Most freshwater ecosystems in the United States are in a state of collapse. Existing management efforts take a piecemeal approach, addressing individual stressors, managing the systems for individual benefits, and protecting individual species. These disjointed efforts are doomed to fail. Both...

Ecosystem Management requires models that can link the ecosystem level to the operation level. This link can be created by an ecosystem production model. Because the function of the individual fish in the marine ecosystem, seen in trophic context, is closely related to its size, the model groups...