Assessing the recovery of functional diversity after sustained sediment screening at an aggregate dredging site in the North Sea

  • Published source details Barrio-Froján C.R., Cooper K.M., Bremner J., Defew E.C., Wan H.W.M.R. & Paterson D.M. (2011) Assessing the recovery of functional diversity after sustained sediment screening at an aggregate dredging site in the North Sea. Estuarine, Coastal and Shelf Science, 92, 358-366.


This study is summarised as evidence for the following.

Action Category

Cease or prohibit aggregate extraction

Action Link
Subtidal Benthic Invertebrate Conservation
  1. Cease or prohibit aggregate extraction

    A site comparison study in 2004 of seven sites of sandy seabed in the southern North Sea, off the coast of Belgium (Barrio-Frojan et al. 2011) found that 21 months after ceasing aggregate extraction at sites, invertebrate species richness and abundance were similar to that of nearby natural sites where extraction did not occur. Extracted sites had similar number of invertebrate species (16–18/site) compared to natural sites (12–17/site) after 21 months, and in similar abundance (extracted: 700–990 individuals/m2; natural: 480–860 individuals/m2). In February 2003, aggregate extraction ceased in the Kwinte Bank licence area. In November 2004, invertebrates were surveyed at three extracted sites and at four natural sites in the nearby Middelkerke Bank. Five samples/sites were collected using a sediment grab, and invertebrates (>1 mm) were identified and counted.

    (Summarised by: Anaëlle Lemasson)

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