Modelling dynamic ecosystems: venturing beyond boundaries with the Ecopath approach

Abstract

Thirty years of progress using the Ecopath with Ecosim (EwE) approach in different fields such as ecosystem impacts of fishing and climate change, emergent ecosystem dynamics, ecosystem-based management, and marine conservation and spatial planning were showcased November 2014 at the conference ''Ecopath 30 years-modelling dynamic ecosystems: beyond boundaries with EwE''. Exciting new developments include temporal-spatial and endto-end modelling, as well as novel applications to environmental impact analyses, in both aquatic and terrestrial domains. A wide range of plug-ins have been added to extend the diagnostic capabilities of EwE, and the scientific community is applying EwE to a diversified range of topics besides fishing impact assessments, such as the development of scientific advice for management, the analysis of conservation issues, and the evaluation of cumulative impacts of environmental and human activities in marine food webs (including habitat modification and the invasion of alien species). Especially promising is the new potential to include the EwE model in integrated assessments with other models such as those related to climate change research. However, there are still many challenges, including the communication of scientific results in management procedures. In addition, other M. Coll (

A protocol for the intercomparison of marine fishery and ecosystem models: Fish-MIP v1.0

“…Ecopath with Ecosim (EwE), one of the oldest and most widely used marine ecosystem modelling approaches (Christensen and Walters, 2004), focuses explicitly on trophodynamics, as does its global offshoot EcoOcean (Christensen et al, 2015).…”

“…More recent applications include cumulative 15 human impacts, marine conservation, environmental impact assessments and end-to-end modelling (Coll et al, 2015). EwE models typically include demersal and pelagic species from primary producers up to top predators, both commercial and non-commercial.…”

“…Ecospace, the spatial-temporal model run in Ecospace in conjunction with the food web and fisheries dynamics components, has been further developed to be able to spatially derive the foraging capacity of individual species from physical, oceanographic, and environmental drivers such as depth, temperature bottom type, oxygen concentrations and 20 primary production (Christensen et al, 2014). This development, in combination with the recently added spatial-temporal framework module (Steenbeek et al, 2013), has bridged the gap between environmental envelope models and food web models (Christensen et al, 2014(Christensen et al, , 2015. EwE models are typically structured by species or functional groups, and can also include age-or size-based representation of species.…”

“…As examples of approaches taken by individual Fish-MIP models, the EcoOcean model applies fishing as an effort term based on the Sea Around Us Project (SAUP) effort database (Anticamara et al, 2011;Christensen et al, 2015;Watson et al, 2013); the DBEM model uses an alternate catch reconstruction database (Watson, 2017); BOATS has a dynamic 20 bioeconomic approach using SAUP catch price data to simulate spatially-resolved changes in fishing effort over time, based on individual fishers attempting to optimize their outcomes ; SS-DBEM represents maximum sustainable yield without explicitly calculating fishing mortality (Fernandes et al, , 2017Mullon et al, 2016), using SAUP data supplemented by other sources (the ICES data collections (www.ices.dk/marine-data/datasetcollections/Pages/Fish-catch-and-stock-assessment.aspx) and the RAM legacy stock assessment database 25 (www.ramlegacy.org)). This last example further demonstrates how fishing impacts may be modelled implictly.…”

Quantitative vs. Semiquantitative Ecosystem Models: Comparing Alternate Representations of an Estuarine Ecosystem

“…By incorporating a wide range of important biotic and abiotic variables, multitrophic-level quantitative models are able to replicate historic changes in natural resources of interest. A ''fitted'' model (one compared with known data) can then be used to provide formal management advice (Fulton, Smith, and Smith, 2007), investigate the broad-scale effects of different management strategies (Christensen, 2013), understand how ecosystem evolution interacts with adaptive management strategies (Coll et al, 2015), and identify research needs by highlighting data gaps or areas of high uncertainty (Christensen and Walters, 2004).…”