Spawner weight and ocean temperature drive Allee effect dynamics in Atlantic cod, Gadus morhua : inherent and emergent density regulation

Stocks of Atlantic cod, Gadus morhua, show diverse recovery responses when fishing pressure is relieved. The expected outcome of reduced fishing pressure is that the population regains its size. However, there are also cod stocks that seem to be locked in a state of low abundance from which population growth does not occur (or only slowly occurs). A plausible explanation for this phenomenon can be provided by the Allee effect, which takes place when recruitment per capita is positively related to population density or abundance. However, because of methodological limitations and data constraints, such a phenomenon is often perceived as being rare or non-existent in marine fish.