Announcing a New Orangutan Pregnancy

By Ahmad Rizal, Research Manager

Hello everyone! Do you still remember the good news that we shared in our May newsletter about the new baby orangutan that we followed? Finding new baby orangutans is one of the most exciting things that can happen at Cabang Panti Research Station (CPRS) and always makes us happy. This month, the orangutan research team is very excited to share some more good news! On August 14th, one of the wild orangutans, Berani, who we have followed since she was an infant, tested positive on a pregnancy test!

Our team first met Berani in 2008, when she was found with her mother Bibi, by Wahyu Susanto, who is now our Research Director. At that time, we estimated Berani to be about 3-4 years old. Berani was a very galak (fierce) young orangutan. She liked to throw twigs and branches, but never seemed afraid when assistants first started to follow her. This is how she got the name “Berani” which means “brave.”

“Berani” the orangutan in 2017.

The team continued to record data on Bibi and Berani for many years. By 2013, it seemed like Berani had become independent from her mother, and she was then considered an adolescent. Then, in 2015, Bibi was seen with a new baby who was later named Bayas! Even now, Berani is often seen “partying” with Bibi and Bayas and playing with her younger sibling. Due to recent genetic analysis, we also now know that Berani’s father is a flanged male named Codet. In recent years we have thought Berani would soon get pregnant as she is old enough and has been observed spending time and having consortships with adult male orangutans.

Berani (upper right) “parties” with Bosman, an unflanged male orangutan in 2018.

On June 10, 2022, one of our research assistants, Jaka (Jak) found Berani in the forest and followed her to her night nest. The next day I joined two field assistants, Hassan and Toto, along with a student from the National University (UNAS) to follow Berani for a full day. That morning we collected a urine sample and I was able to conduct a pregnancy test with that urine. However, the results we got were a little vague (it wasn’t clear how the lines were reading). I think this might be because some rainwater got mixed in with the urine since it was a rainy morning. Once the sun came up and we could see Berani more clearly, we tried to take photos and videos of the orangutan’s genitals and nipples to confirm some morphological characteristics that are usually seen when orangutans are pregnant. However, that first day we were quite unlucky because she always travelled between tall trees and it was difficult to see her. The assistants and I thought maybe there was some swelling in Berani’s genitals and nipples.

That evening, I had a discussion with all the assistants and explained that we needed to try to focus on collecting a urine sample and doing a pregnancy test each day, and see if Berani was showing any signs of pregnancy. We continued following Berani for five days, however it was very rainy each morning which made it difficult to collect urine. I joked that maybe Berani wanted to keep it a secret if she was really pregnant! On the fifth night, Berani made a nest up the mountain, along a trail quite far from our camp, so we let her go and stopped the follow series.

Fast forward to August 13th, Jak found Berani again! After two months since the last time we saw her, Jak followed her to the night nest. The next morning I went with Jak and Toto to Berani’s nest, with a new pregnancy test in hand. We arrived at the nest early in the morning and waited for the orangutan to wake up. The weather was very clear that morning with no rain. Berani woke up around 6am and then immediately urinated. Jak was able to collect a urine sample and then we did another pregnancy test. Wow! The results were positive! We were all so happy.

A pregnancy test taken on August 13th. The two pink lines confirm that Berani is pregnant! Regular pregnancy tests made for humans can be used on wild orangutans – it detects the same hormone, hCG, which is produced at the beginning of pregnancy in both humans and orangutans.

Later in the day we were able to take more photos and videos, and continued to check on Berani’s physical features using binoculars. We could see that her stomach (which is usually big and round already) had grown quite large. We could also see that her genitals looked swollen and her nipples were enlarged, so we felt very confident that she was definitely pregnant. We did another test on her urine back at the camp lab, and again the next day, and the results continued to come back positive.

The field assistants also noticed a slight change in Berani’s behavior. Everyone here knows that Berani is one of the orangutans who travels a lot. However, during these days she spent much more time resting than traveling. This reminded me of following an orangutan, Walimah, while I was here in 2019 to conduct my senior thesis research. Walimah was very pregnant at the time and seemingly spent the entire day just resting and eating.

Unfortunately, after the second day of the follow, we lost Berani due to very strong winds which made it too difficult to see her in the forest. This was disappointing, but we were all very happy with the data we were able to collect for Berani. It is so special to be able to collect data on this orangutan from the time that she was a young juvenile until now, into adulthood, and then see that she is pregnant. We are happy to know that Berani will soon have a little baby that will join our “family” at Cabang Panti Research Station. Berani’s pregnancy is also one of the motivations for us to continue doing research on orangutans, to protect and preserve orangutans and their habitat.

Berani in August 2022. Her abdomen is now even larger than normal!

We are very happy to share this good news with everyone who has continued to support our project. And what a great time to announce this news in August, the month of World Orangutan Day! We are so grateful to continue our partnership with the National University, in collaboration with the Gunung Palung National Park Bureau, in order to learn more about this special species of animal.

Management of Cabang Panti Research Station is conducted by the Gunung Palung National Park Office (BTN-GP) in collaboration with GPOCP/YP. Scientific research is carried out in conjunction with the Universitas Nasional (UNAS) and Boston University.