Anthropogenic influences on primate antipredator behavior and implications for research and conservation

Abstract

Predation risk affects prey species' behavior, even in the absence of a direct threat, but human‐induced environmental change may disturb ecologically significant predator–prey interactions. Here, we propose various ways in which knowledge of antipredator tactics, behavioral risk effects, and primate–predator interactions could assist in identifying human‐caused disruption to natural systems. Using behavior to evaluate primate responses to the ongoing environmental change should be a potentially effective way to make species conservation more predictive by identifying issues before a more dramatic population declines. A key challenge here is that studies of predation on primates often use data collected via direct observations of habituated animals and human presence can deter carnivores and influence subjects' perception of risk. Hence, we also review various indirect data collection methods to evaluate their effectiveness in identifying where environmental change threatens wild species, while also minimizing observer bias.

Consistency in the flight and visual orientation distances of habituated chacma baboons after an observed leopard predation. Do flight initiation distance methods always measure perceived predation risk?

“…From 2014, the group received full day (dawn until dusk) follows 3 to 4 days a week, with occasional gaps of up to 5 weeks in duration. The follow schedule was designed to ensure that the study group retained as much of their natural interactions with predators as possible by ensuring that the group had multiple consecutive days without observers who may deter predators or reduce interaction rates (LaBarge et al, 2020; Nowak et al, 2014). During this study, the group contained between 81 and 86 individuals.…”

“…As the baboons were likely to experience heightened stress levels as a result of the predation, their energetic demands should have also increased, potentially leading to fatigue and lowered risk responses (VOD and FID). Alternatively, reduced VODs and FIDs may also suggest the animals increased their tolerance to observers (or reduced their fear perception of the observers) temporarily as observers are known to displace predators (LaBarge et al, 2020), thus proximity to observers may decrease their likelihood of encountering the predator again, that is, the human‐shield effect (Nowak et al, 2014).…”

Reactive and pre-emptive spatial cohesion in a social primate

“…We used our model including both relative risk and event variables to assess whether pre-emptive increases in cohesion in high risk locations would render reactionary responses unnecessary but found no evidence to support this prediction. Future studies using methods other than direct observation might investigate this with risk from terrestrial carnivores as our sample size allowed us to focus on risk only from eagles (LaBarge et al 2020). Strategies for evading other predators could also include a greater reactionary change in cohesion.…”

“…For example, McCarthy et al (2019) were able to use images for creating social networks of party association in wild chimpanzees which has been typically measured through direct observation. While camera trapping for studying primate social behaviour is relatively new, these methods could offer a solution when direct observation could alter risk (LaBarge et al 2020).…”

Impact of individual demographic and social factors on human–wildlife interactions: a comparative study of three macaque species

“…Such behaviors naturally present costs to both wildlife and humans, such as increased risk of injury 1 , negative impacts on wildlife physiology 14 and human mental health 15 , increased transactional and opportunity costs to humans 15 , and/or vulnerability to cross-species zoonosis (wildlife) and emerging infectious disease (humans) 16 , 17 . However, such costs may be offset by potential or perceived benefits, such as procurement of high-energy human foods by wild animals 18 and avoidance of natural predators 19 , and human socioeconomic upliftment through activities like ecotourism 3 , 15 .…”