Introduction
Integrated pest mnagement (IPM) is directly concerned with manipulating potentially damaging pest populations and exploits the synergy between control strategies. The drive towards sustainable methods of crop production has demanded that we should minimize chemical use, energy inputs, the effects on non-target organisms, and harm to the wider environment. The development of a framework to conceptualize the processes that drive pest population dynamics will be crucial to this endeavor and allow us to devise increasingly sophisticated, successful, and sustainable management strategies.
Over the last 20 to 30 years there has been a revolution in ecological thinking on how populations function, with the growing appreciation of the spatial dimension and the importance of movement in population dynamics (Woiwod et al., 2001). This revolution found its expression in the development of metapopulation theory, based on the concept of local populations linked together by movement (Hanski, 1999; Hanski and Gilpin, 1997). The metapopulation approach, and indeed the word itself, originated from models developed by Levins (Levins, 1969; Levins, 1970) but this conceptual framework only started to be applied widely in ecology from about 1990 onwards (Hanski and Simberloff, 1997).
The development of this theory has been driven largely by theoretical ecologists and its application by those working within conservation biology. This is perhaps unsurprising as early model formulations emphasized discrete subpopulations with high likelihood of turnover (i.e. extinction and re-colonization) and low levels of movement between patches, which is clearly directly applicable to many species of conservation concern.