This one’s a little camera-shy, folks.

The Indonesian Mountain Weasel (Mustela lutreolina) is a small, isolated weasel species that can be found only on the islands of Sumatra and Java in Indonesia. They prefer to live at elevations above 3,280 feet (1,000 meters) in the tropical rain forests of the islands. Very little is currently known about this species, and all of the information available about Indonesian Mountain Weasels is comprised of what has been learned from 15 specimens and one field sighting.

Indonesian Mountain Weasels have the slender, elongated bodies typical of all weasels, with reddish-brown coats and some pale markings on their bellies. Adults can grow up to 12 inches (32 cm) in body length, with a 6-inch (15 cm) tail.

The diet of Indonesian Mountain Weasels likely consists of the smaller animals that also live within its range, which probably includes smaller mammals, birds, eggs, and insects. It is thought that Indonesian Mountain Weasels don’t have any natural predators other than humans, but not enough study has been conducted on their populations to know for certain.


The mating system of Indonesian Mountain Weasels is most likely very similar to that of other similar mustelids, which means that the males probably have larger territories that overlap that of neighboring females, and he will attempt to mate with them all during the breeding season. This is believed to take place in the spring, from March to May, and after a 30-day gestation period the females will give birth to a litter of at least two young. The baby weasels are entirely dependent upon their mother for their care for the first two months, which is probably the point where they are weaned.


Even though the Indonesian Mountain Weasel has not been widely studied, it is still considered to be endangered due to their tiny range and the habitat degradation that is known to be a problem on Java and Sumatra.

Source for images used in this post.