Written by Dr Emma McEwen

In many of the experiments at Living Links we use physical apparatuses that the monkeys can interact with, like different puzzle boxes, enrichment containers, dispenser shoots or objects for them to explore. When we design these new apparatuses, there are lots of different considerations we have to be aware of, and its often a collaborative effort between the researcher, the keeper team, and our Psychology & Neuroscience workshop to come up with the best solutions!

Our primary concern is always the safety of the monkeys, and of the experimenters. We always have to consider that a material is safe for the monkeys to touch in a way that they can’t get hurt, is non-toxic and easily cleaned so that it’s safe for their food rewards to touch, and something they can’t pull into their enclosure and do damage with.

Secondly, it has to be durable – capuchin monkeys can be stronger that you might think! We always have to consider the durability of the materials we use, making sure they can’t be easily torn or snapped, and that the monkeys can’t knock them off the experimenter’s table.

It also has to be enjoyable – we always want our research sessions to be enjoyable experiences and only positively reinforce behaviour. This includes only using materials and apparatuses that the capuchins enjoy interacting with. Sometimes, it can be difficult to predict whether they will enjoy touching certain materials. For this reason, we sometimes run some taster sessions, called pilot sessions, to offer the monkeys a chance to interact with a material or part of an apparatus before we build the finished product.

For example, myself and my collaborator Andreea Miscov are currently testing two types of material to be used as potential ‘flaps’ for a grid box the monkeys will need to search for food rewards in, as part of a memory experiment. One is a silicone material and the other a harder plastic material. There are often individual differences between monkeys, and while some of the monkeys have no problem touching the silicone material, others have not wanted to! On the other hand the plastic material seems preferred from pilot testing so far. It can be important that there are no major differences between how the monkeys interact with apparatus, especially with experiments looking at time measures (a monkey less keen to touch an area of the apparatus will take longer to get their food reward!).

Video example showing durability test, prototype flap box and piloting with the monkeys!

Last but not least, it must be practical – for the designs of our experiments, we need our apparatuses to function in particular ways such as hiding food, sliding things into other things, moving in certain ways, or having certain weights. It can sometimes take us lots of time and trips to hardware shops to browse different materials and find the one that functions or moves in the exact way we’ve dreamed of when designing the experiment!

It can be very challenging to find something that fits all these criteria, but it’s a fun problem to solve!

Written by Kenna Valles, Keeper, RZSS Edinburgh Zoo

Training in zoos provides several benefits to the animals and keepers. Training helps to keep animals both physically and mentally stimulated, while building a positive relationship between the keepers and animals, increasing the trust and communication between the two and encouraging animals to voluntarily participate in veterinary and husbandry procedures. This both builds the animal’s confidence and reduces their stress levels during these necessary events.

Just like for your pets at home, veterinary procedures in particular can be very stressful for monkeys; they often have to be separated from their group in a smaller area of the enclosure, sometimes physically restrained and handled by the keepers, without an understanding of why. However, to keep our animals healthy, these procedures are necessary to carry out regularly. Specifically training animals for veterinary purposes decreases an animal’s fear towards these procedures, allowing them to cooperate in their veterinary care and associate the procedure with a positive outcome by giving them a reward for participating.

The training performed at Living Links by keepers uses exclusively positive reinforcement techniques. This means that the training is voluntary to participate in and the monkeys are given a valuable reward, such as a food item, for performing a desired behaviour, without any punishment for not performing a behaviour. It is also perfectly acceptable for an animal to choose not to engage in training and their daily routine will continue as normal. Our research activities followed a similar training strategy, with the monkeys developing over the years a strong positive association with our research cubicles, the fun cognitively enriching games, and very tasty food rewards! Monkeys voluntarily come into the cubicles to take part as they find the experience so positively rewarding, and it’s this that keeps them returning each day for research.

The keepers have been training the monkeys to have this positive association with various veterinary procedures, such as voluntarily sitting on a weighing scale to check body weight (one important indicator of overall health) and entering an area of their enclosure called the ‘holding area’ which is used for veterinary checks and procedures.

To encourage the monkeys to start coming into the holding area and build a positive association with it, keepers rewarded each monkey for coming in by giving them a raisin, a highly valued food reward. When the training first started, the “West” monkeys were very nervous coming into the holding area; only around eight monkeys would come in for a raisin and they would then immediately run back out again. However over several training sessions, the monkeys started to become more confident and trusting of coming into the holding area and soon all 16 “West” monkeys were coming in for raisins! They also became more comfortable staying in the holding area for longer periods of time and now most monkeys will stay there eating for several minutes before leaving.

Prior to this training, when the monkeys were closed in the holding area for procedures, they would be visibly stressed and huddle in a large group in a corner. During the annual vaccinations a year ago, only one ‘West’ squirrel monkeys voluntarily entered the holding area, but this year, after all the hard work with training, all 16 monkeys chose to come in by themselves! In addition to this they were not huddled together and instead were wandering around the holding area and continued to come to the keepers for raisins, suggesting they were significantly more comfortable being in the area than previous years. This is a really great success for both keeper and monkeys!

The “East” squirrel monkey group have also been participating in the same training but have a bit more work to do before they reach the same comfort level as the ‘West’ group, but the keepers are confident they will get there! It is still stressful for the monkeys when the actual procedures are carried out (i.e. injections, being weighed) but Kenna and the keeping team hope to work on training them for these procedures as well, and hopefully with enough training, the monkeys (both our squirrel monkeys and our capuchin monkeys) will eventually be comfortable participating in any veterinary procedure.

Written by: Wilson Chen

Hello, and welcome to the Living Links Blog! My name is Wilson, I am a second-year psychology student at the University of St Andrews. I am currently working in a public engagement with research internship at Living Links. I was interested in an internship at Living Links because I wanted to learn more about the role of monkeys in the study of behaviour and cognition. Moreover, I believe that bridging the gap between psychology research at Living Links and the visitors at Edinburgh Zoo is a meaningful endeavour that can promote and educate the public about psychology as a scientific subject.

Starting a new internship in a zoo can be both exciting and nerve-wracking. I may have been looking forward to this opportunity for a long time, but it can be hard to know what to expect when you’re stepping into a new environment with new people and animals. In this blog post, I will talk about my first impression of the centre and share some of my experiences talking to visitors during my first weekend as an intern.

            Originally, I thought the first thing I was likely to notice was the smell. The smell of monkey enclosures can be quite striking, as primates have strong body odour and produce a lot of waste. However, I was pleasantly surprised at how everything is clean and tidy at Living Links. The environment on the main platform (which is where I spend most of my time working) is fantastic. I can get a great view of both the east wing and the west wing enclosures. It can get quite chilly sometimes, especially when the wind picks up, but I am sure the weather will be much more pleasant when spring comes around.

            Whether it’s to see the exotic animals or to learn about wildlife conservation efforts, visitors often come with their own expectations and interests, and it is very apparent that most visitors are very engaged with the experience Living Links has to offer. When I approached visitors about doing a visitor feedback survey, many visitors reacted positively. To be completely honest, I thought I was going to get shut down most of the time, but I was happy to be proven wrong. Visitors of all ages can be seen at Living Links, and we see a lot of families. For the children coming with their parents, this could well be their first time learning about scientific research. The Living Links centre could be a great starting point in children’s engagement with scientific inquiry and the nature of science.

            While walking around the place asking people to fill in surveys about visitor experiences, I get a lot of opportunities to watch the capuchin monkeys go about their day. As I started to observe them, I began seeing a lot of similarities between their behaviour and human behaviour. Capuchins are social animals that form complex relationships and have a wide range of emotions. Watching them interact with each other can be very fascinating and heart-warming. You may also be struck by how intelligent they are, as you observe them playing, using tools, and communicating with each other in sophisticated ways. One thing that stood out to me is the similarity between the dietary habits of capuchin monkeys and human beings and how they do a lot of the same things as humans. They will remove seeds from food like bell peppers and skin from chickpeas (I noticed they are particularly efficient at this one). Compared to larger mammals who are often seen inhaling entire pieces of food at once, capuchin monkeys are more advanced in their methods of dealing with food.

            Perhaps one of the most rewarding aspects of interning at Living Links is the opportunity to build an understanding of the monkeys. Obviously, I am not there yet as I can barely recognise a handful of monkeys. But I hope that over time, I will be able to tell them apart, get to know each individual’s unique personality and preferences, and develop a deep appreciation for the complexity and beauty of their lives.

            I am looking forward to the rest of my internship at Living Links and I am sure this will be an eye-opening experience.