Behavioral responses to spatial variation in perceived predation risk and resource availability in an arboreal primate

Abstract

Prey species must often face a trade-off between acquiring resources and minimizing predation risk. The spatial variation in predation risk across a landscape, as perceived by prey across their foraging or home range, creates a "landscape of fear" by which individuals modify their behavior in response to the level of perceived risk. Here, we explored the influence of perceived predation risk, habitat features associated with risk, and fruit availability, on the spatial variation in behavior of the endangered forest-dwelling samango monkey (Cercopithecus albogularis schwarzi). We collected behavioral and location data on two habituated samango monkey groups in the Soutpansberg Mountains, South Africa, between 2012 and 2016. We further collected location data of the samango monkey's acoustically distinct alarm call, which has an unambiguous association with aerial predators, to spatially map perceived risk across the landscape. Using generalized linear mixed models, we found that perceived risk from eagles significantly influenced the spatial distribution of critical life-functioning behaviors, with samango monkeys increasing feeding and foraging in high-risk areas. To mitigate this risk, samangos increased cohesion between group members, which subsequently reduced vigilance levels. Group cohesion further increased in high-risk areas with abundant fruit, relative to high-risk, fruit-poor areas, demonstrating the monkey's foraging/risk trade-off. Feeding was also reduced in areas of low canopy height, while vigilance decreased with increasing understory visibility and distance from sleep site, showing the influence of landscape features on risk perception from other predator guilds. Thus, for arboreal species foraging in a 3-D landscape, risk perception may occur at multiple scales and in response to multiple predator guilds. Only moving was influenced by fruit availability, either due to moving between localized food patches or from escaping high-risk areas following feeding bouts. These findings highlight that risk-taking in samango monkeys is only associated with behaviors fundamental to survival at a given

It's about time: Feeding competition costs of sociality are affected more by temporal characteristics than spatial distribution

“…Most group‐living primate species are found close to the equator, in less seasonal environments (but see Jones, 2011 ), or in habitats that allow them to switch between seasonally available resources and fall‐back foods (Marshall & Wrangham, 2007 ). Furthermore, primates are able to flexibly adjust their cohesiveness as they move about the “landscape of fear,” increasing density only when predation risk is higher (Coleman & Hill, 2014 ; Parker et al., 2022 ). Thus, the overall costs of gregariousness are likely low for most anthropoids, which helps explain the prevalence of group‐living in this clade.…”

Wild gibbons plan their travel pattern according to food types of breakfast

“…Leaving sleeping trees too early and travelling in darkness not only elevates the risk of falling but may attract potential predators that are active around dawn, such as clouded leopard [62]. However, the benefits associated with gaining prior access to highly caloric, nutritionally rich food items such as fruit probably outweighs the risks of predation and falling for skywalker gibbons [63,64].…”

“…Numbers in italics indicate that explanatory variables had a significant impact on dependent variables. However, the benefits associated with gaining prior access to highly caloric, nutritionally rich food items such as fruit probably outweighs the risks of predation and falling for skywalker gibbons [63,64]. Higher speed could reflect a higher motivation to reach a valuable resource [23,65].…”

MECHANISTIC MODEL OF VEGETATION STRUCTURE AND ANIMAL COMMUNITY INTERACTIONS-INTEGRATING GEDI & TLS DATA IN THE MADINGLEY MODEL

“…We assume that animals feed non-discriminatively across all the height bins they have access to. However, in real life, they are likely to access preferentially some layers, according to their movement capacity, behavioral habits and feeding preferences interaction with food distribution (De Guinea et al, 2019;Delciellos & Vieira, 2006;Dunbar & Badam, 2000;Hopkins, 2011;Mattingly & Jayne, 2004;McClearn, 1992;Milliken et al, 2005;Parker et al, 2022;Schaefer et al, 2002). Animal species traits interact with vertical plant traits differentiation; for example, leaves traits have been shown to vary vertically (Hagemeier & Leuschner, 2019), which could impact palatability and nutritional value.…”