Diffuse Effects in Food Webs

In order to explore the extent to which interactions between pairs of species embedded in complex multispecies food webs are nonlocalized, in terms of the number of other species that need to be taken into account, the influence of other species in the system on the response of the hake fishery to a cull of fur seals is calculated in a 29-species food web for the Benguela ecosystem. Parameters are assigned biologically plausible values, partly through energetic and allometric reasoning. It is found that behaviorally mediated effects within the multispecies functional response can produce a highly diffuse response.