Estimation of Primary Production for Fisheries Management

The UN Food and Agricultural Organisation (FAO) reports that worldwide fisheries reached peak level of production in 1994. However, during the last decades a series of fish stocks have reached, or are close to, collapse in several parts of the world. The future viability of fisheries depends upon more complete understanding and monitoring of the interrelation and dependence of ecological and socio-economic factors related to the fisheries activities and exploitation of the marine food resources.
In 1997 the European Commission started an activity related to the development and distribution of the Ecopath-with-Ecosim food chain model – EwE). This project included model development and validation through close interaction, use and validation by a worldwide group of experts from 20 nations. In the fisheries community, the EwE tools are used for studying and simulating marine trophic webs and mass balance, and for ecosystem management. The European Commission funded Estimation of Primary Production for Fisheries Management (PROOF) project has produced estimates of European regional and ocean-basin scale marine phytoplankton primary production (PP) based on available ocean colour and temperature data from earth observation satellites for the period September 1997 to December 2002. A number of models were implemented and tested against archived and extensive project-specific in situ primary production estimates off the northwest of Spain, in the Celtic Sea, English Channel and in the Atlantic Ocean. The seasonal capabilities of the models were tested through a weekly sampling campaign in the western English Channel in 2001; the spatial characteristics used data obtained on a cruise between the UK and South Africa that covered a variety of trophic levels. The opportunity was taken to compare the PROOF model with a variety of models operated by leaders in the field within the NASA PPARR3 project. The sensitivity of the models has also been investigated. The spatial and temporal variability of the PP have been assessed and validated against state-of- the-art marine ecosystem models, based on the MICOM and HYCOM ocean circulation models.
Based on the requirements for the use of PROOF results in food-chain modelling such as EwE, the PROOF project selected and validated the algorithms to be used for production of results based on satellite Earth observation data and model output. The PP estimates and modelled parameters from the PROOF project have been prepared for use in the EwE marine food web model in order to assess the marine production at various levels in the food web. The data are also available via a web site with simple data extraction tools. Finally, recommendations for model improvement and directions for future research are suggested.