Orangutans are struggling as massive amounts of rainforest in Southeast Asia are burned off, or chopped down, to make way for palm oil.

Along with habitat loss, the intelligent and slow-moving great apes have to deal with poachers and locals who eat them or keep them as pets.

There are as many as 100,000 wild orangutans left in Borneo, and less than 14,000 in Sumatra.

They only have children once every eight or nine years, and scientists fear extinction looms for those in Sumatra.

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Orangutans in Sumatra could be the first great ape to go extinct.

The red-furred, long-armed ape that shares 97% of the same DNA as humans are only found in the wild in Southeast Asia. As they're poached, and the rainforest is decimated to make space for palm oil, their future is uncertain.

There are still thousands of wild orangutans in Borneo and Sumatra, as many as 100,000 in the former and less than 14,000 in the latter. But they only bear offspring once every eight or nine years. It's one of the slowest birthing periods of any animal, and, according to The New York Times, "scientists fear that the population is in a death spiral."

Orangutans are smart. In 2010, Executive Director of the Orangutan Land Trust Michelle Desilets told Monga Bay News, "if you give a chimpanzee a screwdriver, he'll break it; if you give a gorilla a screwdriver, he'll toss it over his shoulder; but if you give an orangutan a screwdriver, he'll open up his cage and walk away."

But smarts alone aren't enough. They rely on rainforests for survival and spend about 95% of their lives in trees. As the rainforest is decimated, so is their future.

Here's what life is like for wild orangutans, in photos.