Written by: Kirsty-Marie Moran

Personalities come in all shapes and forms, contributing to what makes you different from another person. It is also an intriguing aspect of ourselves that we share with our primate cousins. We can ask each other if we are well but with animals, this is not so easy. It is each individual primate personality that could be the key to understanding how primates feel and because we are unable to ask how they feel, we can only observe and record what we see. 

There are several ways in which researchers have attempted to answer questions on how primates feel such as taking blood samples, measuring hormones, or sitting observing behaviours.

However, in a recent study at the National Institutes of Health, Georgia State University, the researchers asked for the help of the keepers – after all, many of them have spent years with these animals. Who would know the personalities of the primates better?

Using a questionnaire based on studies of people’s happiness it has been possible to assess happiness in nonhuman primates. With many studies suggesting the results are similar to that of humans. In humans, happiness and welfare are directly linked and the study at Living Links attempted to assess welfare and subjective well-being (SWB) in brown capuchins. In doing this they aimed to determine if happiness and welfare are directly relatable in capuchins.

It was found (between 10 keepers and over 200 ratings completed), that there was a high agreement on the capuchins welfare. Finding no difference between SWB and welfare ratings, which suggests that like humans SWB and welfare are linked. Also, any low ratings of SWB and welfare ratings were found to be associated with the display of stereotypic behaviours (i.e. self-grooming), indicated that a questionnaire which took on average 3minutes could be a quick and reliable form of studying welfare.

This may change the way welfare is studied in the future. With findings such as these, it may be worthwhile incorporating SWB and welfare related questionnaires into any welfare related research in the future. Especially when you are lucky to have keepers who have spent considerably longer with these animals than the researcher (in most cases) has.

Reference:

Robinson, L. M., Waran, N. K., Leach, M. C., Morton, F. B., Paukner, A., Lonsdorf, E., Weiss, A. (2016). Happiness is positive welfare in brown capuchins (Sapajus apella). Applied Animal Behaviour Science, 181, 145-151. doi:10.1016/j.applanim.2016.05.029

Written by Kirsty-Marie Moran and Zita Polgár

Ever wondered if the animals at the zoo notice your presence? And if they do, if they mind you peering in on them?

These are very important welfare questions with many zoos attempting to answer them, including our very own here at Living Links Research Centre situated within Edinburgh Zoo. A recently published paper in the American Journal of Primatology details the results of a study examining the ‘individual differences in zoo-housed squirrel monkeys’ reactions to visitors, research participation, and personality ratings’. The study tackles the important question on whether monkeys with different personalities react differently to visitors, as well as how the size of the visiting groups influences their responses. Understanding individual differences is important because it can improve the animals welfare by catering to each individual’s needs.

During the study, the researchers recorded how long the monkeys spent by the observation window when there were small groups of visitors, large groups or no visitors. They found that the monkeys spent more time up at the window when there were large groups of visitors than when there were small groups or no visitors at the observation window. Specifically, the researchers found personality differences between the monkeys. Those who scored higher on playfulness and scored lower on cautiousness, depression and solitude were more likely to be at the window when there were visitors there.

These results suggest that zoo visitors do not have a negative impact on the squirrel monkeys but rather have a positive impact. Zoo visitors appear to be a form of enrichment, especially in those monkeys with social personalities.

The researchers speculate that the squirrel monkeys at the centre have developed this response due to a number of factors, namely that they are provided with a variety of enrichment opportunities. They frequently have positive interactions with a variety of humans through voluntary research studies and they have the option to choose from five different enclosure areas with different levels of exposure to zoo visitors.

Reference

Polgár, Z., Wood, L., & Haskell, M. J. (2016). Individual differences in zoo-housed squirrel monkeys’ (Saimiri sciureus) reactions to visitors, research participation, and personality ratings. American Journal of Primatology. doi:10.1002/ajp.22639

Written by Sophia Daoudi

Walking through Living Links you may have either seen someone industriously walking around with a clipboard and binoculars or in one of the monkey interview rooms dressed up in a boiler suit. These are the researchers at Living Links. Researchers upstairs will usually be observational researchers and downstairs, experimental researchers, studying the monkeys cognitive abilities (e.g. how good is their memory), prosocial behaviour (are they able to share) or their ability to use tools.

All research is approved by RZSS Edinburgh Zoo and Scottish Primate Research Group. The current Living Links team include, Donald Gow- Animal Research and Team Leader, Dr. Lara Wood- Research Coordinator, and Prof Andrew Whiten- Scientific Director. A lot of time and effort goes into the approval process, so it’s really important to do thorough background reading and know your subject area well. A successful applicant then goes through all the necessary induction and training at Living Links, receives a research badge and start date and finally it feels official.

Now comes the tricky part, it is essential that we know who is who. I remember the first time that I studied the capuchins and squirrel monkeys back in 2009, the groups were smaller then, but even so I thought “how on earth am I going to learn all of these monkeys?”

Initially they all looked the same and I would spend hours on the observation deck looking at them.  The more I watched them, the more I realised that they did, indeed, look different and have their own individual personalities. Looking back it now seems silly to think that they all looked the same. For instance, Junon (one of the adult female capuchins from the East group) has a white outline of fur around her face, she is quite gentle and moves cautiously.

Often the easiest individuals to identify in each group, for both species, are the alpha males, as they are usually the largest. Nowadays, there are around 66 squirrel and capuchin monkeys with babies being born throughout the year. Thankfully, the squirrel monkey each have an individually recognisable tag, but you still need to learn which colour represents which individual before you have any chance of passing the id test.

Then the fun begins, and even though there can be frustrations, such as the monkey you are watching disappears half way through the study period or you note something down and when you look back you can no longer locate them, getting to observe the monkeys in their day-to-day lives is such as wonderful experience and there is never a dull moment.

So if you are thinking of sending in a research proposal, hopefully, now you’ll have a bit more of an idea of what goes on and remember as a researcher you need to be flexible and allow enough time to collect all of your data, this way if/when, you have a “bad” day, you are less likely to panic with looming deadlines. Getting to observe the monkeys in their day-to-day lives was such a wonderful experience and there was never a dull moment. I wish I could do it all again. Now I have the joys of analysis to turn to but I’ll save that for a whole other blog.