Evaluation of Conditioned Taste Aversion as a Method to Reduce Predation of Wildlife Eggs by Feral Pig (Sus scrofa)

Abstract

Feral pigs are introduced predators to Australia and New Guinea. Predation by feral pigs on eggs and hatchlings of nationally protected sea turtles and other wildlife can cause significant mortality. Several control techniques are available to minimize pig predation but available techniques are expensive and of limited success. A potential method is to ‘teach’ feral pigs to avoid predating eggs by using Conditioned Taste Aversion (CTA). In this study, it was hypothesized that if eggs were treated with deterrent chemicals, feral pigs would develop an aversion to the eggs, and would stop predating them. Sixteen feral pigs were presented with eggs treated with the distasteful chemicals: TBZ and LiCl for 5 consecutive days following a pre-treatment phase during which they were fed untreated eggs. The percentage of eggs ‘predated’ during the treatment phase was lower than in the pre-treatment phase, though in most cases this difference was not statistically significant. Most eggs predated during the treatment phase were only partly eaten, suggesting that pigs were “taste-testing”. In addition, pigs consumed similar proportion of untreated eggs and control eggs during the pre-treatment and post-treatment phases