News

Models are not religion – it´s ok to cheat

Published on September 17, 2012

Dr. Christensen, the lead developer of both the Ecopath and Ecosim modelling software, widely used for ecosystem-based management of marine systems, held a seminar at the Swedish Royal Academy of Science last Friday.

The seminar began with Dr. Christensen giving a short overview of the use of ecological network theory for fisheries management and continued by describing how ecosystem models have been developed to be used for making predictions.

The main message Dr. Christensen sought to convey with his seminar was that we cannot expect a single model to give all the answers, the models are not sophisticated enough to alone provide accurate answers. Instead, to be able to grasp the complexity of ecosystems, several models should be used to make reliable predictions. Dr. Christensen used his own work to illustrate the need to combine several models, in which he uses three models simultaneously.

Dr. Christensen currently facilitates workshops on Ecopath around the world. One of his core projects for many years is the Sea Around Us Project a “database-driven, ecosystem model construction”, with the aim of usingglobal, spatial databases to parameterise, balance and fit ecosystem models“.

Ecopath is a static, mass-balanced snapshot of the system while Ecosim is a time dynamic simulation module for policy exploration. Both Ecopath and Ecosim have been used when developing the multispecies plan for the Baltic Sea.