Artificial reintroduction of wild animals: how frequently does it happen, and what is the purpose?

Question

One of the most debated issues concerning wilderness, in Italy, is the reintroduction (or bizarrely large increase in the population) of animals almost extinguished till recently.

While in most cases the artificial reintroduction of wild animals seems to be a metropolitan legend that finds easy spread because of ancestral fears, as it is the case of wolves and bears (the first ones reappeared because of the protection enjoyed by central authorities, while the latter ones reappeared because of both migration from alpines countries and protection as well), there are a few real and well-documented cases, such as the strong increase in the population of boars, that is apparently caused by the hunters' national agency that yearly releases boars that should then be hunted down for sports.

I would like to have a sense from you people of how frequently wild animals' populations increase artificially, and what the usual causes are (I expect that often the cause is the species protection, but--as in the case of Italian boars--this is not always the case).

Answer 1

It happens fairly often, and usually the purpose is to reintroduce the animals to places where they used to be but were wiped out. This is know as species reintroduction/restablishment.

Species reintroduction is the deliberate release of a species into the wild, from captivity or other areas where the organism is capable of survival. The goal of species reintroduction is to establish a healthy, genetically diverse, self-sustaining population to an area where it has been extirpated, or to augment an existing population. Species that may be eligible for reintroduction are typically threatened or endangered in the wild. However, reintroduction of a species can also be for pest control. For example, wolves being reintroduced to a wild area to curb an overpopulation of elk or deer. Because reintroduction may involve returning native species to localities where they had been extirpated, some prefer the term "reestablishment".

Species reintroduction

Wikipedia has a long list of the animals that have had this done, and there are organizations like Rocky Mountain Elk Foundation or government agencies that have initiatives set up to do this.