the "metapopulation" concept. The metapopulation concept was introduced in 1969: "as a population of populations which go extinct locally and recolonize." Metapopulation ecology is a simplified model of the landscape into patches of varying levels of quality. Patches are either occupied or they are not. Migrants moving among the patches are structured into metapopulations either as sources or sinks. Source patches are productive sites that generate a seasonal supply of migrants to other patch locations. Sink patches are unproductive sites that only receive migrants. In metapopulation terminology there are emigrants (individuals that leave a patch) and immigrants (individuals that move into a patch). Metapopulation models examine patch dynamics over time to answer questions about spatial and demographic ecology. An important concept in metapopulation ecology is the rescue effect, where small patches of lower quality (i.e., sinks) are maintained by a seasonal influx of new immigrants. Metapopulation structure evolves from year to year, where some patches are sinks, such as dry years, and become sources when conditions are more favorable. Ecologists utilize a mixture of computer models and field studies to explain metapopulation structure. Journals The first journal publication of the Society of Population Ecology, titled Population Ecology (originally called Researches on Population Ecology) was released in 1952. Scientific articles on population ecology can also be found in the Journal of Animal Ecology, Oikos and other journals. See also Density-dependent inhibition Ecological overshoot Irruptive growth Lists of organisms by population Overpopulation Population density Population distribution Population dynamics Population dynamics of fisheries Population genetics Population growth Theoretical ecology References Further reading Bibliography Applied statistics Ecology