Up to 4 cm. in length, Australia’s Bulldog Ants are the biggest ants in the world and can be found in any part of Australia. They killed a farmer in Victoria in 1988 but this is one of only three deaths by this species. Authorities are more worried about the South American fire ant that has made it into Australia and has been found around Brisbane. Being very aggressive and having a powerful sting they have killed new born calves and birds and are considered quite able to kill people, authorities have gone to considerable trouble to try and eradicate this ant.