The effects of predator personality and cognition on predator-prey interactions

Abstract

Predators and prey are engaged in a struggle for survival, in which both parties impose strong selective pressure on one another. To combat the catastrophic risk posed by predation, prey have evolved a range of adaptations designed to minimise the probability of being encountered, detected or captured by predators, including flexible behavioural responses. The success of predators in capturing prey is also profoundly influenced by the properties of individual predators, including their behavioural traits and cognition. In particular, consistent inter-individual differences in predator behaviour, or predator personality, have the potential to shape the behavioural decisions of predators at multiple stages of their interaction with prey, ultimately affecting the level of predation risk facing prey. In this thesis, I explore the effects of predator personality and cognition on predator-prey interactions, by studying three species of freshwater fish: three-spined sticklebacks (Gasterosteus aculeatus), pike cichlids (Crenicichla frenata) and blue acara cichlids (Aequidens pulcher). In Chapter 2, I begin by examining the effect of the bold-shy behavioural axis on the capacity of individual three-spined sticklebacks to detect prey. In Chapter 3, by presenting wild pike cichlid predators with a prey stimulus in their natural environment, I then explore the relationship between the factors influencing encounter rates and inter-individual variation in the response of predators to their prey. Next, in Chapter 4, I investigate how prey adjust their anti-predator behaviour following exposure to individual pike cichlids with contrasting personalities. Finally, in Chapter 5, I develop an experimental system in which real blue acara cichlid predators interact with robot-controlled prey, in order to test the effect of unpredictable prey escape tactics on learning by predators. Overall, my research points to the limitations of boldness in capturing the risk individual predators pose to prey, thus emphasising the importance of considering inter-individual variation in ecologically relevant behavioural traits.

Date of Award	23 Mar 2021
Original language	English
Awarding Institution	University of Bristol
Supervisor	Christos C Ioannou (Supervisor)