|Institution:||Universiteit van Amsterdam|
|Full text PDF:||http://hdl.handle.net/11245/1.527892|
Seasonality strongly affects ecological dynamics, especially in the temperate zone. In most animal populations, ontogenetic development results in large differences in body size and ecological role between individuals. Individuals in different ontogenetic life stages are therefore differentially affected by seasonality. Yet, the effect of seasonality has been little explored in models that incorporate ontogenetic development. This thesis investigates the importance of seasonality for predictions regarding commercial exploitation and species interactions in biological communities using newly derived and recently developed models that incorporate ontogenetic structure. Existing ecological theory that is based on models with ontogenetic structure and continuous dynamics is shown to be robust against seasonal variability. This thesis furthermore describes effects of seasonality and harvesting on multispecies systems that differ fundamentally from classic insights derived from models that ignore ontogenetic development. The results show that harvesting of prey fish may have a beneficial effect on large predatory fish and that seasonality may promote the persistence of predatory species.