The dugong is the only strictly marine herbivorous mammal, as all species of manatee use fresh water to some degree. The dugong has been hunted for thousands of years for its meat and oil. The dugong’s current distribution is reduced and disjunct, and many populations are close to extinction.
The Nene is the world’s rarest goose. It is believed that it once was common, with approximately 25,000 Hawaiian Geese living in Hawaiʻi when Captain James Cook arrived in 1778. However, hunting and introduced predators, such as Small Asian Mongooses, pigs, and cats, reduced the population to 30 birds.
The koalas of South Australia were largely exterminated during the early part of the 20th century, but the state has since been repopulated with Victorian stock. The koala is not found in Tasmania, the Northern Territory or Western Australia. As of 2012 there have been increasing concerns about the animal’s sustainable future in the environment.
The Amur leopard is a subspecies native to the Primorye region of southeastern Russia and Jilin Province of northeast China, and is classified as Critically Endangered since 1996 by IUCN. Only 14–20 adults and 5–6 cubs were counted in a census in 2007, with a total of 19 to 26 Amur leopards extant.