Marine biological valuation - conclusions from a workshop

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This article provides links to some of the articles derived from a workshop on marine biological evaluation.

Workshop - conclusions

As part of the Encora project a workshop was held on marine biological valuation, from 6 to 8 December 2006 at Ghent (Belgium). The workshop was a joint venture of the EU CA ENCORA ( and the EU NoE MARBEF ( Both Theme 7 within ENCORA and Theme 3 within MARBEF deal with marine/coastal biological valuation and the workshop aimed to reach a consensus on this topic. This considered the concept of marine biological diversity evaluation in some detail. This article provides a summary of the main conclusions from the workshop. The workshop report can be downloaded at ( The key conclusions derived from the report are as follows:

  • As we are assessing the value of biodiversity elements in a study area, the general term ‘marine biological valuation’ should be changed into ‘marine biodiversity valuation’ or ‘marine ecological valuation’.
  • The concept of marine biodiversity valuation, as described in the paper of Derous et al. (2007) was changed as one criterion was excluded (naturalness) from the framework and other criteria were lumped together (aggregation-fitness consequences) or used in a different way (proportional importance).
Derous Figure1 new.jpg
  • Only two valuation criteria are remaining (rarity and aggregation-fitness consequences) and these criteria are applied on the elements of biodiversity.
  • The former “modifying” criterion ‘proportional importance’, which is related with the scale of the study area, is excluded as a criterion, but the scale issue is still present in the concept as the valuation of a study area should be done at two scale: first on a local scale (= scale of the study area) and afterwards on a broader (ecoregional) scale. This will allow evaluating the subareas’ values in a broader perspective.
  • The flowchart on the right illustrates the revised concept for marine biodiversity valuation.
  • The protocol for marine biodiversity valuation should be as transparent as possible and should determine clear assessment questions around the selected valuation criteria and elements of biodiversity. Marine biological valuation should not be done solely by using expert judgement, as consulting a team of experts cannot guarantee the inclusion of subjectivity in the process. Expert judgement could also obscure the valuation process which would make it unrepeatable in the future.
State of the art.jpg
  • The marine biological valuation protocol that will be determined and used in ENCORA Theme 7 and MARBEF Theme 3 will move beyond the use of expert judgement, but will define appropriate assessment questions around the developed concept and test these on real case study areas. Using the assessment questions for valuation could reveal new problems with the concept which demand adaptations. When good assessment questions are determined these can be translated into practical algorithms. However, no mathematical algorithms to apply these assessment questions on databases can be described by the protocol as these algorithms will be different for different study areas as they depend strongly on the available data. So, it is utopic to think that all subjectivity can be banned from the protocol as experts will be asked to determine these algorithms. The ultimate goal of marine biodiversity valuation is to determine well-defined algorithms that produce the same maps independently of the person who applies them to a certain database. But this situation is still far from reality. The figure on the right gives an overview of different approaches for marine biological valuation and the state of the art.
  • Although the protocol is not perfect yet (cannot exclude all subjectivity as expert judgment is still involved), it should be tested as it stands now on case study areas. The results of the valuation of these case study areas will give an idea on the degree of subjectivity involved in the selection of the algorithms by the experts of the different study areas.