- Certifier :
- Lloyds Register (Acoura)
- Certified status :
- Certified since :
- 20 Nov 2012
- Certificate expires :
- 30 Jul 2023
Ensis directus – razor shell or razor clam – is native to the western Atlantic. It was introduced to the German North Sea coast in 1978-79, and since then has rapidly spread through the North Sea and northern Europe. It reached the Netherlands in 1982, finding a free niche in the clean sand of the lower intertidal flats in the Wadden Sea.
After a free-swimming larval stage, razor shells burrow into the sand and filter-feed on algae. Birds such as eider duck and scooters are the main predators, while the larvae (spats) are eaten by crabs and fish. Razor shells can live up to five years and grow up to 16-17cm.
The gear type used in this fishery is a hydraulic dredge. This pumps water into the seabed, making the sediment become fluid and allowing the dredge to scoop up razor shells to a depth of 22cm. The shells collect in a steel basket to the rear of the dredge, with a minimum grille spacing of 11mm. From there individual shellfish are transported, via a pipe with a lift pump, onto the deck of the vessel.
The fishery is making a number of improvements as a condition of its certification, including defining harvest control rules within its management plan and monitoring, managing and reducing (where necessary) levels of bycatch.