Notes on growth and behaviour of the American razor clam Ensis directus in the Wadden Sea and the predation on it by birds

Abstract

Ensis directus (Conrad), a bivalve found in Europe only in the past few years, has filled an empty niche and spread rapidly over the intertidal flats in the Wadden Sea. The growth of the animals was investigated using a few samples taken near Langeness in February 1984. The age of the animals could be determined by reading the clearly visible year marks on the shells. Notwithstanding the low density of E. directus, some oystercatchers appear to have already specialized in feeding on this new food source. © 1985 Biologische Anstalt Helgoland.