Wildlife and Ecosystems

Limestone caves maintain an almost constant year round temperature. (The temperature of the limestone is controlled by the average annual temperature of the area.) Marengo Cave's temperature is about 52.1 degrees. Its humidity is very high---nearly 100% in many areas of the cave.

Detritus

Since total darkness exists beyond the cave entrance, only a few non-green plants can grow in the cave's dark interior. Detritus (organic debris) can be brought into the cave by surface water and flowing cave streams. Detritus consists of sticks, animal wastes, dead animals, leaves, and dead plants. It is the bottom of the food chain inside the cave.

Fungi

Fungi are carried into the cave by air currents, in water, and on the bodies of animals. Fungi obtain their nourishment by breaking down the detritus inside the cave. Fungi (growing on decaying wood) can occasionally be found inside Marengo Cave.

Troglobites, Troglophiles, and Troglozenes

List of Animals by Category

Troglobites

  • isopods
  • millipedes
  • springtails
  • amphipods
  • blind crayfish

Troglophiles

  • salamanders
  • cave crickets
  • spiders
  • flies
  • fungus gnats
  • cave beetles

Troglozenes

  • white footed mice
  • bats

Insects such as beetles and mites feed on molds and bacteria. Cave animals living in water also eat floating bacteria. Beetles, other insects, and small aquatic animals serve as food for the larger predators. Organic matter is returned to the cave environment through the dead bodies and droppings of these larger predators.

Troglobites

Troglobites, cave dwellers, are animals that must complete their life cycles inside a cave.

Troglophiles

Troglophiles, cave lovers, can complete their life cycles inside or outside the cave.

Troglozenes

Troglozenes, cave guests, are animals that cannot complete their life cycles inside a cave.