Reactive anti-predator behavioral strategy shaped by predator characteristics

Abstract

Large mammalian herbivores use a diverse array of strategies to survive predator encounters including flight, grouping, vigilance, warning signals, and fitness indicators. While anti-predator strategies appear to be driven by specific predator traits, no prior studies have rigorously evaluated whether predator hunting characteristics predict reactive anti-predator responses. We experimentally investigated behavioral decisions made by free-ranging impala, wildebeest, and zebra during encounters with model predators with different functional traits. We hypothesized that the choice of response would be driven by a predator’s hunting style (i.e., ambush vs. coursing) while the intensity at which the behavior was performed would correlate with predator traits that contribute to the prey’s relative risk (i.e., each predator’s prey preference, prey-specific capture success, and local predator density). We found that the choice and intensity of anti-predator behaviors were both shaped by hunting style and relative risk factors. All prey species directed longer periods of vigilance towards predators with higher capture success. The decision to flee was the only behavior choice driven by predator characteristics (capture success and hunting style) while intensity of vigilance, frequency of alarm-calling, and flight latency were modulated based on predator hunting strategy and relative risk level. Impala regulated only the intensity of their behaviors, while zebra and wildebeest changed both type and intensity of response based on predator traits. Zebra and impala reacted to multiple components of predation threat, while wildebeest responded solely to capture success. Overall, our findings suggest that certain behaviors potentially facilitate survival under specific contexts and that prey responses may reflect the perceived level of predation risk, suggesting that adaptive functions to reactive anti-predator behaviors may reflect potential trade-offs to their use. The strong influence of prey species identity and social and environmental context suggest that these factors may interact with predator traits to determine the optimal response to immediate predation threat.

Landscapes shaped from the top down: predicting cascading predator effects on spatial biogeochemistry

“…We see research that focuses on functional traits of animals (sensu Schmitz and Leroux 2020, McCary and Schmitz 2021, Sebastián‐González et al 2021, Suraci et al 2021) combined with an understanding of key ecosystem characteristics as the way forward for disentangling these context dependencies to yield broader insights. As an example, identifying which predator–prey interactions are most likely to yield strong spatial responses in food webs with multiple predators and prey (Palmer and Packer 2021), how individual prey species responses to predators aggregate to determine net prey community effects on biogeochemistry (le Roux et al 2018, 2020) and understanding underlying patterns of nutrient colimitation (Kaspari and Powers 2016), will allow for a stronger mechanistic understanding of the role animals play in spatial ecosystem configuration. Thus, we may begin to understand how predator‐driven zoogeochemistry impacts spatial patterning not only in the context of simple linear food chains in model ecosystems, but in complex networks of species interactions across varying environmental conditions.…”

Behavioural changes in aposematicHeliconius melpomenebutterflies in response to their predatory bird calls

“…Anti-predatory strategies are widespread in prey animals and can be morphological or behavioural. Morphological strategies include aposematism, chemical toxicity, and crypsis (Rojas et al, 2019; Vallin et al, 2006), while behavioural anti-predatory strategies include active evasion of predatory attacks, and behaviours that decrease detection (Palmer & Packer, 2021). Anti-predatory strategies can also be a combination of both morphological and behavioural strategies such as the deimatic displays in mountain katydid Acripeza reticulata and swallowtail butterflies (Olofsson et al, 2012; Umbers & Mappes, 2015).…”

Behavioral responses to anthropogenic noise at highways vary across temporal scales

“…Within these human-dominated ecosystems, human activity can elicit fear responses from wildlife species by altering stress physiology, spatiotemporal habitat use, and behavior (Støen et al, 2015;Hammond et al, 2020). Fear is defined in the present study as a reactive, anti-predator behavioral response to an environmental stimulus (Palmer and Packer, 2021) and fear responses to human disturbance are presumed to be analogous to prey responses to predators (Lima and Bednekoff, 1999;Frid and Dill, 2002). These fear responses may result in modification to predator-prey interactions, and lead to trophic cascading effects, ultimately altering ecosystem structure and function (Kuijper et al, 2016;Schmitz et al, 2018;Zanette and Clinchy, 2019).…”