Brown Spider Monkey

The brown spider monkey or variegated spider monkey (Ateles hybridus) is a critically endangered species of spider monkey, a type of New World monkey, from northern Colombia and northwestern Venezuela. Its taxonomic history has been confusing, and in the past it has been treated as a subspecies of either the Geoffroy's spider monkey or the white-fronted spider monkey. Like all spider monkeys, it has very long, spindly limbs and a lengthy prehensile tail which can almost be called a fifth limb. The tail has a highly flexible, hairless tip with skin grooves which improves grip on tree branches and is adapted to its strictly arboreal lifestyle. The brown spider monkey has a whitish belly and patch on the forehead, and – highly unusual among spider monkeys – the eyes are sometimes blue.

The brown spider monkey is now a highly threatened species, the population is estimated to have decreased by at least 80% and some populations have already been extirpated. Few remaining populations are of adequate size to be viable long-term. Almost 60 brown spider monkeys are present in various ISIS-registered zoos (mostly in Europe), but breeding success has been limited and no births were reported between May 2009 and May 2010. Habitat loss is ongoing within its range, and an estimated 98% of its habitat already is gone. It is also threatened by hunting (in some regions it is the favorite game) and the wild animals trade. The brown spider monkey is among "The World's 25 Most Endangered Primates", and is one of only two neotropical primates (the other being the yellow-tailed woolly monkey) to have been included in this list in both 2006-2008 and 2008-2010.
A small population of fewer than 30 individuals of the subspecies A. h. brunneus has been discovered in a protected area of Colombia, the Selva de Florencia National Park. This is the southernmost population of the brown spider monkey and the only population found in a protected area.