Master Internships

Please contact the appropriate supervisor in Animal Behaviour and Cognition if you are interested in the following projects as part of a masters study. Please let us know the following when you contact us:

  • Which project you are interested in, and why: please detail your motivation.
  • Your relevant academic experience (for example, have you completed a course in animal behaviour / animal ecology or an allied discipline? Such experience is normally a prerequisite for beginning an internship).
  • Which course you are currently doing, and where you are studying.
  • How long an internship you are looking for.
  • When you would like to start and finish, and your flexibility regarding these dates.

Students from outside Utrecht should inform us of any special requirements made by their home university and must ensure that academic credit earned here is transferable. Please check with your home university that it is possible for you to do an internship here before you get in touch with us.

Projects categorised by topic:

  • Primate social cognition
  • Animal welfare (zoo/lifestock)
  • Diverse topics: Bonobo's, chimpanzees, great tits, a.o.

Primate social cognition: in the Netherlands and elsewhere

1. Anti predator responses of captive primates to acoustic and visual predator models

Many primate species possess specialised anti-predator techniques that enable them to cope with their predators and control mortality risks.  Rapid and accurate predator recognition lies at the core of these techniques, and natural selection should favour mechanisms that facilitate this process. Three basic processes may be at work in helping individuals to recognize and respond appropriately to predators. Firstly, prey animals may possess an inherited predisposition to recognize and respond adaptively to certain animals with anti-predator behaviour. Secondly, predator-naïve animals may not accurately recognise a predator on their first encounter, but they may be equipped with a particularly efficient learning mechanism, which allows them to learn the features of different predator types with a small number of trials, either by experiencing a direct interaction with the predator or by witnessing the anti-predator behaviour of others. Thirdly, it is conceivable that individuals possess some inherited predator knowledge, but that this knowledge is incomplete and requires experience before appropriate anti-predator behaviour is possible. For example, in some animal species accurate predator recognition in the visual domain appears to be less experience-dependent than recognition in the acoustic domain: in this case animals may lose a specific response evoked by a particular predator type, while retaining more general antipredator behavior evoked by archetypical cues that are shared by a class of predator species (e.g. predator shape). In this study, we will subject captive individuals to the sights and sounds of different predator types and determine whether their species-specific vocal and behavioural anti predator responses to both the sights and sounds have been retained under relaxed selection pressures over several generations. 
Contact:  Start February 2023 - October 2023. Dr. Anne Marijke Schel (

2. Budongo (Uganda): Is vocal behaviour of Guereza colobus monkeys affected by predator pressures

This study will look into Guereza colobus monkeys’ dawn chorusing behaviour and investigates whether or not the dilution effect may explain the vocal behaviour of these animals. A 2010 study on guereza colobus monkeys showed that these monkeys reliably responded to playbacks of conspecific dawn chorusing, even if this meant they were the only two males calling in the area.  This has been linked to a male rivalry function in this species, allowing individual males (who lead a group of females) to indicate their fighting ability. Eight years later, in 2018, guerezas in the same study area were very reluctant to start calling back in response to playbacks of conspecific male dawn chorusing. Circumstantially, in the approximately 10 years since the previous playback experiments had been conducted, chimpanzee hunting pressures have risen substantially. To find out if the monkeys have adapted their calling behaviour to this increased predation pressure, this study will use playback experiments to investigate whether males that are reluctant to respond to played back dawn choruses by themselves are more likely to start calling when multiple males are already calling in the area (either in response to the playback or playback induced). This would still show their fighting ability to neighbouring males, but at the same time they may ‘mask’ their exact location for eavesdropping predators and may become less vulnerable for predator attacks.
Contact: Study ideally starting in March 2023 and conducted at Budongo Conservation Field Station (BCFS) in Uganda- if allowed by UU and BCFS Covid guidelines. Dr. Anne Marijke Schel (

3. Measuring affective states in animals subjected to acoustic and visual predator models

Primates often produce alarm calls in response to different predator types. The acoustic properties of such calls may differ (either gradually or discretely). This difference has been related to the context in which these calls are produced (e.g. the type of predator or its speed of attack) and may be  associated to the affective states experienced by the callers at the moment of call production. In this study, we will subject captive primates to the visual and vocal presence of predator models that are either presented from far away or closeby and aim to capture their vocal and affective anti predator responses. This is done by recording their vocalisations and changes in body temperature and relating the call specific vocal parameters and accompanying changes in temperature to the current literature on animals’ affective behaviour.
Contact: Start October 2022- January 2023. Dr. Anne Marijke Schel (

4. Laterality of hand use during the initiation of play

Several primate species communicate with their conspecifics through the use of body signals. These include body postures and body movements, as well as particular movements of hands, feet, limbs and head. If these signals are produced flexibly with an intention to change the behaviour of the recipient, these signals are called gestures. Thus, gestures can be used flexibly to facilitate efficient communication between signallers and recipients, and some researchers have suggested that gestural communication may lie at the base of our own extraordinary capacity for language. One line of evidence supporting these claims comes from studies on manual laterality during gesture use. These studies show that in some primate species a right hand preference during the production of communicative gestures is found, in combination with strong neuronal firing activity during such (manual) gesture production in a particular neuroanatomical area of the left cerebral hemisphere that has been linked to speech production in humans (a homologue of Broca’s area). Thus, it appears that the left brain hemisphere is in control during such ‘formal’ communicative events, leading to a right hand preference for such formal communication. During play, however, gestures from a variety of ‘formal’ communicative contexts are used,  but are clearly produced in a less formal communicative context: this may lead to a less strong hand preference for producing gestures during play. This research will explore whether the handedness of communication during play differs from that in other settings.
Contact:  Start October 2022- January 2023. Dr. Anne Marijke Schel (

5. Regulation of primate relationships in macaques: the role of tolerance and cooperation

Group life is only possible when benefits outweigh the costs. However, group members may have different needs and compete with each other. Animals navigate this social environment by forming social relationships with their group members. Traditionally, aggression and the related dominance hierarchy has received most attention. However, it is becoming clear that also friendly relationships are important. While friendly relationships result in fitness benefits, the underlying mechanisms are not clear.
In this research we explore how macaque friendly relationships relate to tolerance in food tasks. This research combines an observational and experimental (by giving enrichment) approach.
Researcher: Prof. dr. Liesbeth Sterck (email:
Application: at least one month before start student research (a researcher may not be able to place a student in such short notice)
Requirements: course in 'Socioecology'; course in statistics

6. Is yawning in chimpanzees related to stress or vigilance?

Project duration – 8 to 9 months (incl. 5 – 6 months of rigorous fieldwork in Burgers’ Zoo, Arnhem)
Yawning is an evolutionarily old behaviour that is widespread among vertebrates. However, there is still much debate on its function. The hypothesis that it serves to increase oxygen uptake, although still pervasive, has been proven false long ago. On a proximate level there is, however, convincing evidence that yawning serves a thermoregulatory function, i.e. it cools the brain back to homeostasis. But the ultimate reason why animals do that remains unknown. Yawning has been linked to arousal levels and stress. Alternatively, it is thought that by cooling the brain, yawning induces vigilance. Evidence for the vigilance hypothesis is still lacking, but there are some studies that indirectly support it.
The aim of the proposed project is to further investigate both the stress and the vigilance hypothesis and we do this by looking at post-conflict yawning in a group of captive chimpanzees and by investigating the effects of reconciliation and consolation on those post-conflict yawning rates. Conflicts induce stress and the possibility of renewed aggression may require vigilance. Reconciliation and consolation influence these patterns differently. This study requires a lot of observational hours to get as many conflicts as possible, as well as the required matched controls.
We’re looking for a highly motivated, contentious and patient student that wants to do that extra mile. Experience with behavioural observations of a social species is preferred.
Supervisor: Dr. Jorg J.M. Massen (

7. Social cultures in macaques?

In humans, not all groups are equally social. For instance, there are large differences across cultures to what extent humans seek each other’s physical presence. In turn, such differences may correspond to opportunities to learn from each other, help one another, and/or collaborate with group members. Despite its established relevance in humans, the extent of group-level sociality in non-human animals hardly plays a role in understanding animals’ behaviour. Moreover, if we want to track the evolutionary origins of human behaviour, we need to understand the extent to which related species differ among groups. In this project, we will investigate how much groups of macaques vary in their social behaviour, both at the individual, dyadic and group level. Method. We will study 8-12 groups of macaques at the BPRC using established behavioural sampling methods. Here, the focus will be on scoring social interactions (proximity, grooming, sex, play, aggression, displacement). The data will be analysed with state-of-the-art statistical techniques (Bayesian generalized linear mixed models) of which template scrips are available. Moreover, social network analyses will be applied including the generation of graphical visualizations. We seek highly motivated students (2) to conduct observations on macaques, with a specific focus on applying statistics to behavioural data. The student will be challenged to acquire knowledge on social behaviour in macaques, on Bayesian statistics and social network analyses in order to pursue the exciting new question: do non-human animals also have social cultures?
Contact: Edwin van Leeuwen:

8. Something’s gotta give! Social tolerance in monkey societies

Social tolerance refers to the ability to be in each other’s social space without pronounced aggression. As such, social tolerance has been identified as an important phenomenon with the potential to facilitate behaviours with immediate benefits, like cooperation and social learning. Yet, how can we measure social tolerance? And is social tolerance a species-specific trait or does it vary from group to group? In this project, we will experimentally test the extent of social tolerance across multiple groups of macaques. Here, macaques are an especially interesting family of primates to investigate given the established classification of their social tolerance levels (e.g., egalitarian VS despotic) based on species-wide generalizations. Method. In each group (n=8-12), we will employ a co-feeding experiment consisting of a predetermined arena of limited and depletable food resources from which group members are free to feed. We will measure how many group members can simultaneously benefit from the food resource and compare these numbers across groups to assess potential group differences. Furthermore, we will use focal sampling techniques to measure dyadic tolerance levels within the experimental arena (e.g., in terms of socio-positive behaviours, food sharing, and displacement). Lastly, we will apply social network analyses to obtain insights into metrics of social tolerance beyond the dyads. We seek highly motivated student(s) to conduct simple experiments with rhesus and long-tailed macaques at the BPRC, Rijswijk. The student will have the exciting chance to acquire knowledge on social behaviour in macaques and social network analyses in order to challenge the established idea that macaques can a priori be grouped at their species level to assume their group-specific climates of social tolerance.
Contact: Edwin van Leeuwen:

9. Food sharing in bonobos and chimpanzees

Food sharing in the Pan species (chimpanzees and bonobos) has been studied for its potential to assess whether prosociality (benefitting others) is a derived trait in the human lineage or rather an evolutionarily older proclivity shared with humans’ closest living relatives. Whereas research from wild populations indicates that chimpanzees share meat after successful hunts, not much is known about their food sharing tendencies in general, and the extent to which group-specific dynamics may preclude species generalizations. In the current study, we will investigate if groups of bonobos and chimpanzees share food with their group members and, if so, what factors may drive their prosocial giving. Method. We will conduct a food sharing experiment in which one bag filled with carrots, or carrots and apples (TBD), will be placed in the ape group after which the ensuing dynamics will be monitored by means of focal follow procedures with cameras. We will conduct 8-10 sessions per group. The focus will be on scoring the frequencies and types of food sharing, including the dynamics of the identities of the food owner and potential food recipient. The scoring of these elements will be done from video recording afterwards, but during the recording we will narrate the dynamics to facilitate coding afterwards. We seek highly motivated students (2) to execute these experiments, possibly in the Chimfunshi Wildlife Orphanage (Zambia). The PI is an experienced researcher and member of staff at CWO and might join you to familiarize with the setup. The student(s) will be challenged to work remotely in a very safe sanctuary setting with good communication channels. The student(s) will have to cover the costs for this experience abroad themselves. For more information, please contact the PI.
Contact: Edwin van Leeuwen:


12. The effect of out-group competition on ingroup social cohesion, prosociality and cooperation in macaques

Current geopolitical developments clearly show that people, like other social animals, tend to think in us and them, and when competing with an outgroup tend to close ranks and increase in-group cooperation. What is cause and effect of this pattern, also referred to as parochialism, remains largely obscured. In this study we aim to study this parochialism in multiple groups of rhesus monkeys, a model species for human behaviour. The proposed set-up allows testing the relationship between out-group competition on (1) social cohesion, (2) in-group prosociality and (3) cooperation. I will focus my investigations on behavioural- as well as hormonal- and genetic markers. Specifically, we will use well-known paradigms to test cooperation and prosociality in a group setting while the macaques experience various degrees of out-group competition.
The project involves testing multiple groups of rhesus macaques in their natural groups rendering ecological relevance.
We are looking for two highly motivated students for this exciting research. Students will learn behavioural sampling techniques, macaque behaviour, data coding, statistical analyses, and scientific writing.
Project duration – 6 - 8 months (incl. 5 – 6 months of observations/experiments at BPRC, Rijswijk, NL)
Project start date – Flexible, preferably by autumn 2022.
Supervisors – dr. Jorg JM Massen (
Contact me with a short letter of motivation and CV.

13. Maternal-infant emotional relationship: Infants’ temper tantrums

Early in life, infants develop a distress vocalization calls (geckers, screams, etc.), usually a high peep vocalization used to get into proximity or direct nipple contact with their mothers (sometimes non-mothers’ caretakers). This behaviour is produced during the maternal care window, in which the infant/juvenile requests contact and/or food, during lactation (Kret et al., 2020). This alerts the mother to the infant’s need. This behaviour, however, develops during the first months of the infants’ life. When infants get older, the mothers reduce their time spent with their infant. In this period, mother-infant conflict and mothers’ rejection increases over time, reducing the time spent in contact and the access to the nipples. That is when the “weaning conflict window” or also called “parent-offspring conflict” starts. In this time window, the infant tries to “manipulate” and get into contact with its mother outside of danger or need, producing a specific vocalization called a “temper tantrum” (a high speech vocalization combined with a behavioural exaggeration of his/her needs that can last for even minutes). The project thus aims at getting a better understanding of this phenomenon using physiological (facial temperature) and behavioural parameters (vocalizations, social behaviour etc.).
Contact: Paula Escriche Chova (; start October 2022

14. Infant’s emotional expression. How does a newborn affect the behaviour and physiology of its older sibling in rhesus macaques?

Mother-infant relationships is the first and most important attachment in humans’ and animals’ life. Although this attachment is essential for physical and emotional well-being, this attachment also comes with negative consequences over time. Animals’ studies show how mother’s rejection and unavailability affects the infant development as well as it is seen as a stressful situation for the infant. One example of mother-infant conflict is the transition to siblinghood (TTS). TTS is a stressful and emotional event for an older sibling that occurs after the sibling’s birth, and it comes along with the “weaning conflict”. In point of fact, Behringer et al (2022) found higher urinary cortisol in these animals after the sibling birth and these higher cortisol levels were not reduce for seven months in bonobos. In this study, we aim to observe how the birth of a sibling affects the emotional processes of the older siblings (1-2 years old infants) in a different primate, in rhesus macaques. We aim to combine physiological (hair cortisol and facial temperature) and social behavioural (vocalizations, social behaviour, etc.) measurements to better understand this phenomenon.
Contact: Paula Escriche Chova (; start: January 2023

15. Maternal emotional expression towards their infant’s fear scream and positive interactions

Primates’ motherhood is commonly characterized by carrying their infants, breastfeeding their infants for more than a year, spending greater time in contact, and protecting their infants when facing aggression from other animals. In rhesus macaques, mothers are highly motivated to spend great deal of time nursing, in vetro-ventral position with their infants and react to infant’s vocalizations during the first months of life, which it reduced after the “maternal care window”.  Recent research shows that this mother’s motivation is regulated by emotional processes and is reduced during the “weaning conflict” period. We therefore want to study how emotional mother-infant interactions are and how they change over time in a natural group living setting. We aim to study the emotional effect of positive (grooming, nursing, etc.)  and negative (distress calls, aggression towards the infant, etc.) mother-infant interactions on mothers during their first months of the infant’s life.
Contact: Paula Escriche Chova (; start: January - February 2023

16. Group-service in rhesus macaques: prosociality and social learning

Group living animals compete and cooperate with their group members. Yet while competition may be easily understood, elucidating the evolutionary mechanism of cooperation has proven to be challenging despite theoretical and empirical explanations. This is particularly the case when animals provide others with a benefit, while they do not gain themselves. Especi8ally animals with a clear and despotic dominance hierarchy, like rhesus macaques, may find it difficult to provide others. To test this hypothesis, we will test the monkeys with a group service paradigm in their social group, where the individual that pulls the apparatus cannot obtain food itself, but does provide group members. We will also study how they operate the apparatus and whether they learn individual or socially. Several groups will be tested.
Project duration: 6 - 8 months (incl. 5 – 6 months of observations/experiments at BPRC, Rijswijk, NL)
Project start date: Preferably by October 2021
Supervisors: Liesbeth Sterck ( and dr. Jorg JM Massen (
Requirements: We are looking for a highly motivated students for the project.

17. The primate gut-brain axis: Is gut microbiome composition associated with stress-related behaviors in zoo-housed bonobos?

The microbes living in our gut are known to play an important role in regulating our physical and mental health. However, recent literature also emphasizes the potentially major role of the gut microbiome in the regulation of brain function and behavior. Gut microbes are crucial for the proper development and regulation of behavior and cognition, giving rise to a connection between the brain and the gut, known as the gut-brain-axis. Conversely, the social behavior of the host itself will directly influence the composition of the gut microbiome, indicating the axis is bidirectional. To date, very little is known about the gut-brain axis in animals, especially in non-human primates. Therefore, the aim of this study is to characterize the bonobo gut microbiome and to investigate if gut microbiome composition is associated with stress-related behaviors in a large multi-zoo sample of bonobos. The student will aid in laboratory analysis of the fecal samples starting September 2022 (KULeuven, Belgium) and work with existing behavioral datasets to link to the microbiome profiles. Behavioral data collection would not be required, but could be included for Planckendael bonobos if there is interest, rather than doing laboratory analysis of fecal samples.

  • Laboratory analysis to produce microbiome profiles at KULeuven starting September 2022 (date can change slightly depending on completion of fecal sampling by then).
  • Analysis of individual microbiome profiles to inform 11 zoological institutes on their bonobos in comparison to the other zoos that participated in the project. 
  • If behavioral data collection: Uninterrupted availability for 3 consecutive months to collect data. Your own laptop is required to install observer software and fast and blind typing is crucial for successful completion of this project.

Contact: Jonas Torfs and Nicky Staes

18. Behavioral responses to long calls of zoo-housed Bornean orang-utans (Pongo pygmaeus)

Project duration – 9 months (major) or 6 months (minor).
Location – Apenheul Primate Park (Apeldoorn, The Netherlands).
Summary – Orang-utan males are known for their large cheekpads and impressive long calls. The long call has multiple functions, such as deterring other males, attracting females (e.g. Mitra Setia & van Schaik, 2007), and communicating travel direction (van Schaik et al., 2013). Possibly, the long call contains information about health, identity and dominance of an individual (Askew & Morrogh-Bernard, 2016). Importantly, not only flanged males produce long calls. Unflanged males that are transitioning towards flanged males already start producing proto-long calls. However, these calls do not have the same intensity yet as those of fully developed males.
In this project, we will study whether female orang-utans respond differently to the calls of flanged males or unflanged males. We will do this using a playback setup, where we play short fragments of long calls, and videorecord the behavioral responses of the orang-utans before, during and after the sound stimulus onset. Apart from this, you will be expected to record behaviour of the orang-utans outside of the playback sessions. By observing the behaviour of the orang-utans during the study period and after the study period, we hope to be able to investigate how an experiment like this affects the welfare of the orang-utans over a longer time period.
NOTE: at the start of the project we will first pilot the playback setup with the orang-utans. If the zoo thinks that the playbacks are too stressful for them, we might have to switch to an observation-only design. However, it is unlikely that this will happen.
Project start date – Flexible, preferably as soon as possible. Supervisors – Tom Roth (Animal Behaviour & Cognition, UU,
Requirements – I am looking for a motivated student with good communication skills, because this project will also involve contact with animal caretakers. Previous experience with observing primates and working with BORIS are a plus, but not essential.

Bird Internships

19. Social structure of Rüppell's vultures

Traditionally studies on social cognition have focusses on primates, rendering specific hypotheses about the evolution of (social) intelligence. Yet, to study the generalizability of these hypotheses, it is paramount to also test them in other taxa. Recent studies have started to also look at birds, but are restricted to two groups of species that are known for their intelligence, i.e. corvids and parrots. Little is known about other species of birds. A group of birds that is largely overlooked are vultures, specifically so because recent analyses revealed they have relatively (to body size) big brains. Therefore, in this project we want to investigate social intelligence of vultures, and specifically of Rüppell’s vultures, which along with some other vulture species, is a social species. To set the groundwork we are firstly interested to describe the social structure of these vultures and to infer from these data whether they have for example a linear hierarchy, have knowledge about such a hierarchy, show demarcated social relationships (e.g. friendships) etc etc.
The project involves testing and observations of 1 group (potentially more) of Rüppell’s vultures  in their natural group rendering ecological relevance.
We are looking for two highly motivated students for this exciting research. Students will learn behavioural sampling techniques, vulture behaviour, data coding, statistical analyses, and scientific writing. As the project is relatively explorative, we specifically welcome students with own ideas.
Project duration – 6 - 8 months (incl. 5 – 6 months of observations/experiments at Avifauna, Alphen a/d Rijn NL);
Project start date – Flexible.
Supervisors – dr. Jorg JM Massen ( Contact me with a short letter of motivation and CV.

20. What explains individual and species differences in innovative ability?

The environment around us is constantly changing, and as humans we are capable of adapting ourselves to these changes, finding new ways to overcome difficulties that we encounter and using what we already know. However, we are not the only species capable of doing this.  There are many examples of how animals can solve problems they encounter and use this knowledge in new ways. A key factor for this is innovation ability. This ability, however, varies between species, populations, and even individuals within populations. Although studies on innovative ability have shown the importance for adaptation and fitness, it is still largely unclear why some individuals are capable of coming up with extraordinary solutions to problems whereas others are not.
In this project we investigate which key factors make some animals more innovative than others. We use blue tits, marsh tits and great tits as our study species both in the wild and in captivity.
Work can include: fieldwork, behavioural measures in captivity during summer, autumn and winter, Innovation behaviour in spring; Starting date: any date
Supervision contact details: Kees van Oers (; Utku Urhan (

21. Habitat matching or local adaptation: how does habitat quality drive variation in cognitive traits

The environment is changing rapidly, and it is essential for animals to behaviourally adapt to these changes. In order to adjust their behaviour adaptively they need to collect, retain and use information from their  changing environment, processes referred to as cognition. While cognition is known to be important, we still lack information on the existence of  consistent cognitive differences across habitat types, suggesting local adaptation in cognitive ability. In this project, we will determine whether natural variation in habitat quality acts as a potential selection pressure on cognitive variation in great tits, a model species for ecological cognition.
Work can include: fieldwork, habitat measures, behavioural measures in captivity, Foraging behaviour during winter; Starting date: any date
Supervision contact details: Kees van Oers (; Eva Serrano-Davies (

22. Animal Personality

Animal personality; a topic that has received much attention over the last 3 decades. Within this topic many field, lab, data or literature studies on birds are possible.  Projects could range from behavioural, ecological, fitness to genomics studies, but also studies using a large 25-year dataset on different aspects on animal personality are possible. Any length or type is possible.
Starting date: Very flexible
Supervision contact details: Jorg Massen ( and/or Kees van Oers (

23. The role of birds for managing Oak Processionary Caterpillars

Oak processionary caterpillars (Thaumetopoea processionea ; OPC) have increased in abundance greatly over the last decade. They are seen as a pest, because of their venomous hairs, which can cause skin irritation in humans. Over the past years the role of songbirds, predominantly the great tit (Parus major), as a pest management tool has been widely advocated. However, strong evidence for the effectiveness of an effect of great tits on OPC densities is lacking. In this project, you will be part of a systematic study on the role for passerines in pest management. For this purpose we setup a new nest box population (100 boxes) of great tits in ‘s Gravenlande's Buitenplaatsen around the Natuurmonumenten Bezoekerscentrum “Gooi- en Vechtstreek” . With over 600.000 visitors yearly and an increasing density of OPC, this area is ideal for this study. We look for students that want to do projects on questions related to the foraging behaviour of great tits throughout the year during nestling periods (April, May, June) and/or fledging periods (June, July, August) or winter (September-March). Also possibilities on insect ecology or combinations are possible.
Work includes: Field work in ‘s Gravenland, video recordings, camera traps, insect work, behavioural observations; Starting date: Flexible
Supervision contact details: Kees van Oers (


Other internships


24. Primate welfare: the effect of movement on primate overweight

Overweight is a large-scale problem in captive animals. Preventing overweight is important to promote animal welfare, since overweight may lead to several health problems, such as diabetes and cardiovascular diseases. Also in group-housed macaques that live in spacious enclosures, a portion of the animals carry a few extra pounds. Preliminary data indicate that overweight animals do not have a higher food intake, but are more often inactive. We seek confirmation of this connection between behaviour and overweight. Moreover, we plan to test the effect of a change in animal management on overweight. This contributes to our understanding how management can be adjusted to improve animal welfare.
During a nine-month internship on the macaques living at the Biomedical Primate Research Centre (Rijswijk, NL) you will participate in a project that aims to enhance healthy behaviour in macaques.
Researcher: Dian Zijlmans (email:
Application: internships are available, preferably starting between October 2019 / January 2020
Requirements: course in 'Socioecology'; course in statistics


ZOO welfare program


25. Monitoring behaviour and welfare of intact and castrated male Western lowlandgorillas (Gorilla gorilla gorilla) in Dutch zoos (Apenheul)

In EAZA zoos, Western lowland gorillas (Gorilla gorilla gorilla) are part of an Ex situ breeding Programme (EEP) to maintain a genetically healthy and demographically stable population. Preferably, gorillas are housed in their naturalistic social organisation of polygynous groups. However, a surplus of adult males exists for whom no place is available as harem group leaders. Finding a long-term management strategy for these animals considering their welfare is challenging. Pre-pubertal castration is one of these strategies, as this may allow these males to remain in their natal group after adulthood. However, only anecdotal information is available on the long-term effects of castration for this species. This study monitors the behaviour and welfare of intact and castrated male gorillas in Dutch zoos by observing (social) behaviour and non-invasively measuring faecal stress (-hormone) levels. You will be participating in this longitudinal study by collecting behavioural and physiological data of surplus male gorillas in seven Dutch zoos and investigating a specific research topic. Experience with behavioural observations is required for this project, as are a strong sense of responsibility, good communication skills and being able to work independently.
Internship positions available: 2
Contact person: Lisette van den Berg (Apenheul Primate Park, NL);

26. Investigate the effects of restricted breeding policy on the behaviour, social dynamics and welfare of Barbary macaques (Macaca sylvanus) in three Dutch zoos (Apenheul)

Many endangered animal species in EAZA zoos are part of an EAZA Ex situ Programme (EEP); an international breeding program. Breeding policies can differ per species and range from uncontrolled breeding and restricted breeding to non-breeding (in either single sex groups or mixed-sex groups). For the Barbary macaque (Macaca sylvanus) restricted policies in mixed-sex groups currently apply: some individuals are free to reproduce, while other individuals are (temporarily) castrated or receive anti-conception to prevent reproduction. This policy offers the opportunity to breed with some of the individuals, but minimizes the amount of surplus animals in the zoo population.
As reproduction and associated behaviours (e.g. mating and rearing offspring) are an integral part of the natural behavioural repertoire of primates, they could be considered important for individual animals. However, to date, few studies have investigated the actual effects of (non-)breeding on (social) behaviour and welfare of individual animals and group dynamics in zoos. In this research, behavioural data of Barbary macaques housed at three Dutch zoos with different breeding policies is collected in this longitudinal study. This enables us to compare group dynamics and individual behaviour in groups with and without offspring. In this internship you will be responsible for the data collection and investigating the effects of (young) infants on social dynamics and individual behaviour in these groups. Experience with behavioural observations is required for this project, as are a strong sense of responsibility, good communication skills and being able to work independently.
Internship positions available: 1
Contact person: Lisette van den Berg (Apenheul Primate Park, NL);

Other major/minor research topics


27. Primate welfare: overweight in semi-free ranging Japanese macaques

Overweight and obesity are a large-scale problem in captivity, with 10-15% of captive macaques developing obesity somewhere during their life (West & York, 1998). As activity is limited, food is abundant and easily accessible, living in captivity can be considered an “obesifying” lifestyle (Dittus, 2013). Although semi-free ranging macaques have more natural and spacious homes compared to captive primates, they tend to become overweight as well. We hope that comparing overweight and behaviour of macaques in different housing conditions provides more insight about which factors are related to overweight. This contributes to our understanding of what may cause overweight in group-housed macaques and hopefully result in new management strategies to improve animal welfare.
During a six- or nine-month internship, you will participate in a project that quantifies overweight and behaviour of Japanese macaques living semi-free ranging at the Affenberg in Austria (
This internship requires a motivated student that is willing to spent at least five months abroad, preferably starting in February/March 2020. The student needs to be able to work independently (as the daily supervisor will be guiding tours during the summer), but also be a team-player.
Researcher: please contact Dian Zijlmans at
Application: preferably starting Feb/March 2020.
Requirements: course in 'Socioecology'; course in statistics

The BPRC Primate Welfare Program

The BPRC houses primates and aims at achieving the highest standards of their welfare. The primates are  group-housed and have large enclosures with many enrichment devises. An enrichment manual is output form this research program.
Continuing research aims at further improving primate welfare, improving on each of the three R’s. Research can be conducted in three species: rhesus macaques, long-tailed macaques and common marmosets; on the following topics:
-General behaviour
-Social behaviour
-Positive reinforcement training
-Non-invasive techniques
For information contact:
Liesbeth Sterck:
Annet Louwerse:
Links: BPRC


Minor research projects


Pragmatics in guereza colobus monkey (Colobus guereza) communication

For a master student EB:BE interested in gaining experience in (experimental) fieldwork, a (non-funded) minor research project position is available at the Budongo Conservation Field Station, Uganda.
Fieldwork will be conducted from November 2018 – January 2019 under supervision of Dr. A.M. Schel. She will travel to Uganda with the student and will offer training on field methods for two weeks at the start of the fieldwork period.
Scientific framework:
Although some animal calls appear to function as highly informative ‘word-like’ signals, it was recently suggested that many signals are not produced as context-specific as previously claimed, and that listeners’ adaptive responses are more fundamentally dependent on additional cues to infer the underlying cause of calling (i.e. pragmatic inference). This study will investigate which cues guereza colobus monkeys (Colobus guereza) take into account when responding adaptively to conspecifics’ vocal eagle alarms and dawn chorusing. These vocalizations are acoustically similar, but produced in different contexts, leading to highly differential responses that are needed from recipients.  A playback experiment is conducted to find out whether call-acoustics or additional cues (e.g. daytime) cause listeners to respond adaptively.
If you are interested in doing your minor research project on pragmatic inference in wild black-and-white colobus monkeys in Uganda, please contact Anne Marijke Schel
The selection procedure will involve an interview in the week of the 9th of July 2018.

Fauna conservation and certified forestry in Central Africa

Protection of wildlife in nature reserves is important. However, also protection wildlife in forests that are used for selective logging can also provide a major contribution to maintaining wildlife populations. In this research, we determine the effect of logging practices on wildlife densities in Central Africa. We also measure hunting pressure.
Minimum length of student research: 6 months (data collection, processing of data and writing of student report). Minor/major research project.
Application: Please send your application to Joeri Zwerts (, at least one month before the start of your research project/internship. The availability of research positions will depend on the planning of the introductions.
Requirements: Students participating in this research are required to have followed courses in ‘Socioecology’ and in statistics.

Internships at the Centre for Research and Conservation, Antwerp Zoo, Belgium

The Antwerp Zoo Centre for Research and Conservation (CRC) is the research department of the Royal Zoological Society of Antwerp (RZSA). Research activities take place mainly at ZOO Antwerpen at the ZOO Planckendael, and in associated institutions.
Students that would like to conduct a master project can contact Zjef Pereboom ( or Marjolein Osieck ( Please indicate your master program; your interests (e.g. zoo animal welfare; conservation genetics; social behaviour; cognition; et cetera); why you want to conduct research at the CRC, Antwerp Zoo, Belgium; when you would like to start; and how much time you can spend (for Major research project: 9 months). For more information about research done at the CRC visit

Internship at Stichting AAP, Almere

AAP, Sanctuary for Exotic Animals, is located in Almere, The Netherlands. Exotic mammals (mainly primates, but also raccoons, squirrels and other small mammals) rescued from all over Europe are rehabilitated at our sanctuary and when fully rehabilitated, will be rehomed to high-quality zoos, animal parks or wild reserves. At the sanctuary, we perform several behavioural studies.
For current studies and internship possibilities, please contact Charlotte Kluiver ( Please indicate your master program, your interests, your preferred start date and how much time you want to spend on this internship. We have a minimum research length of 6 months. For more information visit