Introduced invasive pigs, although (success!) these animals no longer occur on the island. Kiwis were there while I was there, trying to eradicate them. They were successful just six months later. The last feral pig was destroyed on July 5, 2006, and the native flora is reportedly on the rebound. Here's a fun sounding article: Rapid eradication of feral pigs (Sus scrofa) from Santa Cruz Island, California ""In 411 days, a total of 5036 pigs were removed....Sterilized adult pigs fitted with radio collars were subsequently used to aid in the location of surviving wild pigs and to monitor the success of the project. Female telemetered pigs were more effective than males at locating remaining wild pigs. Only 10% of the last 102 pigs (the last 20 or so present in each fenced zone) were dispatched as a result of being found with a telemetered pig, but telemetered animals were responsible for finding 43% of the very last pigs once normal hunting had ceased."" Fishing with female pig.