Abstract
Finding food is central to animal fitness. Natural selection will thus act strongly upon traits that drive successful foraging. Yet, we know surprisingly little about the individual and social traits that influence foraging success in the wild, due to the difficulty of conducting group-level manipulations and replications under natural conditions, especially in vertebrate species. Here, I propose to study the individual and social determinants of foraging success, using the Trinidadian guppy (Poecilia reticulata), a well-studied model-system that allows ecologically-realistic and effective group-level manipulation and replication in the wild. Individual foraging behaviour can co-vary with the physical phenotype of the forager (e.g. sex and size), but also with its behavioural type. In many species, certain individuals are consistently more risk-prone, exploratory, and/or active than others and I hypothesize that such behavioural differences influence an individual’s ability to find food. Next to relying on their own ability and information, individuals can also benefit from foraging with others. Such social benefits, I hypothesize, will depend on how successful a forager is alone, the food finding abilities of others and the social network dynamics within populations. First, I will test (1) if solitary foragers consistently differ in foraging success, by trans-locating individuals across environments in the wild, thereby breaking individual by environment correlations. I will test (2) which physical and behavioural traits predict solitary patch discovery and (3) if poor solitary foragers are more social than successful solitary foragers and consequently discover substantially more patches when foraging with others. Finally, by manipulating group compositions, I will test (4) if individuals, with traits that predict strong solitary foraging ability, can disproportionally influence foraging success of other individuals in their social environment. My project will combine experimental rigor with ecological relevance to considerably advance our understanding of the factors that drive foraging success in the wild.
Netherlands