Risk balancing through selective use of social and physical information: a case study in the humbug damselfish

Abstract

To effectively balance the need to forage against the need to avoid predation, animals should utilize information from both their physical and social environments. However, most studies have considered these factors in isolation and few have investigated how animals change the use of these cues temporally. Using novel 3D modeling of the environment and 3D observations of fish movement, we investigated how local abiotic and biotic features of the environment, along with tidal patterns, impacted risk‐related behaviors using humbug damselfish, Dascyllus aruanus, in coral reef habitats as a model system. We found that damselfish balance risk by utilizing cues from both the physical and the social environment, although the relative importance of these cues changes according to tide. At flowing tide, when food resources are typically more abundant, damselfish increased their foraging behavior, but only when their external social environment offered protection from predation. At slack tide, when food resources are typically less abundant, damselfish were not responsive to their external social environment. Regardless of tide, damselfish living in smaller corals showed more risk‐averse behavior, emphasizing the importance of local refuge availability on risk perception. Our results underscore the flexible use of social and physical information along temporal scales and how both biotic and abiotic features influence the trade‐off adopted between foraging and refuging behavior.

Space partitioning within groups of social coral reef fish

“…Larger fish generally ranked higher and foraged farther up-current than smaller individuals, capturing more zooplankton (Webster and Hixon 2000) and higher proportions of larger prey (Coates 1980;Forrester 1991). By investigating the proportion of fish outside the coral, zooplanktivorous fish were found to balance risk by utilizing environmental and social cues (Hansen et al 2016a;Kent et al 2019). Due to technical limitations, none of those studies relied on long-term, high-resolution, 3D tracking of marked individuals.…”

Individual behavioural traits not social context affects learning about novel objects in archerfish

“…Exploring a potential new food source can provide obvious foraging benefits but may expose an individual to potential risk from predation or noxious substances (Lima and Dill 1990). The social environment Communicated by I. Hamilton can play a large role in an individual's motivation to engage with novelty and subsequent learning opportunities (Boogert et al 2006;Mirville et al 2016;Langley et al 2018;Kent et al 2019;Hansen et al 2020). Individuals can be more likely to approach novel foods with conspecifics present (Gómez-Laplaza and Morgan 1986;Sherwin 2003).…”