A salt lick is a deposit of mineral salts used by animals to supplement their nutrition, ensuring that they get enough minerals in their diets. A wide assortment of animals, primarily herbivores, use salt licks to get essential nutrients like calcium, magnesium, sodium, and zinc. When a salt lick appears, animals may travel to reach it, so the salt lick becomes a sort of rally point where lots of wildlife can be observed.
Farmers have historically provided salt licks for their cattle, horses, and other herbivores to encourage healthy growth and development. Typically a salt lick in the form of a block is used in these circumstances, and the block may be mounted on a platform so that domesticated animals do not consume dirt from the ground along with the necessary salt. Salt blocks for farm animals can also be treated with medications, which may be convenient when someone needs to medicate shy animals, or a large group of animals.
Some people also use artificial salt licks to attract wildlife such as deer and moose, along with smaller creatures like squirrels. Animals may be attracted purely for the pleasure of the humans who install the salt lick with the goal of watching or photographing animals around the salt lick, and they are also used by hunters to encourage potential prey to frequent an area. Wildlife biologists may use salt licks as well, to assist them in tracking populations, and wildlife salt licks can also be medicated; deer, for example, might be fed birth control to keep them from proliferating in areas where there are few natural predators.
Artificial salt licks for wildlife come in two forms: blocked and bagged. Bagged salt licks are designed to be buried in pits to create a more realistic form of salt lick, with the salts and minerals leaching out in wet weather to form a salt deposit which will attract animals. Block licks can be installed directly on the ground, or mounted on platforms, depending on personal taste.
The universal popularity of salt licks with a wide range of animals illustrates the ways in which wildlife naturally seek out nutrition which is essential to their survival. Salt licks can also provide nutrition for predators, in the form of conveniently-located prey who may be distracted by the salt lick long enough to become a snack.