Friday, June 14, 2013


Well today we finally got to do a playback! Hooray! Julie said it was the first playback experiment done on these gibbons in 25 years! Apparently, the third time really is a charm. We tried the playback with W Tuesday, and lost the gibbons after a very long inter-group meeting (W pretty much has an inter-group meeting every day, apparently they like telling their neighbors to get off their lawn). Wednesday it rained so that doesn't count as an attempt. Thursday they spent the whole day all the way on the opposite side of their territory from where we set the loudspeaker for the playback. Today, was just right, finally.

A little side note about the playback experiment:
I don't think I've explained it before. This experiment is the reason for all the rope setting. So, we have set ropes between territories so we can hoist up a loud speaker very high for the playbacks. The higher the better so that it can be heard from very far. So, since we did W today I will explain using them. We set up a loudspeaker in the S territory which borders W. It cannot be in the overlap of the territories or else W could go all the way to the speaker when they hear it, which would be bad because they need to be tricked into thinking this is a real situation, not a weird human machine making noise. We orient the speaker toward the W territory, and when W is close enough to hear (about 200 or less meters) we can start the playback. This is why it is so hard, because the gibbon territories can be like 400x500meters, so its hard to ensure they are in the right place at the right time. We want to see how gibbons react when their neighbors sing a predator song (stimuli recorded from a previous encounter with the fake leopard model). So we will do three tests per group, the predator song, a regular duet, and a control (probably a bird song) and see how the gibbon's reaction differs. So we play S's predator song to W and see what W does, and if W responds with their own song, we record that. If W displays behavior like rushing toward the song, scanning the ground, increased vigilance or cautious behavior like carrying the baby more or even just increased grooming or decreased distance between group members (grooming is a way for primates to de-stress), this may indicate that they understand the meaning of the neighboring group's predator song. That is the important part, because Julie is studying communication between gibbons in the broader context of understanding the evolution of communication and eventually language in the primate lineage. So, voila! Hopefully that makes enough sense.

So, the day didn't start out so lucky. Julie and I both slept through our alarms. At 5:30, we were supposed to leave at 5:45, I jumped up out of bed. I ran to the bathroom and peed and then I realized wait, Julie's light is off, shes not up either? Well at least it took the pressure off me. I knocked several times until she woke up and we both rushed to get ready. So we left late. When we got to where our rope was hung, Julie and Yun (our ranger assistant who lays in a hammock all day until we tell him to press play) hoisted the speaker into the tree and I set off to find W because we heard a male singing in that general direction. I found the singer, and as I had suspected based on the location of the sound, it was an inter-group meeting (IGM) between NOS and W. Wotan and the male of NOS chased each other a little. At one point, while the secondary NOS male had Wotan distracted, the primary NOS male approached Sari (W female) and William had to chase him off. William as I've mentioned before is the son of Wotan, but not of Sari, so he has no reason to disperse, and is in all practical purposes a secondary male. However, before William chased him away, while he was approaching, the NOS male was kind enough to drop a huge load of watery shit right above me. I jumped out of the way just in time and only my bag and the microphone got splattered. Usually when the gibbons go to the bathroom they start to pee, then poop afterward (solidly). So you have a nice warning, you see the stream of pee, which you can usually dodge and if not its not that gross, and then you have a nice warning and have already moved before the poo bomb drops. In the case of diarrhea, apparently this system breaks down and you barely know whats coming until its splattered all over the ground, especially on a day after it has rained and the splatters hitting the leaves on the way down just sound like rain drops. Anyway, sorry for the gross detail, but almost being shit on was a pretty big part of my morning.

When the IGM was finally over the gibbons were in a great place for the playback, so we walkie-talkied Yun and told him to press play. Well, he was taking a bathroom break, great. So we missed our first chance. About 10 or so minutes later the gibbons had moved really close to the river, and therefore really close to the speaker which was just on the other side. So we decided, now or never. We started the playback. As soon as the song could be heard the gibbons looked straight in that direction and Wotan immediately took off toward the sound. Sari (and William) hung around for a minute but followed shortly after. I was following Sari and doing scans on her while Julie followed Wotan. We are just taking data on the mating pair, but William displayed basically the same behaviors throughout the playback as Wotan did, besides his initial reluctance to rush toward the speaker. Conveniently, they spent most of the two hour scan in the trees right at the edge of the river, allowing Julie and I to stand on the bridge to watch them. They were really high in the trees though, so looking up at the bright sky for that long was a struggle. Every 5 minutes for two hours we collected data on their position (sit, lay, hang, move in or between trees), their behavior (scanning, moving, resting, grooming, etc.) their height in the tree, the distance between the male and female, their gazes (looking at speaker, ground, sky etc), whether the baby was on or off mom, and we recorded every move on our GPS. It was intense, but successful! They spent a lot of time scanning, looking at the ground, toward the speaker, trying to find the S gibbons in the canopy to the left of the speaker. They also groomed, but still scanned while doing so. They didn't respond with their own disturbed song, but in fact the N group nearby did, which was cool! So after the two hour scan was over, we triumphantly headed back home, and it was only 10:30. A successful day in the field and done before 11am!

Yesterday, although a complete bust for the playback, was also a cool day. I saw a bunch of different wildlife! We saw a huge water monitor lizard out of the water, unfortunately it ran so fast I didn't get a picture. They look really goofy when they run though. We saw a bunch of macaques. We were completely surrounded at one point, and momentarily lost the gibbons because of their racket. Macaques are cool though because they actually hang out on the ground some of the time, and they live in much bigger groups, so there is usually more social stuff going on (which is what I'm more interested in than vocalizations). So I got to see a lot of play fighting and chasing. We also came across a teeny green pit viper. Julie stood next to it for about 10 minutes and didn't notice it. It wasn't until she started walking away and I was following her that I saw it moving away quietly. It froze once it knew we had noticed it, which allowed us ample picture taking opportunities. The pit vipers really aren't aggressive at all, they mostly just want to blend in and not be noticed. It was very pretty, it almost had a light blue sheen on its sides, different from the last one I saw. To top it off, at night a porcupine was hanging out in front of the porch, and I finally had the opportunity to get a photo!

Pig tailed macaque-found while trying to locate gibbons. Darn.
 The pond on W is starting to fill up after Wednesday's rain. Rainy season!
It used to be just mud.
 Cool fungus!
 Tiny pit viper. Less than an inch in diameter.

 Macaques are always moving, so it is hard to get non-blurry pictures.

 Malayan porcupine!

Woke up late this morning, but still had to take time to photograph this pretty sunrise outside my window!

1 comment:

  1. I love the picture your words paint of the diarrhea dump. I know someday you will have no problem if a kid comes in your bedroom and barfs on the back of your neck while you are sleeping...all in a day's work.