Pigs in modern forests

The damage caused by pigs is probably incalculable. Professor Kirk, in 1896, claimed that the pig was responsible for the eradication, in mainland New Zealand, of the tuatara. He also claimed that it nearly wiped out the native orchid Gastrodia, and Cockayne blamed it for the near-extermination of the Chatham Island lily. Pigs are also very fond of bracken fern. While this plant is obviously holding its own, their attentions delay regeneration of soil-eroded slopes. On the credit side, however, it has been suggested that the pig, through rooting of burrows, helped to keep down rabbit numbers.

The damage nowadays that is the most obvious is in the exotic forest plantations. Large numbers of pigs are destroyed every year by officers of the New Zealand Forest Service. The pigs have been known to systematically demolish acres of young trees, uprooting them and grubbing around in the soil. Many farmers swear that large sows and boars kill young jambs and eat them; it is interesting to note that the pigs that do this are suffering from a calcium deficiency—in fact, in the Kaingaroa forest pigs can be caught in traps baited with bones.

Wild pigs so far have very little economic value, providing little more than energetic and rather dangerous sport. However, with wild pork appearing on the menus of various enterprising restaurants, and considering the sudden profitability of the antlers and meat of deer, one never knows what the future of this exotic intruder holds in store.