According to an old saying , a dog is a man's best friend , but in Australia,they can also be his worst enemy.Farms on the edges of the Australian Outback are regularly attacked by wild dogs in search of aneasy meal. the animals , which mostly belong to the dingo species, kill thousands of sheep,and their attacks cost Australian farmers about NT$1.94 billion in lost income every year.In the past, many farmers have paid hunters to track down and kill dingoes, but with the species now at risk of extinction,