conservancy formed a Subterranean Biodiversity Workgroup in the late 1990s, which has grown to encompass over 50 Conservancy programs worldwide and several hundred staff and partners. This network will begin holding annual conferences, and expanding information and links on the Internet. Databases are being created to compile the known distribution and status of the world's subterranean animals (and a few plants), as well as links to institutions and taxonomists that can help generate more data. With enough data, this network can rank sites around the world in biological importance and degree of threat, and create conservation plans to protect these places. But increased human and financial resources are needed to accomplish this goal.

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