INSITE North Sea

Is there an influence of man-made structures on ecosystem structure and functioning at the scale of the North Sea?

COSM will address this question by developing a spatio-temporally dynamic model of the food web coupled directly with a Geographic Information System (GIS). In this way, spatial information on habitat type (substrates and bathymetry), environment (temperature, salinity, stratification, primary production) and pressure data (fishing) will be used to model the distribution of benthic and pelagic ecosystem components from infauna to seabirds.

Consumption of prey (e.g. benthic fauna) by functional groups (e.g. benthivorous fish) will be modelled in relation to their habitats and the subsequent flow of this mass through the system to higher predators (i.e. piscivorous fish, mammals and seabirds) will be examined. The foundation for this will be a published calibrated model, quality controlled in accordance with guidance by the International Council for the Exploration of the Sea. The resolution of the model will be tailored to the finest scale possible that is appropriate based on the resolution of data and the scenarios required to address specific questions.

Man-made structures will be considered in terms of additional habitat for benthic fauna and thus additional foraging areas for predators and as potential corridors and stepping stones linking biological assemblages.

Once calibrated using the available data, the model will be used to predict the effect of including or excluding man-made structures in terms of the consumption and biomass of predatory groups. The natural variability of the ecosystem will be characterised to contrast any effect of man-made structures by driving the model with a series of maps of environmental variables and primary production. Any effect of man-made structures would then be compared to the effect of other pressures (e.g. fishing) in order to put this on context.

The study will generate hypotheses and identify what potential data gaps are necessary to fill in order to improve our understanding and prediction of the dynamics of the North Sea ecosystem and its sensitivity to pressure. As an ‘experimental tank’ the model will help serve to make available mutually compatible data on the ecosystem, while at the same time expose weaknesses and uncertainties in data and knowledge necessary to address in future. Additional data collection in the next stages of INSITE would allow for further model validation and improvement, particularly in relation to habitat dependencies and movement patterns of fauna. COSM will develop and publish applied modelling tools that will benefit the scientific community and improve our knowledge of those food web interactions that are fundamental to ecosystem functioning.