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,this approach has become unpopular