The relationships between population dynamics and fishery resources are more complex than the concept of Malthusian overfishing implies. Reasons include changing biophysical characteristics of the upwelling system along the coast of West Africa; changes in fishing effort; the nonlocal market demand for fish; fisheries migration; and institutions regulating fishery resource and economic changes on migration rather than population pressure on fishery resources. Fisheries management policies must therefore take into account processes that lie beyond the influence of local fishermen.