Fio turns five!

Fio is one of the most curious and playful orangutans in our study site in the Sabangau Forest. Born in April 2010, he is now five years old. OuTrop’s orangutan researcher, Rebecca Armson, looks back over his early life and discusses what might be in store for him in the next few years.

Many members of our field team remember observing Fio as a small infant. Adul was the first of our researchers to see the young orangutan. In April 2010, Adul was following a flanged male when he saw Feb, one of our most frequently followed female orangutans. He was delighted to see that clinging to her side was a very small infant – Feb’s first baby! The tiny orangutan was maybe only five days old. Adul later named the infant Fio.  

Fio (1 month old) clinging to his mother, Feb, as she feeds. Photo by OuTrop.

Since then, Feb and Fio have been frequently followed by teams of OuTrop staff, researchers, interns and volunteers.

Over the past five years, observers have been able to see Fio grow up and learn essential behaviours – such as what to eat, how to eat it and how to build a nest.

Fio at 6 months old. Photo by OuTrop.

Like all orangutans, Fio spent much of his first year of life clinging to his mother; relying on her for travel. As months passed by he began to explore more and more, initially clambering in the branches close by to Feb, then slowly gaining the ability and confidence to travel further from his mother.

Young orangutans learn by closely observing their mothers. While Feb was feeding, Fio would watch and try the food she was eating. As a youngster he was unable to feed on many of the fruits without help from his mother – for example it was impossible for him to break open some fruit to retrieve the seed that is suitable for eating. For these more difficult food items he would beg for edible parts from Feb until mastering the required feeding technique.

Fio (1 year old) intrigued by the researchers. Photo by OuTrop.

From the age of about two and a half years old, Fio was able to follow Feb as she travelled, without much assistance. Large gaps in the canopy, however, pose a problem for youngsters; even now Fio will still rely on his mother to cross larger gaps between trees. When struggling he will cry to get Feb’s attention. In response, Feb will wait and assist Fio – bending branches and using her body to form a bridge for Fio to cross.

A young orangutan is fun to watch, especially during bouts of play and Fio has provided countless amusement for researchers over the years. He often hangs upside down from a branch or vine, swinging and twirling, sometimes grabbing a stick and dangling it in the air, or holding it in his mouth. As well as solitary play, Fio often plays with a younger infant named Icarus. The offspring of Indy, Icarus is two years younger than Fio. The two young orangutans often play together when their mothers travel and feed together. Their play is almost always initiated by Fio and includes forms of wrestling, poking and grabbing.

Fio (2 years old) – a very curious and playful character. Photo by OuTrop.

Over time, Fio has slowly learnt and developed essential behaviours, including foraging and nest-building skills. At the age of four he was able to pretty much eat anything that Feb eats and often practised building a small nest during periods when his mother rested or fed for a long time.    

Fio (4 years old) feeding on termites. Photo by Rebecca Armson/OuTrop

Now five years old, Fio frequently feeds in different food patches from his mother, often at a distance of 50 metres from her. But, he is still dependent on his mother; he follows her travel path, sleeps in her night nest and drinks his mother’s milk.

A young orangutan will typically stay with its mother until the age of 6-7 years old. Only when the offspring reaches this stage of independence will the mother reproduce again. We have seen in recent months that male orangutans are already beginning to show an interest in mating with Feb.

In the next year or two we anticipate that Feb may give birth to her second infant and Fio will then be forced to travel and forage independently.

As a male, we expect that Fio will depart from the area of forest that is his mother’s home range. Orangutans adopt a sex-biased dispersal system – while females will set up their home range close by to their natal range, males will head off to a new area.

We are always excited to follow Fio as he reaches independency and we can’t wait to see the large adult male he will eventually turn into!

Fio watches the researchers during a recent follow. Photo Connie Miller/OuTrop