Objectives The overall objective is to establish a large-scale network of research locations/sites along the European coast to assess long-term changes in biodiversity and their possible causes taking into account natural and anthropogenic gradients. Description of work Task 1: Set-up of a chain of research locations/sites along the European coast for the observation and comparison of long-term biodiversity patterns. The research sites should be located along and at intersections of longitudinal and latitudinal biotic and abiotic gradients (e.g. temperature, salinity, trophic environment). Accordingly, based on already existing data sets trends noted at one location can be compared with others. Replicate sites should be nested within regions wherever possible to separate local from regional and global change and to quantify variability at different spatial scales. Task 2: Identify specific data-sets Long-term datasets available will be located and set up for comparison of sites. To this aim, a preparatory workshop is already scheduled at Helgoland in 03-06 March 2005 (subsequent to a phytoplankton data ñ workshop by ESF). This will be co-funded by AWI and MarBEF seed money. Participants to the workshop will discuss and decide on the following: Which types of data sets are required to fulfil the objectives of this study? Which are the most appropriate univariate and multivariate analytical techniques to use? What are candidate response variables to use in analyses? Which data are available within the MARBEF community? A central workshop will be defined which is planned for Mid 2006 at Plymouth. Both will be planned and conducted in close coordination with Theme1, key area 1.7 Data archaeology and a further Responsive Mode Project with that topic, headed by VLIZ (E Vanden Berghe). The Topic of the Plymouth Central Workshop will be on Data Networking. Task 3: Review and apply methods and tools Review state of the art concerning methods to monitor and track long-term, large-scale changes in biodiversity. Application and further development of a set of agreed univariate and multivariate methodologies using available data sets. Development of cost-efficient sampling designs for longterm, large-scale analyses of biodiversity. Employ specific indicators and tools to exam anthropogenic impacts on biodiversity. As starting point for this task a workshop is planned (core programme activity) for February 2005 at Banyuls. Review existing knowledge regarding appropriate methods and indicator species considering BIOMARE results Set up a metadata base on manual/protocols of agreed methodology. Based on results of this workshop the focus within this task will be on: Statistical re-assessment (Analysis) of already available data Comparison of MARBEF LTBR locations, with different degree in diversity and/or anthropogenic impacts, to test various methodologies Interactions with RMP 6 on spatial scales of genetic diversity. This will include a comparative analysis to determine the extent to which spatial scales in community data match those of genetic diversity Development of guidelines and rapid assessment tools (e.g. GIS maps, use of remote sensing) for practical applications and managers, using expertise from MarBEF partners and external experts Task 4: Propose comparative experimentation Scenarios will be identified in relation to hydroclimatic change. One experimental set-up may then be conducted at one site on a set of species adopting environmental conditions of a set of comparative sites (making use of facilities from the different MarBEF partners involved). The objective will be to identify possible effects of environmental changes on a set of key species and consequences to their changing roles in community structure and finally in food-webs on an European scale. Experience and results from other Responsive Mode Projects of MarBEF following similar lines may already be integrated at a later stage of the project. Pilot studies may then be established through a later proposal to MarBEF or post-MarBEF or external funding. Task 5: Extend to biogeographic scale The partners named so far (further additions are urgently invited!) represent larger bio-geographical areas. In addition, their sites have been identified by the EU concerted Action BIOMARE in a graded system of reference sites for biodiversity studies. However, their geographic position may further serve as a focal point to facilitate access to the research and results of further marine institutes in the same region. In this way the partnerís institutes may help in propagating the aims of MarBEF further, in collating data and in experimentation from/at these institutions in their vicinity, where many have also been pre-selected by BIOMARE. This approach bears the potential, that beyond the formal end of the MarBEF-NoE, a system of sites may stay available to large scale comparative work on biodiversity and ecosystem function.