Let's go beyond taxonomy in diet description: testing a trait‐based approach to prey–predator relationships

Abstract

Summary1. Understanding 'Why a prey is a prey for a given predator?' can be facilitated through trait-based approaches that identify linkages between prey and predator morphological and ecological characteristics and highlight key functions involved in prey selection. 2. Enhanced understanding of the functional relationships between predators and their prey is now essential to go beyond the traditional taxonomic framework of dietary studies and to improve our knowledge of ecosystem functioning for wildlife conservation and management. 3. We test the relevance of a three-matrix approach in foraging ecology among a marine mammal community in the northeast Atlantic to identify the key functional traits shaping prey selection processes regardless of the taxonomy of both the predators and prey. 4. Our study reveals that prey found in the diet of marine mammals possess functional traits which are directly and significantly linked to predator characteristics, allowing the establishment of a functional typology of marine mammal-prey relationships. We found prey selection of marine mammals was primarily shaped by physiological and morphological traits of both predators and prey, confirming that energetic costs of foraging strategies and muscular performance are major drivers of prey selection in marine mammals. 5. We demonstrate that trait-based approaches can provide a new definition of the resource needs of predators. This framework can be used to anticipate bottom-up effects on marine predator population dynamics and to identify predators which are sensitive to the loss of key prey functional traits when prey availability is reduced.

Morphology predicts species' functional roles and their degree of specialization in plant–frugivore interactions

“…We therefore recommend using quantitative tests (e.g. the fourth-corner analysis for species interactions in ecological networks [5,45]) to identify relevant functional traits that determine the interaction. figure 4b).…”

Traits of litter‐dwelling forest arthropod predators and detritivores covary spatially with traits of their resources

“…Tools that allow us to extrapolate the effects of food web structure on ecosystem function are needed. Examples of trait matching include the length of pollinator tongue and corolla depth of flowers (Ibanez 2012), biting force of ground beetles and cuticular toughness of prey (Brousseau et al 2018b) and lipid content of predatory marine mammals and caloric content of prey (Spitz et al 2014). Trait matches that predict interactions can be validated through lab arena experiments (e.g., Brousseau et al 2018b) or through models analyzing well-resolved food webs (e.g., Laigle et al 2018).…”

Trait‐mediated foraging drives patterns of selective predation by native and invasive coral‐reef fishes

“…Empirical work on foraging traits has primarily focused on the effects on patterns of consumption of intra-specific or inter-specific variation in behavioral traits exhibited by predators or prey, either experimentally (e.g., Cooper et al 1985; reviewed by Boukal 2014 for aquatic systems) or observationally (e.g., in fishes [Green and Côt e 2014], birds [Dehling et al 2016], and mammals [Spitz et al 2014]). Empirical work on foraging traits has primarily focused on the effects on patterns of consumption of intra-specific or inter-specific variation in behavioral traits exhibited by predators or prey, either experimentally (e.g., Cooper et al 1985; reviewed by Boukal 2014 for aquatic systems) or observationally (e.g., in fishes [Green and Côt e 2014], birds [Dehling et al 2016], and mammals [Spitz et al 2014]).…”