Thus, an extract from Gastrolobium peas native to Australia has become the foxes' downfall. Australian wildlife, on the other hand, have become immune to the native plant's poison during the course of evolution. Chunks of meat marinated in the poison have proven a very effective weapon against the foxy plague and are now used throughout the country. In Western Australia, CALM alone drops approximately 700,000 pieces of bait each year. The long-range plan is to eliminate foxes from 3.5 million hectares of land using this method.
Wild cats are more of a headache for the researchers.
Unlike the foxes, they prefer live prey, which makes them tough to bait. New approaches in biological warfare are to further accelerate the crusade against foxes and cats. In Canberra, researchers are working on an even more insidious method. They recently succeeded in manipulating the pregnancies of lab mice using a modified virus. A modified virus that spreads among the animals like disease is to impair their reproduction.