Advancing Multi-Species Management: An Economic Perspective

Fisheries economists have pursued a variety of methods to capture multi-species and ecosystem approaches to fisheries management that go beyond the naïve approach of simply multiplying outputs from a biological model by prices. One approach has been to incorporate economics into structural population dynamic interactions, the bio-economic modeling approach. A related approach is to include economic models as part of a larger ecosystem modeling approach as has been done with, for example, Ecopath w/Ecosim or the Atlantis model. The advantage of these approaches is that they capture behavior of economic agents which can greatly influence the ultimate model output. Abstracting away from the structural approaches, portfolio analysis builds upon the statistical relationships within the system so that the researcher is not necessarily able to explain the mechanisms of the interactions, but has a tool to predict what the outcome of the interactions will be. This latter approach works best when predictions are within sample observations, so it might not be as useful for large scale ecosystem shifts that might occur due to climate change or the recovery of an ecosystem from eutrophic conditions.