Dean M. Chriss
The Handsome Couple, Proboscis Monkeys, Borneo

The Handsome Couple, Proboscis Monkeys, Borneo

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Among the strangest, rarest, and most endangered primates on earth, proboscis monkeys live only on the island of Borneo. They are found almost exclusively in mangrove forests near fresh water and are extremely shy. Proboscis monkeys stay in social groups of 3 to 30 individuals that consist of one adult male, several females, and their infants and juveniles. Newborns have a deep blue face and dark fur which changes to the adult colors in 3-4 months. These groups never sleep in the same area on consecutive nights. The males are among the largest monkeys in Asia, weighing as much as 66 pounds (30 kg). Females are smaller, typically weighing half as much as the males, and lack the long pendulous nose.

Proboscis monkeys are one of the best swimmers in the primate world. They usually leap from tall trees into the water in a "belly flop" that does not seem to hurt them. With webbing between their second and third toes, they have been observed swimming fully submerged for 65 feet (20 m). They often outswim crocodiles, which are one of their main predators. Their scientific name is (Nasalis larvatus). Locals call them "orang belanda" which is Malay for "Dutchman".

The population of proboscis monkeys has dropped by about 80 percent in the last 30 years and continues to decrease. Their primary threat is habitat loss. Uncontrolled clearing of the region's rain forests for timber, settlement, and oil palm plantations continues to eliminate huge areas of their habitat. This habitat loss and fragmentation force the monkeys to descend from the trees more frequently, and they must often travel long distances to find food. While on the ground they are easy prey for everything from Borneo's rare and elusive cats (clouded leopards, marbled cat, leopard cat) to native people who consider them a delicacy. With about 7000 remaining they are even more endangered than orangutans. With no government protection beyond laws that are never enforced, and rampant greed squeezing the last money out of the devastated forests, proboscis monkeys will vanish from the wild in short order. They are difficult to keep alive in captivity due to their specialized diets and the stress of captive living.