Cave / Karst Systems

Cave formations in Hurricane Crawl

Photo courtesy of Dave Bunnell

 

What is Karst?

Karst is a landscape underlain by soluble rocks like limestone or dolomite, where the topography is formed by the dissolving of rock and may be characterized by sinkholes, sinking streams, closed depressions, underground drainage, and caves.

 

By some accounts Sequoia and Kings Canyon National Parks could have been set aside solely to protect the amazing caves found in this area of the Southern Sierra Nevada. The two parks protect half of the caves more than a mile long in California, the longest cave in the state, numerous karst streams, and some of the best alpine karst topography in the United States. The caves contain Pleistocene era fossils, rare minerals, and unique animals. They are the sites of numerous scientific research projects and provide recreational opportunities to thousands of park visitors each year.

These parks contain at least 275 caves. This number continues to rise as more caves are discovered. Caves are found primarily in the western one-third of the parks in narrow bands of marble. Caves form where streams on the surface are diverted underground, and the mildly acidic waters can dissolve soluble rocks like limestone, eventually forming caverns.

Park caves occur at a variety of elevations, from 1,640 feet to more than 9,800 feet. As a result, cave temperatures range from just above freezing to over 60ᵒF. Cave conditions vary across this elevation range. The parks' lowest cave is amidst oaks and grasses, and its passages are warm, dry, and dusty. In contrast, some alpine caves have floors or walls of transparent ice.

 

Azurite blue formations in Lilburn Cave

Photo courtesy of Bill Frantz

Cave Features

Cave formations (called “speleothems”) include long curtains, tall stalagmites, deep rimstone pools, masses of angular or curving growth forms called “helictites”, and 10-foot diameter shields. Park caves also display a diverse assemblage of colorful minerals. They form blue, green, yellow, black, white, orange, and red deposits and formations along walls, ceilings, and floors of caves. The parks’ caves include rooms 100 feet in diameter and tiny passages barely big enough for a small person to squeeze through. Some caves have active stream systems, while others are dry and abandoned remnants of ancient water-flow patterns.

 

The Crystal Cave millipede on roots in the Rapunzels Canyon of Crystal Cave. This millipede is a species new to science and was named for John Muir (Amplaria muiri).

NPS Photo - Joel Despain

Cave Life

Park caves host a diversity of animals. Scientists have discovered at least 40 new invertebrate species since 1965. Cave invertebrates are remarkable in that many are endemic only to the parks. In some cases, they may occur only in one watershed, or even in an individual cave. In Clough Cave, three endemic invertebrates occur, and a total of 58 different species of animals are documented. These include spiders, a harvestman, scorpions, pseudoscorpions, centipedes, beetles, millipedes, flies, a mite, and many more types of invertebrates. Many of the invertebrates found in park caves are not only newly documented for the parks, but also new to science. Vertebrates also use park caves for roosting, shelter, and occasionally food sources; in Clough Cave, four bat species, a raccoon, a rodent, and a snake were documented.

 

Threats

Park cave formations can be damaged by human use of caves. See the Managing Caves page to learn more about how these parks manage caves to protect their fragile features and unique animals and restore caves that have been damaged. Animals that live in park caves can be affected by stressors that affect other park animals: climate change, air pollution, altered fire regimes, and land-use change. Some bat species in the eastern United States are in decline from a disease called White-nose Syndrome. Visit the National Park Service White-nose Syndrome page to learn more about this disease, and see the Crystal Cave page for information on reducing risk of this disease spreading to local caves, especially if you plan on taking a tour of this cave.