To aid in fish management, we can assess stocks by using a combination of three methods ("World Fisheries," 2006):

Other metrics include the Ecosystem Services (ES) Model originally developed by the Millennium Ecosystem Assessment (MEA) in 2005 , which although developed for terrestrial environments, has not been fully researched for marine ecosystems. The concept of Ecosystem Services is that processes and functions provided by ecosystems benefit human activities and that the services that these ecosystems provide can be economically and socially analyzed to determine how ecosystems should be preserved to support resources required by humanity. The MEA has created a classification to organize the assessment of ESs according to the type of service being provided by a particular ecosystem. However, much more research is necessary before this system can be adequately adapted to reflect the status of marine environments (Cognetti & Maltagliati, 2010).