, Volume 39, Issue 7, pp 476–485 | Cite as

Assessment of Blue Mussel Mytilus edulis Fisheries and Waterbird Shellfish-predator Management in the Danish Wadden Sea

  • Karsten Laursen
  • Per Sand Kristensen
  • Preben Clausen


We assessed the blue mussel Mytilus edulis fishery management scheme introduced in 1994 in the Danish Wadden Sea that regulate fishing vessels, fishery quota, set-aside for mussel-eating birds and established zones closed to mussel fishery. The results showed (i) a reduction in the blue mussel biomass and mussel bed areas in zones closed to fishery, (ii) decrease in eiders Somateria mollissima numbers and increase or stable numbers for oystercatcher Haematopus ostralegus and herring gull Larus argentatus and (iii) that energy estimations based on ecological food requirements for the mussel-eating birds should be at least three times larger, than the amount set-aside in the mussel management scheme. It is concluded that the mussel management scheme had been unable to stabilize or increase the blue mussel stocks and to secure stable or increasing numbers for all target bird species. Thus, it is recommended to revise the present blue mussel management scheme in the Danish Wadden Sea, to continue and improve mussel stock and bird surveys, and to consider novel studies of the mussel-eating birds’ energetics for improved set-aside estimates and future assessments.


Biomass Ecological food demand Eider Favourable conservation status Herring gull Natura-2000 Oystercatcher Wadden Sea 



We are greatly thankful to Bruno Ens, SOVON, for suggestions to a former draft, to Tony Fox, NERI, for his valuable comments and assistance in this manuscript, and to John Frikke, Miljøcenter Ribe, the Ministry of the Environment, for making a considerable number of the aerial surveys used in this article.


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Copyright information

© Royal Swedish Academy of Sciences 2010

Authors and Affiliations

  • Karsten Laursen
    • 1
  • Per Sand Kristensen
    • 2
  • Preben Clausen
    • 1
  1. 1.National Environmental Research Institute, Department of Wildlife Ecology and BiodiversityUniversity of AarhusRøndeDenmark
  2. 2.DTU-Aqua, Section for Coastal EcologyTechnical University of DenmarkCharlottenlundDenmark

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