Social Context Modulates Predator Evasion Strategy In Guppies

Abstract

Social context is a powerful mediator of behavioral decisions across animal taxa, as the presence of conspecifics comes with both costs and benefits. In risky situations, the safety conferred by the presence of conspecifics can outweigh the costs of competition for resources. How the costs and benefits of grouping influence decisions among alternative antipredator behaviors remains largely unexplored. We took advantage of the Trinidadian guppy (Poecilia reticulata) to examine the influence of social context on alternative behavioral responses to threats. We compared the frequency of active (startle) versus passive (freeze) responses to sudden acoustic stimuli in the presence and absence of conspecifics. We found that fish were relatively less likely to startle and more likely to freeze when in a group than when alone, indicating that immediate social context modulates predator evasion strategy in guppies. We suggest that these social context‐dependent changes reflect trade‐offs between survival and energy expenditure. To our knowledge, an effect of immediate social environment on startle probability has not been previously demonstrated in a teleost.

Testing the stability of behavioural coping style across stress contexts in the Trinidadian guppy

“…have been demonstrated previously as alternative stress-response behaviours in guppies, using OFTs that did not include a shelter (Fischer, Schwartz, Hoke, & Soares, 2015). We note that freezing and hiding are both effectively passive, "conservation-withdrawal" strategies, and might therefore be considered alternatives among more "reactive" individuals (Øverli et al, 2007).…”

“…Together, these two axes potentially correspond to multiple strategies for behavioural control of a stressful environment: individuals may seek refuge in the shelter, but otherwise may adopt a strategy of either freezing in place (typically in an exposed area) or actively trying to escape the situation. “Freezing” vs. “active startle” have been demonstrated previously as alternative stress‐response behaviours in guppies, using OFTs that did not include a shelter (Fischer, Schwartz, Hoke, & Soares, ). We note that freezing and hiding are both effectively passive, “conservation‐withdrawal” strategies, and might therefore be considered alternatives among more “reactive” individuals (Øverli et al., ).…”

Stimulus Contrast Information Modulates Sensorimotor Decision Making in Goldfish

“…In addition to modulating C-start probability, looming contrast also modulates when animals initiate the C-start. C-start response probability has been shown to be modulated by external factors such as spatial and social context (Eaton and Emberley, 1991;Fischer et al, 2015) and internal state variables such as hunger level or reproductive or social status (Neumeister et al, 2010;Filosa et al, 2016;Park et al, 2018). Furthermore, intrinsic characteristics of the stimulus such as its modality, temporal dynamics, or directionality have also been shown to shape the characteristics of the C-start.…”

Cognitive Control of Escape Behaviour

“…In addition, the local social environment can also modulate escape behaviour (Box 3). Schooling herring have uniform escape trajectories that are less flexible than the responses of solitary animals, and which decrease the likelihood of collisions [111], and even fast-response systems, such as the C-start in guppies, can exhibit similar dependency [112] (Figure 2, bottom right panel). In crayfish, social hierarchy affects the excitability of the lateral giant (LG) escape circuit in a serotonin-dependent manner [113], causing reduced LG excitability in subordinate individuals, exclusively during conspecific interactions.…”