Kirsty and Ben: August 2007; July 2007

Mark: May 2007; April 2007; March 2007; February 2007; January 2007; December 2006; November 2006; October 2006; September 2006; August 2006; July 2006; June 2006; May 2006; April 2006; March 2006; February 2006; January 2006; December 2005; August 2005; July 2005

Helen: September/October 2004; August 2004; July 2004; April 2004; March 2004; January/February 2004; December 2003; November 2003; September/October 2003; August 2003

August 2007

This month has been a rather strange month at camp with various goings on, both in the forest and at camp. We have encountered some very interesting behaviour from our local orang-utans, rediscovered what we think are some long lost friends and come across several strangers to these ’ere parts!

The month started with a real surprise…

31/07/07 to 02/07/07 – Whilst searching the forest on the final day of July, we were reaching the point of midday when a female with a baby were spotted just inside the grid by Santi. We were having radio issues on this particular day and he was out of contact with everyone due to a dodgy radio antenna. Despite this Santi, (being the quick thinking individual we all know and love) took it upon himself to collect this precious data alone. As the rest of us were returning to camp after what we thought was another fruitless day, Santi still hadn’t arrived. I was beginning to get worried by 17:45, when from the jaws of the forest, Santi emerged into the dusk lit camp with a grin as wide as the new moon, had he been successful?

As Santi relayed his account of the day and we looked over the data sheets, the follow became more and more interesting. The female and infant, who at the time we thought were Inda & Isabella (a two year old infant female) had been alone in the forest eating the usual diet for this time of year (termites, Pandan, leaves and bark). At around 15:30, Santi heard a noise close by and into the nearby canopy sauntered an unflanged male (Romeo). This however was not a social visit; his motive was far more malevolent. He wanted something and if it wasn’t offered willingly, he was going to take it.

The next day, August 1st, early in the morning, five of us set out to follow the three orangutans, 3 to take data on the female and 2 on the male. When we finally arrived at the nest site, we could see that Romeo had nested with a great vantage point over her nest, she had been trapped. Romeo was first to arise at 05:45. For an hour he fed in the tree directly above her, until finally he headed down to climb into her nest alongside her. This was met with a series of whimpers, but she remained in her nest out of our view, what was she doing or thinking, was she scared? Romeo was first to leave her nest but within 10 minutes they were co-feeding on fruit in a large Ponak tree no more than 10 meters from each other for nearly 2 hours! Whilst they were all feeding in the tree we noticed that the infant was actually not a female at all! This couldn’t be Inda and Isabella and we don’t have any other females with a male infant of this age, she must be a new female to our research so we named her Juliet (not quite apt, for reasons to become apparent) and the infant, Julius.   

The day progressed with a strange game of cat and mouse, at some points it was obvious that Romeo was chasing Juliet but at some stages it seemed she was willingly following him. The reason for this became apparent at about 13:30 when, for the first time the pair moved more than 20 meters from each other. Romeo carried on ahead of Juliet and for a time it seemed as though he was leaving the mother and baby in peace. As she turned the opposite direction and made a belay for an escape along the ground, her suitor swung around and came crashing through the branches to re-accost his valuable bounty, caring not about the two hapless researchers in his path, nearly crashing right into them! Maybe she knew that any attempt to escape was futile. He was much quicker than her and any attempt would only serve to antagonise him, possibly endangering her young infant.

Romeo and Juliet mating. Julius can be seen clinging on to his mothers fur. Photo: Ben Buckley

Finally at 15:14 Romeo made his intentions towards Juliet clear. As she was feeding on some leaves about 12 meters above the ground, Romeo advanced, she began to whimper again just like earlier in the day at her nest. After a series of grabs and bites at her arms and fingers to force her to turn around, he finally managed to have successful intercourse with her. In the mêlée the screaming infant, Julius, made a very brave effort at getting in the way of the attacker and help his mum, but to no avail and was nearly sent crashing to the ground in the process. From this display he will definitely be a contender for dominant male in the future! The whole episode lasted for no longer than 10 minutes and for the rest of the day they stayed within 10 meters, mostly co-feeding in the same tree until they were both safely in their night nests by 17:00 (although Romeo was in bed a good 20 minutes before Juliet and Julius). Maybe they could have made a run for it then, why not?

The saga continued the next day with this pair. Romeo rose and began eating 2 hours before Juliet who was nested in a nearby tree. Although Juliet was awake, she again didn’t leave her nest for 2 hours, probably dreading another day like the last one with Romeo, wishing that he would get bored and leave her in peace. Unfortunately for her he did not. The day progressed much like the previous, long feeding bouts and the two orang-utans never more than 20 metre’s away from one another. At one point Romeo left his feeding tree northerly and minute’s later Juliet, south. Again, Romeo checked his companion was in tow and when he saw her disappearing in the opposite direction restarted the pursuit. This was nearly the last thing we saw of this interesting interaction as the two of them disappeared into the distance with deep Pandan (a large grass with sharp thorns) blocking our path, disappointingly we would have to imagine how this scenario would pan out.

19/08/07 to 22/08/07 - Our next forest companion was Bengy, an adolescent male of about 12 years, not seen since April 2006.  He has been seen at the southern edge and in the centre of the grid on the two previous occasions he was followed, being spotted this time between these areas. However his range is unknown as he frequents the grid rarely. Now this little fellow is a bit of a handful to follow, jumping all over the place, travelling countless metres at a time, with the occasional bout of kiss squeaks (even at the squirrels for making too much noise!) As if he doesn’t give us too much to do already, he usually nests pretty late after 5 pm, meaning a nice tired walk home in the dark. Looking at these four days following, he still hasn’t changed; as he crossed the grid towards the river in a general north-westerly direction, he seemed to snack on nearly anything edible in his path, making us work very hard to follow him with not a moment to rest. Sometimes you wish you were following a large male whom had happened upon a fruiting Kenari tree!

 26/08/07 to 27/08/07 – This follow started in a very unfamiliar way indeed, as  three orang-utans were found at pretty much the same time, two in one place by me and a flanged male by Twenti. It was decided that we should go with an un-flanged male called Zeus, as they are less regular visitors to the grid and hence less studied than the others. The flanged male was also close to the edge of the grid, so we had a better chance of collecting more data on Zeus.  The other orang-utan nearby was Bengy and as we already had data on him this month, it was best to concentrate on the others, phew…

On the first day Zeus led us right out to the western edge of the grid, travelling about 1 km in one afternoon never eating for longer than twenty five minutes in any tree. So the next day it was a very early rise to get to the nest before Zeus left. As I found myself a comfortable spot under his nesting Terantang tree, I came across a rather morbid discovery; hidden in the dead leaves near the base of the tree was a mandible of a dead orang-utan.  Unluckily for me Zeus obviously spotted me directly below him as I searched the surrounding area for the rest of the remains and managed with pin point accuracy to lay a huge crotte right on my back (not what you need at 5:00 am with a full day’s follow ahead of you!) I was unable to find any more remains or any other pieces of the forensic puzzle at the scene before we left, but I still wonder what had become of this poor orang-utan.

For the early part of that morning Zeus took it fairly easy, not travelling too far with two separate feeding bouts in a Lunuk Tingang (large Fig tree). He shared the tree for about 10 minutes with a group of three gibbons (Hellboy & Co) and several birds, showing restrain with his irritation at having to share his meal with only five kiss squeaks. Later, Zeus took us up North, towards the river through some of the nicest forest in the grid, with a clear under-story and larger trees offering some great views of him (although he did seem a little annoyed by this fact, often staring at us and giving a couple of K-squeaks in our direction. But it turned out by midday, having been followed by us for the whole morning, I think he was very thankful for the fact that we were with him…

As Zeus was busily eating leaves in a large Ehang tree, keeping himself to himself, from the distance appearing into view with a crash, bang, wallop rushed another slightly larger male, obviously with the intent to chase if not attack Zeus. Luckily for Zeus we were right in the other orang-utans path and although he was not afraid of Zeus, he took one look at us and stopped right in his tracks. This gave Zeus the perfect opportunity to flee and flee he did, as fast as his long arms could carry him. Little to say, we lost him as he raced away. But we were left with a semi-flanged male acting like he was completely un-habituated, kiss squeaking continuously and not even stopping to eat, very unlike the other orang-utans who visit us in the grid (they are usually so well behaved!) After only 1¼ hours we had travelled right to the NW corner of the grid, nearly into the river sedges, with no feeding data, hundreds of Ks and very obvious irritation, we decided to not upset this clearly un-habituated drifter any longer and returned to camp to see if we could identify him from the photos (we couldn’t, he was a stranger).

28/08/07 to 29/08/07 - The final days following of this month were with a grid favourite, Indah, an old female probably over forty years old! She has had many infants, Isabella her most recent, was born November 2005. She is often found with her last infant Indy not far away maybe taking lessons in motherhood or possibly jealousy of the new little one! Bernie and a volunteer had seen such an occasion earlier in the month whilst walking back from a gibbon follow, a rather lucky chance by all accounts, as orang-utan’s are predominantly solitary, excluding times of mating and this kind of behaviour is relatively rare.

 For the first day Indah predominately ate liana leaves, that was until she found a Kenari tree, (a real favourite at this time of year) and gouged herself on the loud cracking fruit for a couple of hours until bedtime, with Isabella never too far away under the watchful eye of mum. Although well habituated and usually easy to follow, after a very lazy morning the next day, she managed to do a good disappearing act into the wind rustled trees and was lost. I think Houdini would have been impressed!  

July 2007

WELCOME to the first edition of the new and exciting Orang-utan Diary coming to you from Setia Alam Jaya, meaning “loyal to nature”.

Firstly we would like to introduce you to the current Orang-utan Behaviour Team:

Kirsten Manduell: Temporary Project Manager and Masters Student. A bit of a mother figure hence nickname ‘Mum’ around camp.

Ben Buckley: Project Manager in Training, in his infancy with the project & still learning the various ropes.

Twenti Firsman :  Has 3 years experience, an amazing 3000 follow hours & has followed more OU’s in the Sabangau than anyone else.

Dewa: Has been working on the project for a year now & proved himself a valuable member of the team. He does think Mozart (one of our flanged males) has a vendetta against him. We’ll have to see!

Ambut: Has only been with us for 6 months but his forest knowledge, tree climbing exploits and fantastic enthusiasm have already been priceless.

Santi: Has been involved in the project longer than the furniture (maybe not Twenti though). If anyone can correctly identify more tree species in Sabangau we have yet to meet them.

Yudhi: Chips in when not looking after the volunteer needs, prefers working with the gibbons, our loss is Bernies gain!

The first few days of July, were spent doing much needed repairs to the boardwalk, a task deemed well overdue since the entire team must have tumbled or slipped spectacularly at least once, usually warranting a slot on You’ve Been Framed.  By the fifth day planks were on the whole repaired and we were back to behavioural work, searching for our often illusive Orang-utan friends.

On the 6th whilst the behavioural team were out in the forest, Mozart, a flanged male turned up at camp for a quick visit to one of the fruiting trees that surround camp. Fortunately, Santi and Twenti were on hand to follow him and accompanying them on her first follow Amy, one of the OuTrop volunteers ventured into the forest on his trail. They managed to follow him for about 4 hours before he went too far out of the research area and was subsequently abandoned.    

7th and 8th - No success

9th - GREAT success

It was the morning of the 9th as the forest was just calming down after the usual dawn melee, when Ben bumped into a happy band of volunteers in the forest. They were returning to camp from an early morning forest excursion listening to gibbon song when they had happened upon a young female named Feb. She is an 11 year old female full of character whom you will no doubt become familiar with over the months, as she frequents these pages with her countless exploits! Kirsten and Dewa (also out searching) were radioed and rushed to the site she was found notchantly eating.  Together the three of us quietly followed her until she nested in the late afternoon with Ben training on taking the behavioural data under the watchful eye of Dewa and Kirsty gathering her precious data on locomotion!

During the follow she stayed in the same place for nearly 5 hours, very unusual for Feb who usually makes us run from tree to tree as she snacks for literally minutes on everything – a definite believer in the “eating little and often diet”! Having began eating the fruit of a liana called Kalalawit Hitam (a vine fruit orang-utans seem to love), she then constructed a day nest in the very same tree in which the liana had wound its way up to the canopy and continued intermittent grazing from there. A few feeding bouts later and not far away in a Ponak tree, she was asleep in her evening night nest and we slipped away. As we wended our way home we discussed this behaviour and after dismissing this being leniency on her behalf for the benefit of the new trainee, we agreed that she seemed a bit out of sorts, a bit lethargic and not her usual perky self. We would see how she was tomorrow; maybe something would give us a clue?

10th-

The next day we left camp at 4am in total darkness in order to reach Feb soundly sleeping in her nest. It is necessary to reach the OU’s before they get up – often just after sunrise, so we don’t lose them. This time we took a volunteer (Libby) with us so she could see how our research is carried out and increase Feb’s worldwide fame.  Feb left the nest at 05:20am and made a beeline for us where she performed her morning rituals by promptly trying to poo on our heads!  Fortunately, being a little more awake than her we managed to scramble out of the way in time. Phew!

She milled about in the morning going back to many of the same trees she had been in the day before, as they all had plenty of fruit left in them from yesterday’s feeding bouts.  Today’s menu included a fig (Lunuk Punai) for a couple of hours, the same Kalalawit Hitam liana as the day before, termites dug out from some rotten wood she found on the forest floor, Jelatung bark and finished off with some large leaves.  We weren’t really sure what the leaves were at first so we moved a bit closer to get a better look, on closer inspection we were very surprised to see that she now had a layer of green foam around her mouth. She then spat a ball of chewed up leaves and saliva into her hand and amazingly began to rub them on her upper arms! We took a sample of the leaves back to camp to get them identified and analysed, we definitely needed to know what these leaves were and why she carried out such interesting behaviour with them; was this medication for whatever was affecting her yesterday? She carried on with this ‘herbal bath’ for about 30 minutes on and off and then made a quick platform and lay down for a short while with the sticky green leaves still clinging to her upper arms. After her rest she made her way back to the same Kalalawit Hitam and ate there for a few hours again.  She made another day nest and carried on eating whilst reclining in her nest – very much a Roman on her day bed.  At about 2 o’clock that afternoon we heard some crashing nearby and then we noticed another OU (unflanged male) sitting in a tree nearby looking at us.

After some wrangling we decided to follow him as it has been a long time since we had the opportunity to follow an unflanged male and collect data.  The unflanged male is called Orson and the behaviour he exhibited gave us the feeling that he seemed a little nervous of us following him although he didn’t kiss squeak at us, probably because we hadn’t seen Orson in a while so he had to get used to these strange creatures following him again. We stayed with him until he made his night nest in the afternoon – before which we revisited the same Kalalawit Hitam for the third time in two days! Not that we were complaining as the best sitting spots had already been established!

Early the next morning we went back to his nest to follow him again.  It would appear that he is also a follower of the “eat little and often diet” with 32 different feeding bouts in one day.  Not surprisingly we also had an unusually large number of faecal samples to collect that day!  We stayed with Orson for another full day and then on the 13th Twenti, Ambut and Kirsten went out to follow him.   In the morning he travelled off after a feeding bout.  Kirsten went out in front to collect her data on locomotion when he came charging back towards her looking like a frightened mouse.  Ambut spotted a flanged male on the ground – he was very quiet and surprised us all!  Orson ran away so quickly we thought we would most certainly lose him so we switched OU’s again!  The flanged male, we think is Leonardo, he is newly flanging and only has very small cheekpads.  He was a little bit aggressive and tried to push a dead tree stump on Ambut, fortunately it didn’t land on him!  He kiss squeaked at us so much it nearly drove us crazy.  He also has the longest kiss squeak we have ever heard!  However, in spite of that both Ambut and Twenti though he was a very handsome OU! We managed to stay with him for 4 days before he went too far out of the research area and had to be abandoned.

17th July – Back out searching again!!! No Success

18th July – Feb Again! 

Ambut found Feb quite early in the morning so Kirsten and Ben who were also out searching went to find them both.  She seemed like her usual self again and ate a few different things that day including ants, termites, leaves and a few different fruits.  The next day Ambut and Kirsten went out to follow her.  She made a day nest at about 8h30am but didn’t stay in it very long.  She ate lots of different things again including another marathon Kalalawit Hitam session which lasted about 3 hours.  She went a bit mental at a bird that was making a racket and kiss squeaked lots at the bird – although the bird took no notice of her at all.    She had travelled quite near to camp throughout the day and we could hear the people at camp playing badminton.  Still at least we wouldn’t have far to go in the morning… The next day another OuTrop volunteer (Andrea) came out with us.  After Feb woke up she went to eat the bark of a Jelutung tree and both Andrea and Kirsten were stood underneath the tree trying to get a better view when once again she tried her best to drop one of her smelly little presents on our heads.  However, due to super quick reaction speed by both of us we managed to get out of the way just in the nick of time!  She then went to eat…. you may have already guessed it…. the same Kalalawit Hitam liana from the day before.  She stopped there for about 2 ½ hours which was a bit annoying as we couldn’t really see her in the tree.  However, she was nice to us and came down quite low to eat some termites really close to where we were so we could get really good views of her.  After she made her nest that afternoon we decided to abandon Feb once again in order to search for a different OU.

Most of Setia Alam camp were heading off on a river trip for the next week so there would only be Ben, Kirsten, Dewa and Twenti holding the fort on the orang-utan front!  Over the course of that week there was also some phenology work going on so for a few days our time was taken up with that.  By the 23rd we were back out searching again but it wasn’t until the 26th when we found another OU.  Twenti had come across another OU who was travelling rather quickly on the ground and then lost as Ben and Kirsten had already headed up to meet him we decided it would be a good opportunity to sit down and have lunch together before heading of on our own to search again.  As luck would have it (and the superior hearing of both Twenti and Kirsten) we heard what sounded like an OU eating termites.  The three of us went to investigate when we came across Beethoven sat on the ground.  Beethoven is a flanged male and possibly boss in the area.  He is followed reasonably regularly whenever he is “in town” and was totally unperturbed by our presence.  He ate a few different leaves that afternoon and did one fantastic long call before making his nest and settling down for the night.

27th –

The next day Twenti, Ben and Kirsten went out to follow him again.  When he woke up he made a noise that sounded like he was about to long call but ended up just being a bit of a grumble.  We could hear another OU was around the area but we never saw it and its presence didn’t appear to be bothering Beethoven too much.  He long called 3 times that day but none were as impressive as yesterdays.  However, he did some fantastic exhibitions of strength and agility when pushing an enormous dead tree stump over half of which ended up upside down well and truly stuck in a hole made in the peat (Kirsten makes a note not to mess with Beethoven).  He also was very precariously balanced in a large Ponak tree at one point and we were a bit worried that he may fall out and land on us – but he’s the man and knows what he is doing!  He ate quite a lot of different things and we were thinking “oh no, not another one” but this is mainly due to the fact that there is very little fruit around at the moment so the   orang-utans are having to eat lots of leaves and termites in order to supplement their diet. He long called 8 times and travelled quite a bit on the ground.  We very nearly lost him at one point due to a large group (about 20) red langurs which were all around us.  We managed to find him again quite quickly and stayed with him until he made his nest. He had travelled very far south by this point so we reluctantly had to say goodbye to Beethoven as we wouldn’t be following him tomorrow.

29th -

On the 29th Mozart again came close to camp as he did earlier in the month. He arrived fairly early in the morning at 07:15 just as everyone was awaking after the previous night’s fancy dress party, some nursing slightly sore heads. He gave quite a display to all the camp including the volunteers, swinging around in full view in the trees behind our badminton court – a great photo opportunity! Our on-site gibbon behaviour manager Bernat Ripoll accompanied Twenti and Ambut for a very impromptu follow to get some orang-utan follow experience, he chose the right day as Mozart didn’t move too far this day circling camp and making his night nest no further than 500 meters from camp. Again the focal orang-utan, this time Mozart visited quite a few different feeding plants in total 15 different lianas and 3 trees, not giving a long respite for the following team, eating mostly leaves probably due to the low number of fruiting trees in the forest at the moment. This didn’t stop the guys and they followed him all the way to his night nest at 16:10.

30th-

It was great that Mozart nested so close to camp the night before as it gave us a lie in until 04:00! This time we had another of the volunteers, Mike with us. After rising from his nest at 05:44, in the course of the day he ate mostly leaves with an accompliment of bark and a sprinkling of fruit to add a little “je ne sais quoi”. Mozart can be a bit feisty as Dewa knows and in an otherwise normal day had a moment of anger, probably borne out of frustration with having 4 gawping humans staring at him, I think I would be the same! As he was quite low in the trees snacking on some leaves he noticed us clipboards in hand and with a determined kiss squeak and a crash of branches made a belay for us stopping only meters above us. With us cowering below his might I am sure I saw a wry smile spread across his wide face before he continued on his way, probably very pleased with himself.

31st

See August for this thrilling 3 day trilogy!

May 2007

We had quite a lot of follows his month and a lot of full days, but only 3 OUs, and one of them only for a day! Ideally, it is best to try and follow a number of individuals from each age-sex class every month, but the density of OUs in Sabangau is low and individuals frequently leave the area for varying periods of time, so unfortunately this is not always possible, as was the case this month. There just didn’t seem to be any other OUs around – we heard very few long calls and those we did hear were all from quite far away, and none of the gibbon research team, or researchers doing other research bumped into any OUs other than the ones we had already found.  Feb bumped into the adult female Viola on 23rd, who we hadn’t seen for a long time. Last time we saw her, we did think she might be pregnant, and this was confirmed when we saw the small Isabella-size baby she was carrying around. Unfortunately, Viola then left the study area and had to be abandoned. 

Probably the most interesting behaviour this month was Feb eating bird eggs (a behaviour witnessed elsewhere, but never before in Sabangau). We have seen her rummage through nests a few times, but this was the first time she has been seen actually eating eggs. Kirsty and I saw her pull a small (6m) tree towards her with a cup-shaped nest in it and put her mouth into the ‘cup’. She then let go of the sapling and moved off a couple of metres and I looked through the binoculars and saw a light-bluey colour egg-shaped object about 1.5cm long in her mouth, which could only have been an egg. She then moved and our view was obscured, but we had a look below the tree and couldn’t see any shell remains, so we think she must have eaten the whole thing, shell and all.

Feb did some pretty neat precision snag crashing while looking for termites – she was hanging most precariously on a very flimsy branch and could have been easily knocked down had one of the snags fell the wrong way (which could easily have happened due to the amount of lianas wrapped around the snags/in the area) and so had to assess quite carefully where they would fall. Although anecdotal, this seemed like some pretty intelligent anticipatory behaviour.

The Radio Visit

An Indonesian radio station based in Jakarta came to camp on 28th and interviewed my colleague Laura Graham and I about the forest here, our research and conservation issues here. I spoke to her for a bit about orang-utans, what it was like to work with them and their conservation (much the same sort of stuff as you’re reading in these diaries!), and Laura discussed her research on forest regeneration. Unfortunately, it’s not possible to listen to this on the net, so you’ll just have to take my word for it that we were great!!

April 2007

This month started off with real difficulties in finding OUs, but then we found Feb just before Easter and actually managed to get a lot of follows in (21, including 13 from nest-to-nest). 10 of these were with Feb, 6 with Indah, 3 with Cleo and 2 with the flanged male Jupiter. Feb was going to bed really early, but the rest were all going to bed quite late – does this represent differing responses to the obvious food shortage at present? Feb is definitely different from Ella 2/Indy: she is noticeably larger and more adult like.

Feb kiss-squeaked quite a few times at a pig on 16th. We’ve actually seen this a fair bit from smaller animals and Indah, and this must be related to the predation threat that pigs pose to OUs. Feb then went out of the grid in between T1.3 and 1.6, which is most unusual for her, as she normally lives much further north. There was a potential incident of Indah encouraging Isabella to learn how to solve travel problems for herself on 25th. Indah crossed gap using a liana, but Isabella remained on other side of the gap. She clearly wanted to get across and started crying when she couldn’t bridge the gap. Indah looked and seemed to weigh up going back to get her, but obviously decided to leave her to find a way cross on her own, which she eventually did. Isabella was also seen biting off pieces of jelutong bark (though not actually eating them). Indah then met up with Cleo near T1.6 (one of the few times we have ever seen those two meet), so we followed both at the same time for a couple of days. Cleo was quite seriously hounded by Jupiter on 29th – she hid up the top of a tall tree and he hovered around beneath her, even moving up into/very close to the canopy of the tree she was in. Cleo cried quite a bit and was clearly scared of this male (this could be either because she was scared for Chivers’ safety and/or of a possible impending forced mating). He left in the end without mating her. Unfortunately, we lost her in the confusion when they moved off, so we were unable to keep following her and see whether any other males are hassling her. Chivers still seems a bit young (and pathetic!) for her to be ready to conceive again, though maybe she is just at that stage where she is almost ready now and all the males are checking her out to see when she will become receptive again.

The NBC Visit

Indah’s, Sabangau’s and my TV breakthrough on the other side of the pond went well. The American NBC came to camp on 28th and we were fortunate enough to find Indah a few days before they arrived and keep her until they were here (well, until about 2 hours after they left, when she vanished mysteriously in a puff of smoke!). They were from the news team and were shooting for the Today Show. The forest was really wet still and, though very experienced filming around the world, the film crew were all new to working in the forest, so much fun was had by all (though I’m not sure that they would all say the same!)!! This show was broadcast on NBC on 14th May 2007. The link for this can be found by clicking on the “In search of orangutans in Borneo” link on this NBC Page: and a narrative from Ann Curry, the show’s anchor can be found here.

March 2007

We had a reasonable number of follows this month and, quite surprisingly, a good number of full-day follows (9, with most being on the adolescent female Feb, who is resident in the study area near camp). Beethoven (the king!) turned up for a few days after not having been seen for a while and Mozart turned up near camp gain a couple of times (and was then predictably lost/went out the same day). Increment weather made searching difficult between 17-28th (my very bored assistants and I went 7 days searching straight with nothing!). Ella 2 (most probably, we were sure this wasn’t Indy, as whenever we see Indah, Indy is still there and this OU was followed for 9 days this month, with no sign of Indah) with Feb one day – although the two are easy enough to distinguish when seen together, it would be easy to confuse them if seen apart. Accurately identifying individual OUs can be incredibly difficult and relies on physical appearance (plus behaviour and location found in, to an extent, as these can vary in the same individual) – trouble is, all these adolescent females all look the same unless you can see them together!! We therefore have to take great care when trying to identify animals. Hopefully genetic analysis will get rid of the remaining confusion we do have!

I saw an old (1-2d, probably) nest in one of Ella 2’s ehang feeding trees (this tree produces sap, which causes serious burns to human skin – I know this from personal experience, when it turned the skin on my hands black and stung for days!!). While there may be chemicals in the saliva that neutralise the acids in the fruit that they eat, how can they nest in ehang trees without burning their skin?? This is a question we don’t know the answer to, unfortunately. Mozart built a roof on his nest (re-built) on one day to protect him from rain, which isn’t a very common behaviour here (though umbrellas made from leaves are used frequently). Ella 2 is still hiding from jelutong men! I wonder if she does this when we come along too (this might explain the dearth of OUs between 17-28th!) or whether she recognises the difference between us and jelutong men, due to our more camouflaged clothing and unobtrusive manner (important factors when habituating OUs and other primates to human presence).

February 2007

This was another month with a reasonable number of follows, but more full-day follows than previous months, chiefly because of Indah and Indy (we rarely seem to be able to get anyone else to nest for more than one day at a stretch now!). Mozart, although easy enough to find at the moment, is particularly hard to keep hold of: if he doesn’t go out (which he normally does), then he’s normally lost on the ground – the bugger!! Feb was an exception: we had a couple of decent days to nest with her, with one day where she was most un-Feb-like and only ate from 8 trees, including one bout of almost 3 hours! Infants and adolescents often feed for very short times on lots of different food trees, which is fine for them, but gives us very little rest and leads to very tired researchers! The only other data was a couple of half follows on Cleo and Romeo. With the exception of Mozart, there haven’t been any flanged males around all month; we only heard a couple of long calls all month (while following and doing other work), and these were all from a long way away, indicating that there weren’t any flanged males in the area for any length of time (and not that we’re just useless at finding them!).

The most exciting event of the month was without doubt Cleo being mated (which Dewa and Andrea, who were out doing other work at the time managed to catch on camera, though the quality wasn’t that good, unfortunately). From the film it looks like a fairly classic uncooperative mating, with growls of objection from Cleo etc., though it doesn’t look like Cleo fought that hard. Possibly she was worried about putting up too much of a fight because of her infant Chivers, who was nearby the whole time, but not in contact with his mother (I had doubted it was Cleo and thought maybe Viola instead until I saw Chivers on film, which confirmed Cleo’s identity, as she is the only female with a male infant in the area).

January 2007

January was another month with a reasonable number of follows, but very few full-day follows. Again, this was mostly due to OUs being lost in the rain/ground or travelling outside the grid and having to be abandoned. No matter how hard we try, we just don’t seem to be able to hold onto them at the moment!! We did have a few follows on Drake, Mozart and some unknown flanged males, and the return of Jupiter (albeit temporary!), who we haven’t seen for a while and thought may be the king at one point, so we still managed to get some data! The rest of the data were on Cleo, Feb and Romeo (an unflanged male, named after his rather uninhibited advances on Indah when we first met him!).

While I would argue that everything about orang-utans is interesting and watching endless hours of fruit eating is a great way to spend a day, not everyone would agree!! For those expecting constant action of the type seen in chimpanzee and other primate groups, orang-utans may disappoint, but once you start to delve in a bit deeper, they are truly fascinating animals (even the hours of fruit eating – well, I should hope so at least, being as my PhD is focussed primarily on feeding behaviour!!). So, for the action seeker, there’s not too much to report for this month (though there was some fascinating fruit eating for me!!). While following Feb on 12th, another OU we bumped into made those threat calls again (which I mentioned Cleo making before), but not sure if at us or Feb. Feb seemed to be a bit upset by a jelutong man (and seemed jumpy altogether) – his presence may have upset her and then caused her to KS at us lots.

December 2006

A bit of a mixed bag this month, with quite a few follows but only one full-day follow, largely because of orang-utans being lost in the rain and lots of orang-utans going outside the grid. We collected data for a few different flanged males, 4 half days on Cleo (good, considering how rarely we see her nowadays!), Leonardo and Feb. People started going off on holiday for Idul Fitri (the end of Ramadan) after the middle of the month (and I was stuck in town extending my permits – the joys of working as a foreign researcher!!) and the few remaining assistants had no searching success, so there were no follows after 20th.

Nugget was in a bit of a squeeze when followed at the start of the month. He was surrounded by other flanged males on all sides and was very quiet (no long calls). He eventually ended up running away on the ground from Mozart, who was long calling nearby. Wuss!! We then switched focals to Mozart, who now has a pretty good long call. He’s still a bit small for a flanged male though. Cleo didn’t really do anything interesting while she was followed, though Chivers (her male infant, born in 2003) is a bit bigger and spending a bit more time off his mother than before (but still travels on her when travelling long distances). The new flanged male we followed on 6th was unhabituated and built his nest incredibly high for a flanged male (about 30m) – I’d never seen a flanged male build a nest anywhere near that high in this forest!! Dewa had a near-death experience when following Leonardo, who pushed a snag (dead tree) over right near him, missing him by inches!! Feb was quite perturbed when hounded by lots of macaques. It’s unlikely they would attack her, but they travel in large numbers, males can attain a reasonable size relative to an adolescent female like Feb and they can be aggressive, so are probably best to avoid!

November 2006

Most of the data this month was on Mozart, and none of these were full-day follows, as he constantly went to the ground and/or out of the grid, and so was frequently lost, often within just a few hours. We still got some good data though. There were a few days on Indah, before she went out of the grid past THH. The only other OU followed this month was a new flanged male we named Nugget (who I unfortunately don’t have any pictures of). He is only small, with small cheek pads and throat sac, and looks like he has only just turned into a flanged male.

Mozart turned up at camp a lot again, which is where he was found most of the time (a real luxury for us, as it saved hours/days of trekking through the forest trying to find animals to follow!). He long called for the first time on 27th, and his long call was quite loud, but not very long. Possibly he was scared to make a full-length call because he may have attracted the attention of other flanged males, who might have come running to give him a physical reminder that he’s definitely not yet at the top of the pecking order! He was also seen in his first fight on 9th, with an unidentified flanged male (who may have been new to the area), which, surprisingly, he won! Indah seemed quite jumpy this month, with researchers and more specifically with pigs (which have been known to kill OUs) and macaques, both of which she tried to hide from. This could be because she was feeling unwell (one day she was very lazy and had lots of leucocytes in her urine), but I think is because Isabella is now spending more off her mother and Indah is scared for her safety. Isabella was seen drinking from a water hole in a tree with her mother.

October 2006

We had a few days on Indy at the start of the month and one day on Indah at the end (as Indy seemed to be eating different things than Indah at the end of last month, but they were both eating essentially the same stuff this month). Drake was around quite a lot and followed on a few occasions, although we didn’t actually manage to get any full days on him, annoyingly (anyone thinking that following orang-utans is a simple matter of dawdling through the forest, stumbling on an orang-utan and idling along behind taking data would be very mistaken – finding, following and avoiding losing these guys is not for the faint hearted!!). Apart from that, had a couple of days with Ella 2 and some good unflanged male follows (a real rarity recently!!) with Romeo towards the end of the month. Searching was halted after Idul Fitri (24th), so that we could work on repairing the boardwalk (which was badly needed!).

While out fixing the boardwalk, strange crackling noises were heard from the forest edge. This turned out to be a forest fire burning through the sedge only a couple of hundred metres from camp!! This year has been an El Niño year, which means that the dry season here was much longer and drier than normal. The peat on which this forest stands burns very well when dry, which leads to large smoke clouds over much of South-East Asia, the release of massive amounts of CO2 and loss of forest cover (especially in secondary forest). The CIMTROP Patrol Team (Fire Attack Force) were called immediately and, together with our staff, worked non-stop for 5 days and nights with virtually no sleep to extinguish the fire, and prevent it reaching camp and burning large swathes of forest. Peat fires are incredibly difficult to put out, as the peat actually burns below the surface, and so it was only due to these guys’ extraordinary efforts and the great knowledge and experience of the CIMTROP Fire Attack Force that camp (and the surrounding forest) was saved. All of us are therefore incredibly grateful to the CIMTROP team for this – our saviours!!!

There seems to have been a lot of flanged male activity in the area at the moment, with Drake and others chasing each other all over the place and conflicts/aggressive chases observed on a couple of occasions. While I was following Drake, a sun bear came along twice and foraged directly below his feeding tree (causing me to move away!), but the OU seemed completely unconcerned. Ella 2 purposefully (I think!) defecated on me, which made the rest of my day very pleasant! Romeo pretty much ran away from Ella 2 when she wanted to play with him one day; I have no idea why he was so reluctant to have her around, but he clearly didn’t want to play!

September 2006

This month, we had a few half days on a couple of males (Drake, Marvin – new, and the unflanged Shogun), of whom only Drake is completely comfortable with the presence of observers. On the female front, we found Teresia, before meeting up with Indah (who made up the majority of the month’s follows). After that, had a couple more half days on semi-habituated unflanged males. Not a great month by any reckoning, but a big improvement on the last couple of months!

Iwan saw Leonardo kiss squeaking using leaves, which was the first record of this from Sabangau – the OU put leaves in between his mouth and hands (both hands were used). Indah wasn’t at all happy when Feb came along on a couple of days wanting to play with Indy. She kiss squeaked at her and chased her away a couple of times, presumably because she was scared of Isabella being hurt in rough play. Indah was seen drinking from pitcher plants on a few occasions and from dug-up roots a couple of times. This is presumably related to the dry conditions in the forest and consequent heightened water stress.

Highlights: December 2005-August 2006

• I’m pretty sure that we saw the transition of Mozart (we were all fairly sure, but in any case, a large unflanged male, with a small thraotsac but no cheekpads) into a flanged male. One male OU went through a phase of coming really regularly into camp when liana kuning and liana Otto-Otto were in fruit lots near camp. This male was well habituated. A few times we came back from searching all day only to find he had turned up at camp!! Between Dec and May, this male that kept coming to camp seemed to get less unflanged and more unflanged every time we saw him, to the point where, by May, he looked pretty much fully flanged. True, there could have been many brave, habituated OUs of various stages of flangedness that liked coming to camp, but I think it’s much more likely we saw a transition. In April, we also heard a few long calls at night (when Mozart was near camp), which I think may have been him learning to long call, as he felt safer practising at night.
• More of a lowlight really, but for the last two months, we’ve had virtually no OUs. 2-4 people have been out searching almost every day, but nothing. Even people out doing pheno, resurvey, vol stuff etc. haven’t seen or heard a peep. There’ve been no long calls from in the grid either. Compare this to last Aug (and was it 2004?) when there was loads of Katiau flowers around and we were practically falling over OUs, with vols seeing them on their first day etc. I think that what’s happening is that katiau is flowering heavily elsehwhere and all our OUs have moved temporarily to take advantage of this (there’s some, but not much katiau flowers around now, which lends some support to this).

August 2006

A follow month from hell. Five half days at the time of writing (27th): three on Feb and two on Cleo (the first time we’ve seen her since December).  I think that all the OUs have moved out of the area to feed on super-abundant katiau in neighbouring areas, though I have no direct evidence to support that. A reasonable amount of fruit was found in the phenology plots, so a complete lack of food probably isn’t the reason. Cleo made a strange noise, sounding almost exactly like the start of a long call (I actually doubted whether she was a flanged male and I had just judged her size wrong when I first heard it!!). She made this noise a couple of times, along with some guttural throat rattles that I had not heard before. She also used her hand to kiss squeak.

July 2006

Despite our best efforts, this was a poor month for follows, with only a few nest-to-nests and not a great deal of half follows either. Long periods of searching to no avail. Indah and Indy came to the rescue again and saved us from having an absolutely terrible month. Indah was eventually abandoned past transect HH, a long way west for her and hasn’t been seen since. Indah makes a ‘leaf seat’ while feeding (a loose platform of leaves, not inter-woven like a nest).

June 2006

Lots of data on Indah again (full follows), plus quite a few part follows with an assortment of flanged and unflanged males.Indah is still hanging around near T1.6 and 2 eating kepumpung (caterpillar pupae). Indy is still with her and still maintaining the association, but with Indah still doing little/nothing to discourage this. Isabella is now travelling around on her own (within trees) and spending more time off Mum every day. She still clings onto her mother when travelling between trees though. Indah kiss-squeaked a lot at pigs – she passed a large scrape on a couple of occasions – possible because she is wary with her small baby (pigs have been reported to kill immature orang-utans).

May 2006

Not too many follows this month, but a lot more nest-to-nests, as weather conditions improve. Becomes possible to come back from forest with dry feet if wearing wellies. Indah and Indy were the main individuals followed, but Mozart, Feb and Franky were also around. Indah is still generally controlling the direction of travel – although Indy may sometimes go ahead and even out of earshot, she never goes too far and always returns to her mother. Indy is definitely the one keeping up the association, although Indah does little/nothing to try and discourage this/force Indy away. This must surely happen soon, as Indy approaches the time when she will become independent of her mother. Indah was not at all happy when Feb (a independent adolescent female) tried to play with Indy though and chased her away! Isabella (Indah’s baby daughter, born in November 2005) was seen playing with fruit and unsuccessfully trying to eat it, but sure she’ll keep trying! Caterpillar pupae were also eaten (this is a fairly rare behaviour, but OUs clearly love them, as they eat lots during the short periods when pupae are in abundance).

April 2006

This was not quite such a good month for follows: we had fewer follows and are still having difficulty finding and keeping animals. Plus it’s still really wet in the forest still. Beethoven is still around (and chasing us poor researchers!). Mozart, Indah, Romeo and Bengy were also around. Mozart seems to be developing rapidly into a flanged male.

March 2006

It was mostly males that were followed this month: Mozart, Beethoven and Wallace, but there were also a couple of days on Indah and Ella 2. Lots of orang-utans were found close to the river where there seems to be most fruit at the moment. Beethoven is still chasing after other males all over the place. An unflanged male was seen making an umbrella (a common behaviour) in the rain and then carrying it and putting it in its nest (uncommon!).

February 2006

This was an OK month for follows: lots of OUs found and followed, but few from nest to nest, due to bad weather conditions. Beethoven and Feb were followed the most, but Jupiter, Leony (new, no pictures unfortunately), Romeo and Shogun were also around. Beethoven was busy chasing after more males. Jupiter around too – would Beethoven be brave enough to do all this long calling and chasing if Jupiter is king, as we once thought he might be? I think not; Beethoven seems like the king to me. Feb snag rides, falling with tree and grabbing branches at the last minute. A new (?ID) adult female runs away from Beethoven.

January 2006

This was quite a good month for follows. Beethoven, Feb, Hengky, Kay, Indah, Franky, Mozart and Ella 2 were all followed. The forest is starting to get wet now. Beethoven seen chasing other males/LCs, and Hengky seen running away from another male. Although non-focal ID’s weren’t confirmed, I think Beethoven must have been chasing both of these males.

Hengky was seen washing himself in a puddle on the ground, another first for Sabangau. Feb was seen searching through more birds’ nests. She was also seen entering a nest with Mozart and an unID’d unflanged male on two occasions. Although on one occasion the observers thought they might be mating, I saw the second one myself, which was similar to how they described the first one, and I think they were just playing (an investment for the future???). Mozart seen repairing Feb’s day nest for a night nest. Feb seen entering another OU’s old nest. Feb had a rasau flower stolen from her by a male and begged for it back, but was unsuccessful.

December 2005

Beethoven was around a lot this month, as was Mozart and Feb. Indah, Cleo, Leonardo and Kay all followed too. The last follow before Christmas was on 22nd (although the OUs didn’t have a holiday, we certainly needed one after the last few months of hectic following!). Although Iwan and Yudhi did work over Christmas, they did some gibboning and litterfall and didn’t find anything when they went out looking for OUs. Indah was seen building a bunk nest/roof above her nest in the rain on 7th. This was the first time this behaviour has been observed here. Mozart is still unflanged at the moment, but is pretty big and looks like he’s developing fast.

November 2005

The enduringly lovingly Gracia was found on the 1st. She seemed to be slightly less aggressive than on past follows. She was with another, unidentified unflanged male OU and they stayed together for the duration of the follow period, which only lasted until they went out of the grid past T2.5 on the 2nd. They both seemed content with each other’s company and both sides kept up the association.

Indah, Indy and the new baby were found again on the 3rd, and at mid-day they met up with Shogun and travelled with him for the rest of the day. He wasn’t around anymore on the 4th. Indah did little of great excitement, except for eating lots of fruit (which must have been exciting for her at least!). We were quite excited too, as we managed to get a bit of a better look at the new baby and are now quite sure that it is female. Following tradition, the person that first finds the OU names it, and Santi decided on Isabelle, which is quite fitting I think. The follow ended on a dramatic note, with Zery getting stung on the head by some bees after accidentally stepping on their nest. Indah then had to be abandoned as he had to go back to camp. He was in quite a lot of pain for the rest of the day, but being the strapping lad he is recovered and was fit to work the next day.

The next OU we found was Viola on the 10th. We are still confused over her lack of infant – it is most unusual for an adult female OU not to have an infant in tow, and she is certainly adult. Possibly something happened to her infant?? She was only followed for a few hours and was lost later that day.

Feb was also found again on the 10th and straight away set about scaring gibbon Group C out of a fig tree they were feeding on so that she could feed there. Interactions between OU’s and gibbons are quite rare, but it is almost always the larger OU that comes out on top. Later on that day, she encountered the gibbons again and this time they fed on figs together for a short time before the gibbons moved off. The 11th was quite uneventful and she was then lost in the rain on the 12th.

We then went through a bit of a barren spell, with days of searching for OUs yielding nothing. There was little fruit around in the forest at this point and it is likely that many of the OUs moved into other parts of the forest in search of food. The next OU found was Feb again and Beethoven on the 18th. Unfortunately, Beethoven was lost while travelling on the ground later that day (big males often travel on the ground, and it can be very difficult to follow them when they do this, as you can’t see them and they are very quiet, quite the opposite to when they are in the trees!!). Feb did nothing of great excitement and was then lost in the rain on the 20th.

A new flanged male, Hektor, was found on the 21st. He was a little bit aggressive towards the observers, with quite a few kiss squeaks on the first day, but he settled down a lot on the second day. He long called quite a lot, but didn’t move very far. He moved nests during the night on the 22nd and couldn’t be found again.

Indah was found again on the 22nd, a day she spent mostly resting and eating leaves, before tucking up for the night at 2.30pm! She was lost on the 25th, but then found again on the 26th, when she ate a lot of epiphytes. On the 27th, she met up with an unflanged male, who we initially thought could be Romeo, as he seemed completely unconcerned by Twenti and my presence. Both OUs were followed the next day and it soon became clear that the unflanged male was not Romeo. Shortly after getting up, they went their separate ways and, once on his own, the unflanged male suddenly became very scared of the researchers and spent the day kiss squeaking and running away. He wasn’t followed the next day as he nested too far out of the grid. We still don’t know who he was. Indah was abandoned after making her nest on the 28th, as she had been followed a lot recently.

Mozart was found close to camp again on the 29th and, not wanting to break a pattern, went straight out of the grid again on the 30th, thus rounding up the month of November. The forest is now much wetter after recent rains and finding and following has become more difficult (as it is hard to see and hear OUs in the rain). But while the OUs are still around, we’ll still be going out into the forest to follow them – how else would we get the next instalment of Sabangau Orang-utan Diary to you?!

October 2005

Beethoven was found on the 29th September, and long called quite a lot and ate lots of jangkang kuning fruit. He was followed until the 2nd October, when he went out of the grid chasing another long-calling male and had to be abandoned. Mozart turned up at camp again on the 4th and, predictably, went straight out of the grid and had to be abandoned the next day.

Cleo ate lots of pisang-pisang besar fruit and was only followed until the 8th, when she went out of the grid and had to be abandoned whilst still eating at 6pm in the dark. She met up with Archimedes and they travelled together with Feb. The three of them travelled together quite peacefully until Archimedes left at mid-day on the 8th. Feb stayed with Cleo until they were both abandoned. Archimedes went straight out of the grid past T2.5 after leaving Cleo and had to be abandoned.

Cleo was found again back inside the grid on the 9th with Feb still in tow. Feb and Cleo spilt on the 10th and after feeding on figs for three hours was lost in the rain and not found again.

The highlight of the month, and in fact of the Sabangau OU research to date, was the discovery by Santi on the 12th that Indah had a new baby!! This was the first OU birth we are aware of during the lifetime of the project and everyone was very excited – Santi was beaming like a Cheshire cat!!  Unfortunately, the actual birth wasn’t witnessed, but it had only been a couple of weeks since she was last followed and so the baby had clearly been born in that time. This has now given us a great and rare opportunity to study the differences in behaviour pre- and post-birth.   At this stage, the sex of the baby was still unknown, as the baby spent all of its time clinging tightly to its mother’s side, making it impossible to get a good look at its private parts to confirm the sex.

Jupiter was found again on the 12th and, in contrast to last month, made no long calls. He was only followed for a day, as we wanted to concentrate on Indah and her new born. Indah met with a flanged male on the 13th and seemed slightly uneasy in his company until he left late in the afternoon. Indah was then lost on the 14th in very windy conditions. She was found again near T0 on the 15th and was followed until the 20th. For all of the time they were followed, the baby was still spending all its time holding on to its mother and Indy seemed to be being forced away more and more.

Shogun was found on the 22nd and was followed until the 24th, when he went out of the grid past T2.5. He spent most of his time kiss squeaking at the observers and running away. When he wasn’t busy doing this, he ate quite a lot of pisang-pisang besar, which seemed to be the food of the moment and was present in much larger crop sizes than is typically seen at other times of year. Wallace also graced us with his presence on the 22nd and proceeded to try his best to threaten and scare us! He also met up with Gracia and her infant George, and another small orang-utan, who may have been Bengy. This meeting was mostly defined by Gracia kiss squeaking at the observers. Wallace was abandoned when he went out of the grid past T2 on the 24th.

The next OU found (and lost) was the mighty Beethoven on the 26th. In this brief period, he managed to meet up with Indah for a while and scare her, and long call lots. Romeo was then found on the 27th and followed until he was abandoned past THH on the 31st. Not wanting to deviate from his peers, he also fed on lots of pisang-pisang besar (a type of fruit with very hard seeds), but was quite anti-social (only nesting close to another, unidentified OU on one night) and did nothing of any great interest.

September 2005

The last instalment of Sabangau Orang-utan Diary saw Feb and Cleo meeting up; read on to follow their exciting adventures and the latest from the rest of the orange crew.

The young female orang-utan ID problems, that have been a feature of the orang-utan research in Sabangau since the beginning, show no sign of abating – we are convinced that there are at least two, one that often hangs around near camp (Feb?) and then one that often hangs around near T1.6/2 with Cleo (Ella? who we originally thought was probably Cleo’s), makes loads of nests and spends half her time trying to annoy us. 

Anyway, whoever the small OU is, it hung around with Cleo for a few days, until Beethoven came along on the 4th and chased all the observers away. They were right down near T0 when this happened, far out of Cleo’s usual range. Feb was then found again and on the 6th went on a bit of a rampage (with two volunteers in tow!!), travelling from near T0.4, all the way up to T2 and then back again almost to T0!! None of us had ever seen an OU travel that far in a day before, the boys drank all their water by mid-day!! She wasn’t followed again the next day, as had been followed a lot recently, and no one’s legs were up to it!

The next day, Zery lucked out again and found Franky, who threatened and chased him for 1½ hours, before Zery decided he was probably happier on his own. Thomas and Otto found Beethoven that day too, then lost and found him twice, before Thomas was bitten on the head by an angry centipede and that was that for the day (and for a day or two after for Thomas too!). The flanged male theme continued the next day, with the guys finding Jupiter. He didn’t do anything very exciting apart from long-calling quite excessively (14 on one day!) and having a good lye-in (8.30am one day – would have been nice if he’d have let us know this before we left at 4am to get to the nest!). Indah was also found again that day. She ate lots and then went to bed at 2pm the first day and 1pm the next!!! She’s pregnant and I guess foetuses need lots of rest before they come out into the real world. On the 12th, there were lots of long-calls from the south, and Jupiter went rushing after the perpetrator to restore order and was abandoned way out of the grid.

On the 13th, the guys bumped into Wallace, who treated them quite nicely and made a few long-calls. He then met up with Indah, they spent an hour or so looking at each other (Indy moved off scared and then got upset with some gibbons). Wallace went straight out of the grid the next day.  Indah seems to be increasingly trying to force Indy to become more independent. This is much to Indy’s annoyance – she has been following her mother whenever she moved off (previously, it was often Indah that followed Indy when she moved off) and crying a lot when her mother pays her no attention.

Indah and Indy were followed until the 20th, when the BBC came to camp to make her a world superstar!! This was a great opportunity to raise publicity for our research and orang-utan conservation, and it was a real privilege to have them here filming the Sabangau orang-utans. Indah and Indy did not disappoint and put on an interesting show for the film crew, though most of this was shot in light to poor to be used on TV. They had a honey feast first thing (while it was still dark and the bees were still relatively inactive) from a bee’s nest they had fed on the day before and then spent an hour or two resting to recover from all the stings.  We thought that after all the excitement with the film crew, Indah was probably a bit tired and needed some rest, so as we already had lots of data on her, we let her be. This film was broadcast on BBC 2 on the 10th January 2006, as part of the BBC’s Apes in Danger series. The main focus of the film was how the oil palm industry is putting more pressure on orang-utans and driving them further towards extinction, as forests are cut down to make way for plantations.

Mozart turned up at camp again on the 20th and made his nest 10m away from one of the houses. Unfortunately, he went straight out of the grid the next day and had to be abandoned.  Feb was also found on the 21st, but left the grid on the 23rd and getting lost in the confusion created by a huge group of macaques. She was found again on the 25th and was observed eating pneumatophore roots, possibly for medicinal purposes (orang-utans have been seen sucking water from dead roots, but this root appeared to be alive). She travelled all the way from T1.6 to T0 the next day, where she met with Mozart. Mozart was also followed the next day but, in what appears to be coming a bit of an annoying pattern, went straight out of the grid and had to be abandoned. Feb met Cleo was followed until the 7th October, when Cleo became focal as Feb had already been followed for ten days.

August 2005

On the 8th, Oto found Shogun, who was only followed until the next day, when he wussed out of fighting with another OU and ran off on the ground not to be seen again.

Also on the 8th, we found a new flanged male, who did 4 long calls and was quite aggressive towards us, although he didn’t chase anyone (was new and so probably wasn’t brave enough). The next morning, there was 8 LCs from all different directions and the new kid on the block bottled it and ran off on the ground. Not top be beaten, Kirsty and Santi searched for the rest of the day and found the lovely Teresia, who proceeded to kiss squeak at them non-stop and run away until they had to abandon her as she was miles off the grid past T0.

Archimedes was found on the 10th, kiss squeaked a lot and then went way out of the grid near T1.3 later that day.

Fanser (should that be he) was found on the 10th. He was new but was not really aggressive towards us. Found Cleo on the 11th and she met up with Fanser on the 12th. They hung out together until the 13th, when they both went out of the grid past T2.75 and then went their own ways just after they went out. Seemed like Cleo was following him rather than the other way round. Both of them seemed quite happy with each other’s company. Cleo also ate lots of fruit and met up with K for a bit and they fed together and hung out for a bit without really doing anything interesting.

On the 15th Beethoven was found by Zeri by TDD. He long called 5 times that day and made a mad dash to the west and finished up out of the grid near TJ. He hardly ate at all that day, just snacking briefly on leaves and termites. He wasn’t followed again the next day as he nested too far away.

On the 18th Indah and Indy were found again and were followed until the 25th when she was abandoned near TJ. Indy cried a lot, possibly because she was wanted to suckle and her mum was having none of it. On the 19th Hengky came along and faced off with us for about half an hour. Indy kiss squeaked at him and they left the feeding tree before he moved off and followed them. He then stayed on the ground a little way from them and when they moved off, he didn’t follow. She met up with Gracia (a new OU) on the 23rd, but they weren’t very friendly with each other. Indy and George played with for each other for a bit, but Indah and Gracia didn’t have any contact or feed in the same tree etc. (possibly because Gracia was too busy getting in a huff over us). On the 20th Indah met up with Beethoven and they fed together for a bit (whilst Beethoven was not trying to threaten the boys).

Feb was found on the 19th and was followed the next day when she made her nest just outside of the grid. The cotton fell out of Twenti’s bag and so the nest couldn’t be tagged and she wasn’t followed the next day. 

On the 26th Gracia was found. She was followed for 2 days before she was lost on the other side of the railway. Before she was lost she met up with the unflanged male Mozart for a short time. He entered her feeding tree and they seemed to be touching one another (George cried), though we couldn’t get a proper view.

On the 28th we found Feb and Mozart. Feb was crying when he first came along, but then she followed him and they fed together and made their nests close together. The next day the main data was taken on Mozart. Mozart wasn’t really too interested in Feb, though he wasn’t annoyed by her presence. He wasn’t aggressive towards us either. Mozart went to Kereng to buy some cigarettes on the 30th (well, he went out of the grid at the very edge of the forest near Kereng!!), after running away from another unflanged male on the ground.

On the 31st we found Cleo and Feb, who were quite happy in each other’s company, and fed and travelled together continuously. To catch the rest of Cleo and Feb’s adventures, be sure to tune in to the next exciting edition of Sabangau Orang-utan Diary’!!!

July 2005

The 10th was my first day back in the forest after spending a year in the UK writing my PhD proposal, and saw Thomas and myself set out to Transect 1B/G to follow Shogun, an OU I had not met before. Shogun is still a fair way from being habituated and so we spent most of the day chasing after him and being kiss squeaked at. Fruit was the main food, and we also saw the beginnings of the flower glut that was to come. Finished out of the grid about 300m north of T0, so was abandoned. A nice gentle (?!) reintroduction to following OUs for me!

The next day (11th) Feb was found and was then followed until the 15th, when she was lost after a big group of pig-tailed macaques arrived – the racket that they made drowned out any sounds Feb made and she was lost in the confusion. She was entirely alone during this time.

Beethoven was found on the 15th near T1.3/C, but then went out of the grid near T2 on the 17th at about 09:30 as he was 400m+ from the boardwalk. Long called 5 times on the 16th, but not at all on the other days.

Went out searching again on the 18th and bumped into Feb again near 1A and C. On the 19th, whilst following Feb, Leonardo came along, and being as Feb had already been followed a fair bit recently, we switched to Leonardo. Unfortunately though, the next day he went out of the grid near T2 and had to be abandoned.

After the long weekend we found Beethoven on the 23rd, but he was lost at mid day. We were only orang-utan-less for half an hour though before we found Viola. She kiss squeaked quite a bit and was followed until the 27th, when she went out past FF and finished near the river.

On the 29th, we found Indah near T1.6 and C and followed her until the 6th, when we left her as there was not enough people to follow as we all went into town for the vols’ send off. She spent an inordinate amount of time resting and made her nests unusually early (about 16:00 was the latest and one even before 15:00). Worryingly, her urine was also black on the 3rd and 5th. I think this might have something to do with her pregnancy, or maybe she just got really dehydrated.

September / October 2004

The forest is extremely  dry now. No water in any of the canals. Still seeing 3-4 people entering the forest to hunt pigs and bats. One team has dog for hunting.

Following Hengky, Cleo and Feb (looks like the same one we called Ella when following Einstein). The confusion as to these two will continue until we get the genetics done. So we will just carry on trying our best to distinguish between the two. 

Cleo has been followed quite a bit during October, but we have had to habituate her all over again. Lots of kiss-squeaking and aggression towards observers for the first few days. The interesting thing is that when first found, they thought it was a male because she made a call which sounded just like a long call, which only the flanged males make; but to their surprise there was no male, just Cleo and baby Chivers. We are trying to document all calls on tape, but did not manage to get this one. However, Hengky seems to be the king of long calls at the moment (August-September) – making up to 15 long calls  each day when he was been followed. The long calls were usually followed by snag crashes (This is when the orang-utan will push over a large dead tree). During this time he would spend long periods resting after the calls, just waiting for the ladies we thought, and sure enough they did appear. Unfortunately the individuals which did appear we did not know, and they were  scared away by the observers, as they were not habituated. I think Hengky caught on to this, and when another female approached after he had made a long call, he then long called again and came straight over to the observers and tried to push a big snag in our direction, so we made a hasty retreat. This I think was his way of saying ‘get lost!’. He then tried again to push it over, but with no luck. Ego deflated, he then went after the female and travelled with her. The interesting thing is that when searching for female, he will long call and then push a snag (this creates a bigger more impressive sound, to show how strong he is), then will usually rest and wait (In this case waiting for them to approach him). Beethoven did exactly the same thing when we were following him, long calling and then just waiting for the females to approach, and they did. I have a theory that the long calls they make when telling other males they are around are different from the long calls they make when looking for the ladies, behaviour-wise. We noticed that the throat sac of Hengky after he made the long calling (looking for ladies) was inflated to a degree that he could almost float away ! but seriously, this has not been noticed before. It might just have been an oversight on our behalf or it could be him making himself look bigger for the girls, as they were always there when it was inflated. The more long calls that had been made that day, the bigger his throat sac seems to be, and persisted after the long call. Testosterone is flowing.  Long calls to inform other male he is around – these are usually made before travel and in the direction of travel. This is all speculation as no data has yet been analysed.

August 2004

Rain has stopped. Forest now drying out.

Mark my faithful assistant left this month, I now have a new assistant called Carly. Nick who was helping on the vol side of things has also joined the behaviour team. So I have great expectations for them both !

Found Cleo again, did not follow as was following Hengky. Yes, the good news is Hengky is still around, and making lots of long calls. Recovered a lot from his injury, but leg still seems to be hurting him. Henkey travelling lots on the ground, still does not seem confident in the trees.

Henkey did lots of long calls and eventually found a female (Cleo), travelled straight to her and did another long call.. Cleo looking much thinner and chivers much bigger.  Henkey did not seem that interested in her, circled her then left. Cleo was accompanied by FEB (still do not know if FEB is ELLA).

New female Willow, she has an infant the same size as Indy, who is travelling independently.

Romeo has turned up again, and as usual as his name indicates he is still after the girls. The female we saw him chasing after ran away and managed to escape. Although he managed to catch her twice and attempted to mate, she managed to get away by flying through the tree tops. He on the other hand was in hot pursuit, due to Romeo’s small size he is able to travel very fast high in the tree tops, unlike the bigger flanged males which are slower and have to travel lower down . In the distance we could hear no more noise, but to the east heading in the direction of Romeo and this female, was Leonardo – a bigger male (non-cheekpadder), approaching to find out what all the commotion was about. Unfortunately, I can not say any more as we had to abandon the follow, as we were well out of the grid, and darkness was nearly upon us.

Good news on Franky. My new assistant Carly was out with Santi following Willow, who was kiss squeaking like mad. Franky was near by and approached to see what all the fuss was about. In the confusion, with both kiss squeaking at them, and Franky approaching them aggressively, Willow was lost. So they tried to follow Franky, with the knowledge that he likes chasing people. Previously I had told Carly if approached aggressively by him, sit as small as possible, don’t look at him and eat leaves. This she did, with Franky only a few metres from her and low, kiss squeaking and shaking branches. At this point Santi backed away, but Carly did not follow, so he came back, legs shaking and very scared, he sat by her, telling her they must leave. Carly remained. Franky then left them and moved off after the female Willow. The researchers regained their composure and set off after him. No more aggressive behaviour – I think the breakthrough in the habituation of Franky. Not to talk too soon, but it is now nine months since we first found him. Birute Galdikas, you were right, some you can never habituate and others take time !  Which is Franky ? we will wait and see.

Two more new individuals found at the end of the month – a half flanged male Wallace, and a small adolescent, not sure on sex yet. Anyway lots of social interactions this month. Cleo was found again, she was with Feb and joined by Qu. Qu payed no attention to Feb who had already made her nest and had settled for the night. Qu approached Cleo who was feeding in a nearby tree to Feb. She stopped when Qu approached, using the tree Feb was in to tree swing to Cleo’s tree. Feb, just swang backwards and forwards, not minding at all. Then once Qu was in the same tree as Cleo she moved, again using Febs tree, and so did Qu as he was following after Cleo. Poor Feb was swaying all over the place in her little nest. Fed up with this she too joined the other and made a new nest near to them. Qu continued to follow Cleo the next day. No aggression between the two, Qu was even seen grooming Cleo – this is our first recording of this behaviour between two adults.

More to come on the social side; a new small individual ‘X’ was found and not habituated yet, so lots of KS. X is thought to be a male. He joined up with K, and once again lots of social interactions, grooming, playing and what might have been food sharing. The relationship between these two is not known, particularly if X is a male. Adult males and females are known to socialise – bonding if you like, but adult males and adolescent males, I am not sure about – maybe they are siblings ? Adolescent males are known to travel together and are more social than flanged males.

Indah and Indy have been found again, which I am glad about, as it has been a while since they were found. Indy has been her self, playful and being a little  naughty, throwing branches at the observers, as per usual – all in good humour !!! Indah is thought to be a little ill, she fell out of a tree one day from 10-15m high, and appears to be resting lots. Her urine has shown lots of Ketones and some proteins, which may indicate a kidney infection, we will see. The ketones indicated that she is using up her fat, and this happens when there is not enough food around. Orang-utans are very efficient at storing fat, and store it very fast when food is plentiful, however, they also use it up quickly when food is scarce. We have been a bit lax on the urine collection over the last few months, so I do not know how long ketones have been present in their urine, as most of the orang-utans tested this month have positive ketone levels.

July 04

Still raining- which is good – forest still wet.

New male found – Urigella. Lots of confusion over the big males from the assistants. Urigella was called Jupiter, and Henkey was called Beethoven. A new female also found called Teresia, who has a small baby (may be 3 months old). Did not managed to habituate her before losing her.

Franky been found on a number of occasions and still aggressive to observers, chasing them etc.. Mark did not run one day, but Thomas did, so Franky went after Thomas.

April 04

There seems to be a lot more social activity this month, which is due to the increase in food available. Both Bintangor and Kapunaga are fruiting all over the forest.  

New orang-utans found:

Picasso –  female adolescent – a little bit bigger than Feb. Quite independent.

Potret – Female – think she is the mother of Picasso.

Think female as 2 males went after her, she fled and left Picasso in the tree feeding alone. Picasso continued to feed and then moved off in a different direction. About an hour later Potret found Picasso and continued to feed with her. Once again 2 other individuals, think the same ones from before, chased her and she rain off, this time Picasso followed cautiously behind. Potret could not out run them, and made a night nest, the other did the same near by. I do not think any contact was made.

The next day, more orang-utans joined the party, the new individuals were a female with an infant the same age as Indy. They travelled and fed together. No aggression from any individual towards another. All was fine, until a big flanged male, we think I could have been Beethoven, turned up, and the party separated, and all individuals fled in different directions. One small individual, I think Potret, was chased in a circle, she was travelling high and fast in the canopy and he was low. This continued for 15 minutes round and round, until the male got tired and gave up. We (Andrea and myself) were sitting right in the middle of it all, and did fear them getting too close to us, but the chase was eventually over and the female ran off. So from following six individuals we had now lost them all, even the big male.

Qu a new individual we found when we lost Potret is an extremely aggressive individual. Lots of threatening behaviour, kiss-squeaking lots, approaching and throwing branches and pushing over snags. This lasted for most of the time we followed. Qu met up with Indah and Indy. There was no aggression from either, however, Qu was still very aggressive towards the observers (Oto and me). He spent the day following Indah and also playing with Indy. Indah did not seem to mind. They travelled and fed as a travel party. Then at about 2pm an unidentified individual, who was named Viola  (adult female with no young) arrived, and chaos broke out, lots of running about in the canopy, kiss-squeaking and lots of throwing and breaking branches from Viola, this set off Qu as well. Indah wanted no inclusion and descended to 3 meters with Indy on her back. She remained therefore about one hours while Qu and Viola ran about kiss-squeaking and throwing branches. The aggression was directed at  the observers, and only stopped when they both departed for another tree. There was physical contact between the two. Qu followed Viola when she left. I tried to follow Qu, but at this point another individual (Romeo) arrived, he must have been alerted by all the kiss squeaking. When he approached her she immediately approached us and then him, as if to chase Romeo was sure Qu was out of sight, he then approached Indah, who did not put up too much of a fight and mated her. Indah seemed to open her arms and hold him – it did not look as if it was forced, lots of grunting was been made by Indah at which point Qu would come rushing in and Romeo would make a quick departure. As for me and Oto, we were only about 3 metres away, but this did not put Romeo off.  Over the period of about three hours, Romeo mated with Indah three times. I think the first two attempts were not successful, as the last mating lasted for 15 minutes. Indy would try and fight Romeo off, but he would just push her away. This could be a reason why Indah let Romeo mate with her, because she did not want Indy to get hurt. Usually adult females with infants, which are not weaned, are not receptive and therefore will not want to mate. If they are ovulating they will usually seek out an adult flanged male.

Mid April: I went away for a break for a week, and when I came back, all three of my staff (Darsono and Sadho) had quit with only one days notice. They apparently were going to work in a plywood factory and the other Oto worked out his months notice. He had been saving to do his teaching exams. Lucky for me, he was able to help with the training of the three new assistants, one of which was Darsono’s brother Santi.

March 04

More questions – Where is Ella ?

Indah and Indy met up with another orang-utan, one we had not followed before. They meet near T0 and TE, this new individual approached Indah, and Indy went to it, there was no hostility between them, this new one even pulled Indy towards it, there was no resistance. It is not know if this new individual is male or female. It is estimated to be about 10 years old, no facial hair, just a bigger version of Indy. It showed no aggression toward the observers, Simon who was following Indah left her to follow this new individual and habituate her, but she was eventually abandoned when travelled out of the grid. Indah seemed quite protective over it, so it could be a relative, as female orang-utans have overlapping home ranges.

Indy seems to be getting a lot more aggressive toward the observers, throwing things and them and KS lots. She is also initiating travel, and running from observers. It is almost as if we are habituating Indy now!

Findings of Interest.

Using hand to KS (hand covering mouth) – most individuals.

Pinching lips – most individuals.

Making umbrellas in the rain.

Some individuals make raspberries when making night nests (Franky, Jupiter, Beethoven, Romeo, Feb, Indah).

January and February 2004

These two months have been quite exciting.

Ella has been found again, this time on her own. Over the New Year she seems to have matured greatly. Her punk hair-do is gone; it is now long and circles her face. She is bigger and kiss-squeaking frequently now, which she never did before. Cleo we had not seen since September, and all of a sudden she returned. Once Cleo was back, Ella joined her. This time Cleo showed no aggression toward Ella. We think that during September Cleo was pushing Ella out; females will do this to their previous infant once a new one comes along. In doing this she is trying to make Ella more independent. Now that Ella seems to have embarking on a more independent life style, Cleo is more ready to accept her again. They feed in the same trees and even touch each other. We now think that Ella is Cleo’s offspring.

Ella also has become more aggressive towards the observers, pushing over snags (standing dead tree-trunks) and throwing things at us. We don’t know why she has become more aggressive in the last few months. One thought is that she may have come across some loggers within the forest, who were hostile towards her; or it may just be a result of her maturing.

Beethoven has been followed a number of times in the last two months. He has been in pursuit of females, and is making lots of long calls. A new female who we have not identified yet was seen approaching Beethoven just after he made a long call. She had an older infant travelling on her back, so she may be approaching the time for courtship.  As she had not been habituated yet she took offence at our presence and became particularly aggressive towards us and departed the area shortly after this encounter. Because Beethoven was so far from camp we left him shortly after this follow, so do not know if she returned.

This month Beethoven was also seen chasing off Franky, who we were following at the time. This is the clearest sign yet that Beethoven is probably the dominant male, and that Franky almost certainly isn’t. We appear to have found our dominant! Franky, though, as a big male who makes frequent long calls, may challenge Beethoven in the future.

More good news, we have just found Indah and Indy again, as we have not seen them since the beginning of December. Indy has grown and is much more independent now, travelling most of the time on her own and feeding in different trees from her mother. She is also making frequent kiss squeaks at us. She has started making her own sleeping nests, but abandons them to sleep with her mother at night.

Now to the question of Elsa, the female we saw in September and we assumed was Ella’s mother. Elsa was recorded as having  a very distinctive sticking out belly button. Indah has the same, and Indah has a small infant Indy who at the time was travelling on her back a lot of the time. So to the question of who is Elsa, Elsa is Indah and the infant on Indah’s back must have been Indy, with Ella sneaking in and confusing us all!

December 2003

One day this month a hell of a racket was coming from the forest near to where I was searching. I ventured in and found Henkey. However, it was not the same confident, long-calling male as before.  Henkey had now sustained an injury to his right leg. He was bleeding from the knee and had broken his little toe, which was now sticking out at an angle. Due to this injury he could not use his leg and was travelling using only 3 limbs. Orang-utans usually travel quite fluidly through the canopy – which is amazing considering their large bulk. The best type of locomotion for orang-utans in disturbed peat swamp forest is tree swaying, where small trees are used like a sort of pole vault. Now with only 3 limbs to use, you could see the struggle. Branches would break and he would come crashing down. On one particular day, he spent the whole day in his nest only venturing out to feed briefly.

We don’t know how he was injured, but there are a number of possibilities:

1. A few days before we found Henkey, 12 long calls were heard – this could mean that there may have been a fight between two males, and Henkey was injured.

2. That same day we also hear a number of gun shots, so he may have been injured by a shot.

3. Or, he may have fallen and sustained his injury that way.

We continued to follow Henkey through December, and it looked like his leg was slowly improving. However, travel was proving difficult, and so was making nests. On one occasion he had to abandon his first attempt, due to the inability to make it. He would now come lower to the ground and make nests on fallen trees. We eventually lost Henkey when another male turned up, and he made a hasty retreat on the ground. This tactic of escaping on the ground from other individuals is known to be quite common in Tanjung Puting National Park. We think his escaping on the ground was probably due to his injury, as travelling through the canopy was slow and awkward for him. Once on the ground he came right for us, not aggressively but we still retreated quickly to keep out of his way. In all the thick undergrowth we lost him, it is amazing how quiet orangutans can be when they want to!

Felling vulnerable due to his injury Henkey would not want to stick around the area, where there other big males, including the dominant male. Adult flanged males are predominantly solitary, except when courting and are therefore hostile to other males. During the whole time of the follow, Henkey did not make any long calls, where as previously he had.

How Henkey sustained his injuries we will never know, but we have now ruled him out as the dominant male. This however does not mean he was not the dominant before December, or that he may never be the dominant in the future. We do however hope that Henkey will return to fight another day.

A new orang-utan ‘K’ was found, this orang-utan remains as ‘K’ as we still do not know the sex, but think it may be female, despite the huge ginger moustache! K was followed for only 2 days and then lost, due to the camp-dogs following us early one morning and the follow having to be abandoned. The dogs returned with the researchers and ‘K’ has not been seen since. If ‘K’ is female we hope to find her again, as females have stable home ranges.

Beethoven turned up again for the first time since September. Habituation with him took no time at all; we were able to follow him from day one, with no kiss squeaks at all. His large size and frequent long calls made us wonder whether HE may be the dominant male. He travels vast distances and at a fair speed in search of something, probably females.

With Henkey out of the picture as dominant, it was now between Franky and Beethoven. Which one is king?

November 2003

November was a good month for following as our staff has become trained up and we could put 3 teams out, thus able to cover a bigger area. During this month we followed 7 different orang-utans.

Booming long calls were heard from a male we named Franky. He was a large male, extremely big and slow-moving through the canopy. Habituation was proving difficult, however.. He wanted nothing of these strange people following him around all day, and was eventually lost on the 4th day. We thought he may be the areas dominant male.

Jupiter, another big flanged male was found this month, but he did not make any long calls. He also seemed a lot older than the others males we had seen. We think he may have been a wanderer just passing through. We managed to follow him for nearly 10 days and then lost him in the rain. We were sitting right under the tree where he was resting from the rain, but somehow, this enormous male was able to escape without us even noticing. During the rain is the time when we frequently lose orang-utans. The noise of the rain all around makes if difficult to locate where they are within the canopy and visibility is also obscured. Jupiter was the first orang-utan we observed making an umbrella out of leaves to shelter from the rain.

Henkey appeared at the same time as Franky, and was also a flanged male apparently in his prime, making lots of long calls. He is the third candidate for dominant male, together with Beethoven and Franky!

We spent a lot of time with Indah and Indy. Indah is an older mature female with an infant, Indy, around the age of 4-5 years old. Indy still travels a lot on the back of her mother. She does however, venture off on her own when her mother gets to a big feeding tree. Once Indah is ready to leave she will always wait for Indy, allowing Indy to use her body to cross gaps. Indah has also taken Indy to feeding trees, where she waits until Indy has finished before moving on. The mother-infant bond is very strong at this age and Indy still has lots to learn. The inter-birth interval for orang-utans is 7-8 years.

On a number of occasions, when following Indah, she was followed by an unflanged male, possibly wanting to mate with her. When being harassed she would usually try and hide. However, on one occasion the male rushed in from nowhere and mated with her, she did not have a chance to get away. This behaviour has been considered to be rape, as females will very rarely choose to mate with an unflanged male, preferring the dominant flanged male instead. Rape in orang-utans is common, particularly by unflanged males and non-dominant flanged males in Borneo. Females will try and resist by running away and hiding, as Indah did. Whether Indah is ready to conceive or not is not known, as this type of behaviour by unflanged males is common. If she ready, one would expect her to seek out the dominant male. Female orang-utans show no visible sign of when they are able to conceive, unlike female chimpanzees. So males have to be vigilant and check regularly on the females. When the female chooses a mate the two will court for a number of days, with the male protecting her from other males which may want to mate. It is only after she becomes pregnant that the female will develop swelling of the vulva, usually a few weeks after conception. We did notice that Indah had what looked like a swelling, so we are anxious to see what develops in 9 months time.

September and October 2003

Chopin, an adolescent female around 7 or 8 years old, was given her name because it was thought she was a male when first found, and it begins with the letter ‘C’ because we assumed she was the offspring of Cleo as she was frequently seen feeding in the same tree as Cleo. When females have a new baby the older one will usually be chased away, but still visit and travel with their mother frequently.

Chopin was no problem to follow, showing no aggression towards the observers. She would frequently feed in the same trees as Cleo and on a number of occasions with Darwin, an unflanged adult male. It is quite common for unflanged males and adolescent females to co-feed together. It is thought that, in this way, the male is making himself known to her, ready for the time when she is ready to mate which will not be until around the age of 15 years old.

Darwin, being an unflanged adult male, will travel long distances looking for areas where he will eventually set up his home range. As a consequence of this he left the grid only a few days after finding him. As for Chopin we were able to follow her for a few days. Then one day when feeding, Cleo turned up, and what looked like another female and infant. In all the confusion we lost Chopin, as Chopin and this new infant disappeared off playing, not to come back. However, we managed to find her the next day when she nested near to Cleo. Not only did she nest near, but so did the new infant orang-utan. It was this infant that we had seen the previous day travelling on what we assumed to be a new female. This new female we called Elsa, and the infant Ella. We predicted Ella’s age to be around 7-8 years old.

The next morning when we arrived at the nest all three orang-utans got up at the same time, and in all the confusion I ended up following Ella and not Chopin. Ella showed no aggression towards me, in fact she was more intrigued and interested than scared. She was still small and had the white facial marking round the eyes and mouth, as all infants do. She also had a very distinct punk hair-do which most orang-utans have when they are young. However, she was not totally independent. She kept following Cleo around for the fist few weeks we followed her. Cleo on the other hand was not happy, and kept chasing her away. This poor little thing was getting quite distressed and crying lots. What puzzled us was why she was following Cleo and not the female we thought was her mother. Is Cleo her mother, and if not, what has happened to her mother Elsa and where has she gone? If Cleo is her mother why is she being so aggressive towards Ella, and who is Chopin’s mother, if Ella is after all Cleo’s daughter? It was all getting rather confusing?

So September started very productively, if a little confusingly! but ended with us losing Chopin who has not been seen since, the departure of Darwin out of the grid, and still we had not see this mysterious Elsa. Does Elsa really exist? We were sure we saw another female that day!

August 2003

This was the first month of habituation work and my assistant and I were both new at this. Although I had been to other research sites to gain training, this was still going to be very difficult. On our first day out looking I came across Beethoven, a large flanged-male, he was an orang-utan we had followed last year for one day. All our orang-utans are named in order of the alphabet, and after great scientists or composers (with the odd exception). Aristotle was the first; we found him in September 2002 when cutting the grid and followed him for one day. So our adventure was now only just starting. Beethoven I found due to his long call, which was only metres away from where I was. I radioed my assistant, but by the time he arrived there was a great commotion, lots of kiss-squeaking (distress calls) and movement within the trees, Beethoven had been following a female, and when my assistant turned up, all hell broke loose. Beethoven ignored us and was only interested in the female, she on the other hand was not interested in him, and was making a break for it; so in all the commotion we ended up following the female, who we have named Cleopatra. She spent the whole day kiss squeaking at us and running away, it is important when habituating to keep up with them, but at the same time not to scare them, keep quiet and be submissive. If they get aggressive sit low, don’t look directly at them, and as all primatologists will tell you, pretend to be like them, eat leaves, this way they don’t see you as a threat. So that is what we did, and what we continued to do whenever we met a new orang-utan. We stayed with Cleopatra all day until she made her night bed, or nest. Orang-utans make a new nest every night, near to their last feeding tree. Once we had left her for the night, we headed back to camp to write up our data and chat about our first follow. Remember we were both learning on the job. So once back at camp when writing up the description of this new individual, Amat my assistant told me had had seen a big growth on her side. I told him I thought I had seen a baby, and heard crying, but he was adamant that it was some sort of growth. Anyway, the next morning we awoke at 3.30am to get to the nest for 4.30am, as orang-utans are early risers. Once near to the nest we settled down, it was still dark and started to rain. 4.45am Cleo was up and approached us aggressively, kiss squeaking and throwing things, then she took off. In pursuit of her we managed to keep up, and sure enough, once it was light, there attached to her stomach was a tiny little baby. The baby has since been identified as a boy and named Chivers. We predicted by his age to be around 2 months old. Six days of following and Cleo was eventually habituated. We continued to follow Cleo while she was in the grid, but she would make frequent expeditions out, and when this happens we leave the orang-utan to find another.