Impacts of Human Observers on Studying Predator-Prey Interactions and Behaviour in Primates by Professor Russell Hill

On 17 July 2025, the Faculty of Science, Engineering, and Agriculture (FSEA) at the University of Venda (UNIVEN) hosted a public lecture delivered by Prof Russell Hill from Durham University, United Kingdom. The lecture, entitled “Impacts of Human Observers on Studying Predator-Prey Interactions and Behaviour in Primates,” aimed to raise awareness among students, academic staff, and researchers about how the presence of human observers can inadvertently alter the natural behaviour of primates, particularly in contexts involving predator-prey dynamics. The public lecture was held in Lab FF017 at the Life Sciences building.

In his lecture, Prof Russell Hill explored how the presence of human observers can unintentionally influence primate behaviour, complicating the interpretation of behavioural data. He emphasised that studies often rely on habituation, assuming animals behave naturally once accustomed to re-searchers, yet this assumption is rarely validated. Prof Hill argued that observer presence may alter the behaviour of both primates and nearby predators. Drawing on case studies from the Sout-pansberg Mountains, he showed that human observers can affect ecological interactions, even after long-term habituation.
A key focus was the “landscape of fear” experienced by Samango monkeys. Prof Hill presented evidence that fear of aerial predators, particularly eagles, influenced monkey behaviour more than food availability. Monkeys used riskier areas more often when researchers were nearby, possibly perceiving them as deterrents to ground predators. Their physical responses to predators also declined with increasing observer numbers, indicating altered risk perception.
Prof Hill also discussed individual variation among Chacma baboons, noting that tolerance of hu-man presence differed and affected social dynamics and threat responses. He highlighted how some predators avoid humans, while others exploit human presence, further complicating preda-tor-prey dynamics. He concluded that observer presence introduces behavioural changes in wild-life, with significant implications for the interpretation of ecological and behavioural research.
Prof Lourens Swanepoel welcomed the attendees and introduced the guest speaker, Prof Hill. He outlined Prof Hill’s academic background, noting his positions at Durham University and as Adjunct Professor at the University of Venda. Prof Swanepoel highlighted his contributions to behavioural ecology, focusing on how predation and fear shape the behaviour of primates and large mammals. He also noted Prof Hill’s long-term leadership of the Primate and Predator Project in the Soutpansberg Mountains, his interdisciplinary work on human-wildlife conflict, and his role in founding Mammal Web, a UK-based citizen science initiative. Ongoing research collaborations be-tween Prof Hill and UNIVEN over the past six years were also acknowledged.
The lecture concluded with closing remarks from Prof Lourens Swanepoel, who thanked Prof Hill for his visit and presentation. He also acknowledged the staff and students for their active partici-pation and valuable contributions. He encouraged ongoing dialogue and collaboration in the field of animal behaviour and reaffirmed the faculty’s commitment to supporting future research.
The lecture was attended by postgraduate students, academic staff, and researchers from various departments, and was supported by representatives from the FSEA Office of the Executive Dean.

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University of Venda
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