Macrobenthos characteristics and distribution, following intensive sand extraction from a subtidal sandbank

Published source details Bonne W. (2010) Macrobenthos characteristics and distribution, following intensive sand extraction from a subtidal sandbank. Journal of Coastal Research, 10.
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This study is summarised as evidence for the following.

	Action	Category
	Cease or prohibit aggregate extraction Action Link

Cease or prohibit aggregate extraction

A site comparison study in 2001–2004 of four sites of sandy seabed in the southern North Sea, UK (Bonne 2010) found that ceasing aggregate extraction did not lead to changes in invertebrate community composition, or increases in species richness, biomass or abundance, after five years, which all remained different to that of two natural sites where extraction did not occur. Invertebrate community composition did not change from one year to another at any of the sites. After five years, community composition at the extracted sites was only 32.5% similar to that of the natural sites. In addition, average invertebrate species richness, biomass and abundance did not change from one year to another at any of the sites, and was consistently lower at the extracted sites (richness: 12–20 species/sample in 2001, 12–15 in 2004; biomass: 0.03 g/sample in 2001, 0.12 in 2004; abundance: 20–42 individuals/samples in both 2001 and 2004) compared to the natural sites (richness: 55 in 2001, 45 in 2004; biomass: 0.58 in 2001, 0.32 in 2004; abundance: 141 in 2001, 563 in 2004). In 1999, aggregate extraction ceased in a licence area. Between 2001–2004, invertebrates were surveyed yearly at two extracted sites within the licence area and two natural sites 1–15 km outside. Ten samples/survey/extracted sites and five/survey/natural sites were collected using a sediment grab (0.1 m²). Invertebrates (>0.5 mm) were identified, counted and dry-weighed.

(Summarised by: Anaëlle Lemasson)