Integrated Management of Marine Ecosystems and the Role of Marine Protected Areas Han Lindeboom

The North Sea in 1880 Olsen, Piscatorial Atlas (1883)

Oysters Moorlog Mud, silt Sand Stones

The past = the present=the future

The Common Sole formerly plentiful now very scarce, requires immediate attention for its preservation or propagation. (Olsen, 1883) The sole

More protection needed

Criteria for protection: EU Habitat Directive: Sand banks Reefs, gravel Sub-marine structures, gasseeps Species: sea mammals, fish EU Bird Directive: Species and occurrence of 1% of the population OSPAR Threatened and important species and habitats Ecological importance, High biodiversity, Representatively, vulnerability, naturalness

Sand banks Gravel Data: TNO, RWS

Benthic fauna Data: Royal. NIOZ

Fish Birds Annual mean

Proposed areas with special ecological values (Lindeboom et al., 2005)

Integrated Management plan North Sea areas nominated Existing use will not change

J.Haelters et al. Belgium

J.Haelters et al. Westhinder

Use of the North Sea

Gas- and Oil- platforms

June 2005 June 2007 Great cormorant

New parks ?

Fisheries: bottom trawling

Effects beam trawling Killing target and non-target species Food birds Changing: species age habitats Long term effects ?

Before After

Callianassa Upogebia Quahog Conclusions: Significant difference unfished-fished > shrimps and shelfish > biodiversity Beam trawling causes changes in the fauna, which influences structure, bioturbation and mineralisation. This has large consequences for the functioning of the benthic ecosystem

“Old habitat types” Sand bank Gravel Silt “New habitat types” Ploughed habitat Raked habitat Platforms Wind park Habitat types in the North Sea

Will protection be effective ? Example: the Quahog

Evaluation and targets for the Quahog population Rob Witbaard, IMARES/Royal NIOZ The Frisian Front area has a relatively low abundance of Quahogs (0.06/m2): 20 years ago this was 6 times higher Beam trawl fisheries cause a large additional mortality upon Quahogs Model calculations indicate that the Quahog will basically disappear from the Dutch Shelf in 2017 (Bergman & Sandbrink, 2000) Quahog populations may be genetically different (Holmes, 2003) Climate changes may lead to a change in Quahog distribution To save Quahogs on the Dutch Shelf, fisheries intensities in areas with relative high densities should be strongly reduced What area is most suited to protect Quahogs on the Dutch Shelf ?

C. Röckmann et al. (2007) Nat. Res. Modeling 20 (2):

Fishing as usual Permanent closure Temporal closure Climate change (salinity decrease)

Or real closures ? ?

Conclusions: An integrated approach of protection, harvesting and building is needed for a sustainable North Sea Fisheries is at the limit of the carrying capacity of the ecosystem: big changes are needed The human pressure is rapidly increasing In 1880, >20% of the Dutch North Sea bottom was ‘hard’, now almost everywhere sand and mud MPA’s should be created

Thank you.