EFI+ is a research project designed to gain new knowledge and to further develop and improve new biological assessment methods to meet needs of the Water Framework Directive (WFD). The output of the project will be a methodological approach to assess the ecological status of rivers in accordance with the WFD. Therefore the EFI+ project represents a direct and important contribution to the Water Framework Directive in further development and implementation of harmonised fish-based assessment tools and methodology that can be used as a standard method in EU Member States, as well as Candidate countries.

Between 2001 and 2004 the EC-funded FAME project aimed at development, evaluation and implementation of standardised fish-based methods to assess the ecological status of running waters in Europe (FP5, Energy, Environment and Sustainable Management. Key Action 1: Sustainable Management and Quality of Water, EVK1 -CT-2001-00094, http://fame.boku.ac.at). The main output of FAME was the European Fish Index (EFI), the first standardised fish-based assessment method applicable across a wide range of European rivers. The EFI employs a number of environmental descriptors to predict biological reference conditions and quantifies the deviation from reference conditions on a statistical basis. The EFI was developed for Western and Northern Europe and calibrated against a rough estimate of human pressure status. Although a wide range of river types was included in the development of the EFI, very large rivers were underrepresented. EFI is now used and tested in several European countries within the national monitoring programmes of the WFD.

The overall objective of EFI+ is to overcome existing limitations of the EFI by developing a new, more accurate and pan-European fish index. The scientific and technological objectives are to
(1) evaluate the applicability of the existing EFI and make necessary improvements to the existing EFI in Central-Eastern Europe and Mediterranean ecoregions,
(2) extend the scope of the existing EFI to cover very large rivers,
(3) analyse relationships between hydromorphological pressures (incl. continuity) and fish assemblages to increase the accuracy of the EFI,
(4) adapt existing software to the requirements of the new EFI to allow calculation of the ecological status for running waters,
(5) implement and disseminate the EFI and supporting software by integration of the project results in the CIS activities (Common Implementation Strategy) and ongoing national and international monitoring programmes such as the Joint Danube Survey and to present results in end-user workshops and an international conference.