Primate Behaviour | GVI Kenya

Inside The Mind Of A Colobus

Category: Coastal Forest, Colobus, Primate Research, Shimoni Forest | Date: Oct 16 2009 | By: gvikenya

Have you ever asked yourself what you would do with your day if you were a colobus monkey? Perhaps not, but down here in Shimoni east forest, we are rather curious…

GVI has been conducting primate behaviour surveys on the colobus monkeys for about two and a half years now. It has been a constant effort, but unfortunately we have never dedicated as much time and energy into it as we would have liked. This is due to the fact that our forest research programme has many parts to it, with an array of different surveys that all require our attention.

We have been privileged recently though, by the presence of a masters student from Manchester Metropolitan University who has come out to do his thesis on colobus behaviour in Shimoni forest!

Gareth has been with us for over ten weeks now, and still has approximately five weeks to go. He has been stomping through the forest during every waking hour in search of our beloved colobus, with the hope of quietly observing and recording their behaviours.

The main outputs one wants from behavioural surveys are time budgets. These are simple breakdowns of what the colobus actually spend their time doing (normally as a percentage of total time). So for example you could observe that during the early hours of the morning, an adult male may spend 60% of his time feeding, whereas during mid day, this may be replaced by resting (say for perhaps 85% of the time). Whilst one is recording states (which are longer durations e.g. feeding and resting), one is also recording events, which are of a shorter duration, or “instant” events such as urination, or scratching.

You may be asking yourself why we would be interested in these details of a monkeys life. Well, apart from being amazing to watch (they are scarily human-like!), these observations can tell us much about the wellbeing of the population, the impact of environmental pressures, the effects of human presence / absence, and the impact that human disturbance is having on different populations.

For example if you were to observe a troop that reside deep in the forest well away from human presence, and then compare those results to a troop that is near recent destruction, you may observe some serious differences. The troop deep in the forest may spend more time feeding in the morning and evening, and resting during the middle of the day – what they should be doing. The troop closer to human disturbance may spend more time alert, or travelling. This reduces the time they can spend on activities such as feeding, or socially important behaviours like grooming. You do not need to be a genius to guess that this will be likely to have implications for the health of the individuals and the troop as a whole.

Observing colobus in their natural habitat

So we are very happy to have Gareth here with us, and are extremely excited to see his results. They may well reveal some distressing facts, which I have no doubt we will be able to link to the increasing destruction of the forest. But the first step is collecting this data, and analysing the results. Once we have firm conclusions, the next question will be “why?” and the next step – how do we stop it.

Tags: , adult male, alert, angolan black and white colobus, behavioural survey, distressing facts, energy, events, feeding, firm conclusions, human disturbance, human presence, instant event, Manchester Metropolitan University, observations, percentage total time, population, primate behaviour, resting, results, scratching, Shimoni east forest, social activity, states, surveys, time, time budgets, urination

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Identifying the ‘Angola’ Troop

Category: Charcoal Burning, Coastal Forest, Colobus, Logging, Primate Research, Shimoni Forest | Date: Mar 26 2009 | By: gvikenya

Hello again everyone,

Today I’m going to write the first of what I hope will be an ongoing story about a particular troop of Colobus that inhabit Shimoni Forest (east). It’s a troop that we at GVI are beginning to know quite well, and are becoming rather fond of.

One member of the Angola troop

There is an area of forest, where our north / south spine runs through our third transect. The area is made up mainly of a fairly large clearing, which is surrounded on two sides by tall, mature forest. To the west of the clearing (the negative sections of our transect) the forest becomes dense with lots of thickets and low canopy, whereas to the east the clearing continues for a fair distance.

We’d always noticed there were a high number of Colobus sightings in and around that area, but because of the distances between the sightings (often up to 400 metres) it was assumed they were different troops. But recently, we have been attempting to conduct behaviour surveys in the late afternoon and early evening (the times in which our data set is falling behind in).

What we’ve noticed is that all the smaller groups we’d been seeing scattered around during the day, are actually subgroups of a much larger troop that come together in the early evening, and presumably sleep together as a large group. Colobus troops are known to do this; sleep together in larger groups, and then separate during the day to feed in smaller subgroups.

We’ve named the troop the ‘Angola’ troop. So far, we have conducted 4 hours and 10 minutes worth of behaviour surveys on different individuals in the Angola troop, but still haven’t got a complete set of demographics. The largest count we have is 14 individuals, with 3 males, 2 females, 1 sub-adult and 1 infant. I have no doubt there are others hiding away in the canopy that we haven’t seen, and that our total count isn’t spot on yet, but I intend on making it a goal in the coming weeks to try and identify every individual in the troop and successfully age and sex all of them.

This troop is becoming special to us, firstly because of the hours we’ve spent quietly observing them in the canopy , and secondly because the spot they inhabit is a man-made clearing, and illegal logging and charcoal burning continues to plague the entire area. All it would take would be for a few of the larger, key trees to be felled, and that entire troop would be displaced.

I will continue to keep you all updated on the Angola troop, and we will hopefully have a much more detailed picture of all the individuals for you all soon.

Take care, and I shall be back soon
Matt

Tags: Angola troop, angolan black and white colobus, Charcoal Burning, Logging, man-made clearing, primate behaviour, troop demographics

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Rodents and Reptiles

Category: Reptiles, Rodents | Date: Mar 09 2009 | By: gvikenya

Today’s blog has been written by Lorrayne Gaymer, an expedition member with GVI in Kenya. She is 27, from England, and has written about today’s highlights!

Today our team was in Shimoni east forest, attempting to finish the canopy surveys on transect 3. Firstly we checked the small mammal traps and found not to our surprise, Mrs Scarface (resident giant pouched rat), again! Seeing as we already have her measurements, we simply took some photos and let her go on her way.

Mrs. Scarface

We then managed to carry out over 30 minutes of primate behaviour on a troop of colobus, and finished all of the canopy cover surveys on transect 3 - a good feeling! After a nice lunch break looking out over the eastern peninsular, it was day over. The most exciting part of the day however, came on our way home when we were trudging back down the North-South spine, and our forest officer got the fright of his life as a very large forest cobra (over 1.5 metres) shot out of the bush right by his foot! It headed into the shrubs to our left, before crossing the path about 4 metres in front of us, allowing for an excellent view. It was SO long, really fat and lightning fast. Unfortunately we didn’t get enough time to wip our cameras out, so no photos. But to be honest, none of us really wanted to get that close for any length of time anyway! Still, an awesome and extremely exciting sighting!