Burrow

A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion.

Burrows provide a form of shelter against predation and exposure to the elements, and can be found in nearly every biome and among various biological interactions.

Mammal species such as Insectivora like the mole, and rodents like the gopher, great gerbil and groundhog are often found to form burrows.

Some species, such as the groundhog, can construct burrows that occupy a full cubic metre, displacing about 300 kilograms (660 lb) of dirt.

[11] The largest burrowing animal is probably the polar bear when it makes its maternity den in snow or earth.

The Magellanic penguin is an example, constructing burrows along coastal Patagonian regions of Chile and Argentina.

[15] The establishment of an invertebrate burrow often involves the soaking of surrounding sediment in mucus to prevent collapse and to seal off water flow.

Burrowing animals can be divided into three categories: primary excavators, secondary modifiers and simple occupants.

[17] The third category, simple occupants, neither build nor modify the burrow but simply live inside or use it for their own purpose.

[17] Some species may spend the majority of their days inside a burrow, indicating it must have good conditions and provide some benefit to the animal.