These young orangutans are on the loose and in search of food at the Nyaru Menteng rehabilitation centre in Central Borneo.
Aged between two and four years old, they are being cared for by a dedicated team of carers and veterinarians.
They no longer have their mothers to teach them how to live independently in the jungle and must learn from humans instead.
Even feeding time, is a lesson in how to use implements to get food in hard to reach places.
The International Union for Conservation of Nature, which declared Borneo's orangutans critically endangered in 2016, says their numbers have dropped by nearly two-thirds since the early 1970s as plantation agriculture destroyed and fragmented their forest habitat.
Hani Puspitasari, who's been a carer for 10 years, is one of the many women who act as a surrogate mother to teach the orangutans how to become independent.Also read- Crustacean shells may soon be used in medicine
"I learned a lot from orangutans. I was single when I first worked here and now I have children. I learned how to take care of my child from my experience working to care for orangutans here. Both are the same, we have emotional closeness (as mother and child) the only difference is that when caring for orangutans I must be more attentive because they don't have a mother anymore."
Land clearing and poaching has left tens of thousands of wild orangutans dead.
Many of the orphans here were rescued from the pet trade or were found alone in the forest after their mothers were killed searching for food in local plantations.
The UN estimates that over the past 20 years more than 3.5 million hectares of forest have been destroyed to make way for palm oil plantations.
But these orangutans are the lucky ones, they're learning important forest skills so they can one day be released back into the wild.
Another carer Sri Rahayu, who has worked here for 6 years, says orangutans all have different personalities and require love and attention.
"At the present age, they are happy to play and want to be close to us. Often they want to be hugged and held in our arms but sometimes they are more quiet so we have to know their mood every day," says Sri Rahayu.
During rehabilitation, the orangutans are taught how to build nests, select appropriate natural foods and recognize natural predators.
This process starts in 'Baby School' and progresses through different levels of 'Forest School', where each day is spent learning new skills.
The Central Kalimantan Orangutan Reintroduction Program was established in 1999 to provide care and rehabilitation to displaced or orphaned orangutans rescued from areas of habitat loss.
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The facility is located in Nyaru Menteng Arboretum, about 30 kilometers from downtown Palangka Raya.
The programs focus on rehabilitation and reintroduction activities in line with national and international (IUCN) guidelines and criteria.
When an infant orangutan is taken away from its mother, he or she loses a whole life time of early learning.
The Nyaru Menteng Reintroduction Program is managed by Borneo Orangutan Survival (BOS) Foundation, an Indonesian non-profit organization dedicated to the conservation of the Bornean orangutan, established in 1991.
The BOS Foundation manages two reintroduction programs; Nyaru Menteng in Central Kalimantan and Samboja Lestari in East Kalimantan.
As many as 360 orangutans have been released while another 530 are still kept in cages at both Nyaru Menteng and Samboja Lestari, waiting for their release.
With a large population, it takes many professionals including veterinarians.
There are seven veterinarians and two paramedics working shifts at Nyaru Menteng including the vet posted at the forest of Bukit Raya Bukit Baka national park.
Arga Sawung Kusuma, one of veterinarians, says animal health is a key factor in this rehabilitation center.
"We are dealing with a large population in here, at the world's biggest rehabilitation center for great apes so, we must really be careful that if one orangutan is sick, it will not spread to other orangutans because it is very dangerous for the population."
Dependent on the age and existing skills each orangutan has, rehabilitation can take up to 7 years.
Skills acquired by each individual are assessed before moving them up through the levels. Orangutans then progress to one of the pre-release islands, which is a halfway forest for the final stage of rehabilitation.Also read- US fed workers are feeling the pinch real hard
"It was an extraordinary feeling (seeing orangutans finally being released into the forest). Indeed we are very sad that we cannot meet them again but it's okay because our goal here is to care for, educate and train them to be able to live independently until finally they can return to their habitat because that's where their real life is," says Puspitasari.
Two apes were released in to the wild in Bukit Raya Bukit Baka national park last December (2018).
Some orangutans however can never be returned to the wild due to illness or injury and will be looked after here for the rest of their lives.
An orangutan can live for around 50 years in captivity.