Intersex and sterility in the periwinkle Littorina littorea (Mollusca: Gastropoda) along the Western Scheldt estuary, The Netherlands

In this study we present the results of an intersex survey of Littorina littorea along the heavily polluted Western Scheldt estuary (the Netherlands), and record for the first time the intersex phenomenon in L. littorea from Dutch waters. Intersex differed significantly between localities and was the highest in the vicinity of the harbours of Antwerp and Vlissingen, as reflected by the I