The recent deaths highlight the vulnerable status of the species, which now numbers about 1,500 animals. Scientists don't know how many pygmy elephants previously existed on the island, although it's likely the population wasn't much higher than it is today, said Barney Long, head of Asian species conservation at WWF-US.

This week Malaysian authorities discovered a group of elephant carcasses close together in the Gunung Rara Forest Reserve, located in the northeastern corner of Borneo (map), a Southeast Asian island shared by Indonesia, Malaysia, and Brunei.

"We don't know officially yet how they died, but what we do know is this is an area of forest that is being cleared for plantations, and it's very common