MarBIT (Marine Biotic Index Tool) is an assessment system for macrozoobenthos (benthic invertebrates) of coastal waters.

It was developed for the Landesamt für Landwirtschaft, Umwelt und ländliche Räume (LLUR; en: State Office for Agriculture, Environment and Rural Areas) and the University of Rostock (a project from the Federal Ministry of Education and Research) for the implementation of the Water Framework Directive. For the Baltic Sea, the assessment system is fully developed. The system has also been adapted for use in the North Sea (mussels, Helgoland rocky tidal flats).

The basis of the assessment system is a database with autecological information on many species from the North and the Baltic Sea (e.g. habitat type, zonation, salinity requirements, sediment preferences).

MariLim has developed a software (for Windows, OS X and Linux) implementing the MarBIT assessment system to easily analyse sample data and assess the ecological status of benthic invertebrates.

The research report including all necessary information to use MarBIT, is available as free download (in German only, with a summary in English; PDF file, 10 MB).