Orangutan Stories: Labetty is pregnant... again!

As a tree-dwelling species, observing the re-introduced orangutans in Lamandau Wildlife Reserve is not always easy; with trees comes height and camouflage! Staff were therefore surprised when they noticed that Labetty was pregnant... her third time in six years!

Labetty, 2025

Orangutan pregnancies are not dissimilar to that of humans; there is a gestation period of around nine months, changes occur both physically and mentally, and behaviours become less strenuous, with more time spent sleeping. Though Labetty’s behavioural changes have been far from peaceful!

Mother and infant resting in Lamandau Wildlife Reserve

Labetty was born in the wild in 2007 to ex-captive Lady Di, who had sadly suffered from a miscarriage the year before. 19 years later, Labetty is now pregnant with her third offspring. Suspiscions arose about her pregnancy from physical indications and altered behaviours in the female, but her enlarged abdomen confirmed the news – and we are delighted!

During Labetty’s pregnancy, her behaviour has changed in its own way. Typically indifferent towards the staff around her, paying them little to no attention, Labetty has been spotted chasing visitors of Camp Rasak, where she has been spending much of her time resting.

Labetty with previous infant (Lego), 2025

Our four camps in Lamandau Wildlife Reserve are only accessible by boat; the team arrive each morning by speedboat to begin their day of work. Last week, staff arrived as normal to the soundtrack of birdsong and the stirring of the orangutan carers who sleep at the camp. As they disembarked the speed boat, walking down the jetty towards the call of camp responsibilities, the speedboat driver Anto took a moment to secure the boat.

Speedboat

Soon after, with the boat in place, Anto followed the team down the jetty... but an angry Labetty soon emerged behind him! Less familiar with Anto, Labetty who had been sleeping beneath the jetty began had clambered on top and began to chase Anto! Luckily, Anto noticed her and managed to get clear... a warning nonetheless from the pregnant female!

Labetty climbing aboard a longboat at camp

It is difficult to confirm the reason for Labetty’s aggression, but it is likely due to mood changes associated with her behaviour. All the team are very excited for Labetty’s birth; this will be the sixth wild birth in the past year!

Interesting orangutan behaviour

Firstly, a big thank you to Brigiatta for your monthly donation and Maciej for your donation of $100. As you recently visited Tanjung Puting National Park and Camp Leakey this post should hopefully be of interest to you. In July, we discussed why the orangutan Riga shared her food with her mother, Rani. The reason may be biological or social but what is certain is that it is a rare event between adult orangutans; which is why it was surprising to see it happen again on Sunday – but this time with another twist.

Tom - dominant male

Tom is the undoubted King of Camp Leakey; the dominant male. He doesn’t have to share anything with anybody if he doesn’t want to. On Sunday, he sat down with his bucket of milk and proceeded to slurp away at it with Siswi looking enviously at him. Tut then came up, she had not been to the afternoon feeding so may have been hungry. Tut is Tom’s mother but subordinate to Siswi, so she approached warily.

Tom, however, passed over the bucket without hesitation (and all Siswi could do is continue to look on greedily!).

But what made all this doubly interesting is that it points to an answer to one of the big remaining questions of orangutan research: do they recognise their own parents/offspring? In reality, there is no more reason for Tom to share his milk with Tut than with Siswi (indeed, Tut is not in season but Siswi could be) and yet he did willingly. Why? It would be interesting to think Tom knows his mother and that was why he acted favourably towards her but like so much about orangutan behaviour we still have a lot to learn.

Thank you,

Stephen

PS Apologies for the rain spot on the photo.