More than 10.000 marine species live in the European oceans. But there is no comprehensive pattern of relationship between latitude and marine fauna biodiversity. More coordinated research efforts are needed to fully understand the marine biodiversity and develop proper management mechanisms, according to a recently published paper.

Text: Eva Therese Jenssen

The oceans along the coast of Europe cover vast geographical area, and encompass not just the Arctic Ocean system, but also temperate and even sub-tropical climate zones (from 35º N to 81º N).

These oceans outside the European coastline constitute the home for more than 10.000 marine species (excluding unicellular species). However, although these species live in habitats covering several latitudes, there is no comprehensive pattern of relationship between latitude and marine benthic fauna biodiversity.

Trends in biodiversity

In a new paper published in the open-access journal PLoS ONE; UNIS marine biologists Jørgen Berge and Paul Renaud together with colleagues from Norway, the Netherlands and United Kingdom, report previously unpublished data on changes in species richness and combine published and new biodiversity data from coastal habitats, continental shelves and the deep-sea to provide an overview of what is known along the western European margin.

The authors have compiled and analyzed trends and patterns in biodiversity reported in the scientific literature.

- Identifying mechanisms that are responsible for the establishment and maintenance of biodiversity patterns is one of the most important scientific challenges if we are to manage marine ecosystems and their resources, says Berge.

Within the North Atlantic and Arctic Ocean, the benthic biodiversity does not seem to be correlated with latitude, but depth seems to be more important. (Photo: © Erling Svendsen).

The authors conclude that within the North Atlantic and Arctic Ocean, the benthic biodiversity does not seem to be correlated with latitude, but depth seems to be more important, as species richness generally increases to a depth of 200 m and then decreases to 300-500m along the western European shelf.

Still knowledge gaps

However, a shift in climate to a warmer Arctic environment will result in an increased number of more temperate benthic and pelagic species migrating northwards, especially on the western coasts of Greenland and Svalbard. This will affect marine biodiversity in Arctic regions and might also lead to changes for top predators such as marine mammals and birds.

- There is still knowledge gaps related to large-scale patterns and across habitat boundaries, and our understanding of the marine environment will continue to be limited, unless coordinated multi-national efforts to provide long-time data series can be carried out, Berge explains.

– The value of rare species for marine community robustness and structure is poorly understood, which of course affects our ability to develop proper management mechanisms for marine resources.

The solution is greater coordination between European research programs, especially in standardization of sampling techniques and analysis of data for large-scale spatial and temporal patterns to be fully understood, the authors conclude.

Source:
Narayanaswamy BE, Renaud PE, Duineveld GCA, Berge J, Lavaleye MSS, et al. (2010): Biodiversity Trends along the Western European Margin. PLoS ONE 5(12): e14295. doi:10.1371/journal.pone.0014295

A shift in climate to a warmer Arctic environment will affect marine biodiversity in Arctic regions and might also lead to changes for top predators. (Photo: © Erling Svendsen).