Salt lick

A mineral lick (also known as a salt lick) is a place where animals can go to lick essential mineral nutrients from a deposit of salts and other minerals. Mineral licks can be naturally occurring (natural licks) or artificial (such as blocks of salt that farmers place in pastures for to lick). Natural licks are common, and they provide the biometals (sodium, calcium, iron, phosphorus, zinc, and trace elements) required in the springtime for bone, muscle and other growth in deer and other wildlife, such as moose, elephants, tapirs, cattle, woodchucks, domestic sheep, fox squirrels, mountain goats and porcupines. Such licks are especially important in ecosystems with poor general availability of nutrients. Harsh weather exposes salty mineral deposits that draw animals from miles away for a taste of needed nutrients. It is thought that certain fauna can detect calcium in salt licks.

Many animals regularly visit mineral licks to consume clay, supplementing their diet with nutrients and minerals. Some animals require the minerals at these sites not for nutrition, but to ward off the effects of secondary compounds that are included in the arsenal of plant defences against herbivory. The mineral contents of these sites usually contain calcium (Ca), magnesium (Mg), sulfur (S) phosphorus (P), potassium (K), and sodium (Na). Mineral lick sites play a critical role in the ecology and diversity of organisms that visit these sites, but little is still understood about the dietary benefits. "The adjectives ‘mineral’ and ‘salt’ bear witness to the common proposition, in the ecological literature, that animals eat soil to satisfy a craving for nutrient minerals, resulting from inadequate forage. However, for wild animals that frequent licks, sodium is the only mineral identified so far, with strong evidence that an extra supply is indeed needed and sought in some cases."

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