How Many Biotopes Fit into One Sea?

 

Developing a common classification for Baltic Sea habitats and biotopes that is pragmatic and shared by all Baltic Sea countries, has been a particular challenge. The HELCOM RED LIST Biotope project started compiling a Red List of endangered Baltic Sea habitats and biotopes in 2009, but quickly realized that it is hard to assess something if you do not know what is there. This was the beginning of the extensive and ambitious process to create a biologically meaningful Baltic Sea-wide classification of habitats and biotopes based on data collected around the Baltic Sea and one that is compatible with the European Nature Information System (EUNIS).

 

This HELCOM project received funding from the Nordic Council of Ministers and has since utilized a two-fold strategy to quickly and reliably achieve the required results, while allowing for the effective and transparent participation of national experts.

 

The bulk of the background work - data acquisition and analysis as well as biotope descriptions - has been carried out by expert consultants, while the actual designation and grouping of the biotopes has been done collectively by national experts over five workshops to date. Drawing up the classification has involved much deliberation and patience by the dedicated expert team as opinions and views frequently changed! Now, however, we are almost there.

 

The classification will be hierarchical and contain six levels - Level 1 being the Baltic Sea and Level 6 biotope types defined by dominating species and community. Each level is divided into a number of classes which, in turn, are defined by the parameters available at that level. Since the system is hierarchical, the number of classes increases as you move further away from Level 1, rather like a tree where Level 1 is the trunk. A schematic of how the classification is constructed is shown in Figure 1.

The levels can be found in Figure 2. The current draft contains more than 90 classes at Level 5 and more than 180 classes at Level 6. Clear descriptions will be provided for all the classes and the main outcomes - the classification system and the biotope descriptions - will be published in the Baltic Marine Environment Proceedings series of HELCOM and on the HELCOM website.

 

Has this been done before?

 

The first commonly agreed Baltic Sea biotope classification was the HELCOM Red List of marine and coastal biotopes, and biotope complexes of the Baltic Sea, Belt and Kattegat (HELCOM 1998). This provided the classification and descriptions of Baltic Sea biotopes defined mainly by substrate and depth zone. The biotopes from this HELCOM Red List were integrated into the European Nature Information System (EUNIS) habitat type classification, which covers all habitats from marine to terrestrial environments.

 

EUNIS classifies habitats according to the characterizing elements of the biotic environment (e.g. dominant species) and a set of abiotic factors that are important drivers of community composition. The classes are arranged hierarchically, where the upper levels are mainly identified by abiotic factors (down to Level 3) and the lower levels are described by a combination of biotic and abiotic descriptors. More information on EUNIS can be found at: http://eunis.eea.europa.eu/about.jsp. 

n

 

 More recently, it was realized that the EUNIS classification adapted to the Baltic Sea contained only little biological information, such as on species. At the same time, progress had been made in national and international projects in the Baltic Sea countries in producing more detailed, biology-driven habitat classifications for sub-regional and local areas of the sea.

 

In 2009-2010, it was possible to further develop the EUNIS-compatible classification of Baltic Sea biotopes with the EUSeaMap project, funded by the European Commission. The project produced broad-scale habitat maps for the Celtic, North, Baltic and Mediterranean Seas. The Baltic Sea part of the project utilized both new data on marine species and biotopes as well as new sub-regional classification proposals; however, it still did not go below Level 4, meaning that it did not include any information on living things.

 

The 2007 Baltic Sea Action Plan promoted the updating of a complete classification system for Baltic marine habitats and biotopes. In 2010, the HELCOM Red List project continued to build on the results of the EU SeaMap project. The project aims to extend the classification up to Levels 5 and 6, and to arrive at a biologically meaningful classification that can also be used for management purposes.

 

Why do we need a classification?

 

The classification of Baltic Sea habitats/biotopes will facilitate

spatial planning, as well as the underlying pragmatic mapping activities of underwater biodiversity. The results of the project will also assist EU member states to implement the EU Marine Strategy Framework Directive and make the information comparable between the countries that use the classification. One of the descriptors of good environmental status of Annex III of the Directive addresses biological diversity, habitats in particular; the EU member states will thus be required to develop targets and associated indicators reflecting biodiversity.

 

The Directive also requires countries sharing a marine region to cooperate and coordinate their activities. The Red List project facilitates the harmonized and coordinated implementation of the Directive as far as it concerns the habitats/biotopes of the Baltic Sea. In addition, the EU is increasingly laying out measures related to maritime spatial planning, such as the European Commission’s roadmap for maritime spatial planning under the EU Maritime Policy.

 

Who benefits from using the classification?

 

Using the classification will facilitate the work of the marine environment authorities of the Baltic Sea countries; those implementing the HELCOM Baltic Sea Action Plan; the EU Strategy for the Baltic Sea Region and Marine Strategy Framework Directive; and those responsible for maritime spatial planning and who work internationally with issues related to habitats and biotopes.

 

When will it be available?

 

The classification system, the report and the descriptions of all biotopes will be published in 2013 and will be made available electronically on the HELCOM webpage under ‘Publications’.