A global team of marine biologists has recently completed a Census of Marine Life, which contributes to our basic understanding of marine ecosystems. Among its findings, marine biodiversity in the Baltic and Mediterranean seas are among the globally most threatened ones.
Although biodiversity is central to the European Commission's vision of sustainable development, detailed ecosystem knowledge and a continuous programme of measurement and reassessment is still required to understand exactly what it means.
A recent paper highlights the key findings of the Census of Marine Life, which ran for 10 years (2000-2010), involving over 2700 marine biologists from 80 countries. So far, 1200 new species have been recorded worldwide, with many more expected.
The paper provides some statistics relating to biodiversity, including species richness (the number of different species observed) and endemic (species found only locally) or alien species counts. It also monitors the availability of biodiversity expertise and defines an index representing 'the state of knowledge' - therefore measuring both biodiversity and our ability to make and evaluate such measurements.
European results are reported for Atlantic, Baltic and Mediterranean seas. The state of knowledge in Europe is high, with many experts, published guides, laboratories and vessels. However, the deep Mediterranean is the exception, where 75 % of species were estimated to be undescribed.
Baltic and Mediterranean biodiversity were found to be amongst the most threatened globally. The three main threats for the world as a whole were overfishing, habitat loss and pollution and climate change. In the Mediterranean, aquaculture and maritime traffic are also significant. The Mediterranean suffered the highest number of reported alien species (over 600, or 4 % of all species found there) in the world, whilst the Baltic and Atlantic European regions also contained high numbers of alien species (2 %).
Crustacean, mollusc and fish species accounted for around 50 % of species richness globally and are also amongst the groups about which we know the most. Less numerous (or physically smaller) groups, such as sponges, corals, jellyfish, bacteria and other micro-organisms are less well understood, with fewer experts available to identify them.
Noting declining numbers of experts generally, the study suggests that international collaboration is required to distribute expertise appropriately and drive advances elsewhere. It also found that there are few incentives for researchers to publish taxonomic guides, which classify species. Most guides are published as books and not in journals, so do not contribute to citation records which are important to a researcher's career.
The study recommends changes in scientific citation and academic funding to encourage publication in free, online resources (calling this 'the most valuable service taxonomists can provide').
Finally, having identified major gaps in basic knowledge about marine biodiversity, they state that science and society would benefit from another decade of such discovery. Discovery efforts should apply equally to all forms of biodiversity.
Source: Costello, M.J., Coll, M., Danovaro, R., Halpin, P., et al. (2010). A census of marine biodiversity knowledge, resources and future challenges. PLoS ONE. 5(8): e12110.