Mustelids have a worldwide distribution except in Australia, Antarctica, Madagascar and some oceanic islands. The members occupy almost every habitat including fresh and salt water. These small to medium-sized animals have a long body with short legs. Members belonging to the family Mustelidae include weasel, polecat, mink, marten, wolverine, stoat, ferret, sable, skunk, otter, badger and honey badger. A thick oily, yellow and strong smelling substance called musk is secreted from the glands. Mustelids are mostly solitary animals, though they may be found in small groups. Most species of mustelids are active both day and night. The majority of animals are terrestrial. However, they are also occurred in semi arboreal (e.g. Marten), burrowing (e.g. badger) and amphibious (e.g. otter) states. The otter is described in greater detail here.