Lifeco is a multidisciplinary research programme designed to resolve the influence of tidal mixing and shelf breakfronts on the recruitment success of North Sea fish stocks, and thereby develop environmentally sensitive recruitment models. To do so, Lifeco will integrate results from a 3D coupled biophysical model, remote sensing and field programmes and historic databases. Integration will be provided via GIS to test the hypothesis that variations in frontal activity influence the recruitment of commercial fish stocks via bottom-up and top-down processes acting on the young of the year. Furthermore, the programme will resolve the importance of hydrographic processes on spatial distribution and feeding interactions of commercial fish stocks, a result of importance for assessment and management strategies. Finally, the identification of unique ecological enclaves will aid in the development of management strategies based on environmentally sensitive areas.
The objectives of this research programme are:
1) to improve the scientific basis of fishery management by improving the knowledge used in stock development predictions and more general assessment tools via resolution of the importance of frontal mixing processes for the recruitment dynamics of commercial fish stocks in the North Sea
2) to contribute to the improvement of stock assessment methods by identifying uncertainties in the stock assessment programmes presently employed. Here the programme will identify if a need exists to adapt the surveys assessing stock abundance to be able to examine abundance relative to hydrographic features
3) to examine the concept of prey suitability for predators as presently implemented in multi-species assessment models. At present, models assume constant suitability and selection of a specific prey species by a given predator regardless of prey availability - an assumption that may be influenced by hydrography
4) to identify ecological regimes that act to influence ecosystem dynamics. This identification of unique ecological enclaves will allow the development of management strategies based on environmentally distinct and sensitive regions, and thereby identify potential areas for ecological reserves or for the development of area-specific management strategies.
As the programme focuses on a key hydrographic feature influencing ecosystem dynamics, and examines how the process varies relative to climatic forcing, it has the potential to contribute significantly to our understanding of the potential influence of climate change on the North Sea ecosystem.
1) A time series of stratification intensity from the 3D 10 km grid HAMSOM hydrodynamic model has been developed for comparison with frontal activity.
2) A 1D coupled biophysical model has been developed to examine historic variations in the timing of the spring and autumn phytoplankton blooms, as well as zooplankton production.
3) Near real-time remote sensing has been supplied to ships at sea during the field programme, and remote sensing has been supplied to validate the 1D modelling exercises.
4) The field phase is complete and has assembled physical and environmental data, and preliminary data on fish distribution and abundance.
5) The modelling of prey preference, consumption rates and trophic interactions has begun as planned.
6) Preliminary diet composition data from the field phase are available.
7) The working physical/environmental database structures have been developed and are suitable for the transformation of data to GIS raster grids. A functioning plankton/fish database structure is operational and the transformation of spatial information to GIS raster grids made possible. Furthermore, data import and request programmes to the databases, including user manuals, have been produced.
8) A GIS database design has been based on pilot cruise results and biological and hydrographic database design. A suite of display tools for easy data viewing was produced.
9) Ongoing analysis in Work Package 9 demonstrates that the results of the programme will probably be of significant benefit for the management of fisheries.
FISHERIES AND AQUACULTURE, QUANTITATIVE APPROACHES AND MODELLING
Scientist responsible for the project
Chief Scientist HELGE ABILDHAUGE THOMSEN
Denmark - DK
Phone: +45 3396 3400
Fax: +45 3396 3434
||Danish Institute for Fisheries Research
||01 October 2000
||4 385 696 €
|Total EC contribution
||1 900 000 €