The Influence of Individual Physiology on Group Behaviour in Fish Schools

Killen

The behaviour of schooling fishes is one of the most fascinating phenomena in the animal kingdom, and images of shimmering fish schools have become emblematic of the aquatic world. In addition to being aesthetically captivating, schooling behaviour is also of great biological importance, playing a role in the foraging and predator-avoidance behaviour of multiple species in both freshwater and marine ecosystems. The fluid, synchronous movement of fish schools has long been studied, but it is still unknown how the behaviour of individual fish within the school influences the performance of the group as a whole. Understanding the links between individual and group performance is important since future disturbances to aquatic environments - in response to factors such as pollution or climate change, for instance - may cause changes in the physiology and behaviour of individual fish, and by extension, entire fish schools. The effect of environmental change on animals living in groups has been mostly overlooked, and fish schools are perfectly suited for studying this important aspect of biodiversity. This project will examine these issues by investigating how physiological differences between individual fish may affect their behaviour within a school, and in turn, how these individuals affect the behaviour of the entire school in response to environmental stressors such as increased temperature or decreased oxygen availability. To achieve these goals, this Fellowship will include several laboratory-based studies, and, by using Northern Europe's largest public aquarium (located in Denmark), will also incorporate the first ever scientific observations of individual behaviours in a school containing thousands of fish. Fish schools are ideal for studying the interaction between hysiology and behaviour in animals, a link which has rarely been demonstrated directly. As such, any advances in this subject are likely to result in a range of questions for future research in both ecophysiology and behavioural ecology.