ABSTRACT
Umeå, Sweden 901 83. E-mail: Carin.Magnhagen@slu.se 3 Dept. of Biological Sciences, 4401 University Drive, University of Lethbridge, Lethbridge, Alberta,
Canada T1K 3M4. E-mail: gregory.pyle@uleth.ca *Corresponding author
Fish are by far the vertebrate group with the most strikingly diverse repertoire of behaviours and behavioural adaptations. As such, their study provides a fascinating insight into the complexities of animal behaviour. Percids are no exception, seemingly rife with contradictions in their behaviours. From active dispersers to spawning-site homers, cannibals to prey, strong competitors as consumers to weaker ones as top predators, facultative shoalers to solitary predators, and from risk-averse to risk-prone phenotypes, perch have a varied collection of behaviours that enable them to facilitate their occupancy and adaptation to a myriad of habitats across a wide geographical range. Their behaviours furthermore infl uence the population dynamics of their predators, prey, and competitors; and equally, the ecological context in which perch are found shapes their behavioural repertoire. In terms of species differentiation, European (Perca fl uviatilis) and yellow (P. fl avescens) perch are overwhelmingly similar. The same abiotic and biotic effects limit distributions and growth capacities of both species, and they occupy comparable trophic positions. As a result, they display a similar suite of parallel behaviours, and can be considered behaviourally equivalent. The following chapter reviews both European and yellow perch behaviour in terms of their habitat selection movements, competitive abilities, antipredator strategies and conversely, their impacts as predators, and lastly, their social behaviours. Although presented individually in sub-sections within the chapter, each type of behaviour cannot be considered without acknowledging the interacting drivers, both biotic and abiotic, that shape the adaptive behaviours of perch in their attempts to maximize lifetime fi tness. The unifying theme throughout this chapter, therefore, is that the adaptiveness of each element of perch behaviour must be considered in the context of the genetic predisposition, and how individuals make tradeoffs within and between the competitive environment, predation pressure, life history changes, and habitat suitability. Each section of this chapter therefore discusses specifi c behaviours of perch within this framework. The chapter ends by demonstrating how knowledge of perch behaviour can contribute to how individuals will fare in their responses to cumulative effects of multiple stressors in today’s changing environments.
