Anchovy biomass is linked to annual potential new production in the southern Benguela: support for the “Optimal environmental window” hypothesis
AbstractThe hypothesis that physical forcing is related to tertiary production was tested by relating regional estimates of annual potential new production to certain pelagic fishery variables. The results show strong evidence of a
dome-shaped relationship between annual potential new production (x-axis) and anchovy spawner biomass (y-axis), providing further confirmation that both a paucity and surfeit of upwelling is detrimental to the fishery.
Fish biomass was maximized by a median range of upwelling, which formed an “Optimal Environmental Window” either side of the dome apex. The relationship was described by a Gaussian Area curve: