The escallop, Pecten maximus (L.), in Killary Harbour

Abstract

Escallops (843) collected by SCUBA diving ranged from one year to an estimated seventeen years old and varied in shell height from 17mm to 164mm. They were predominantly found on the slopes on either side of the Harbour at depths between 6m and 35m; very few specimens were observed on the soft mud in the centre of the Harbour. The density of escallops increased towards the mouth of the Harbour. The greatest numbers of specimens of less than 50mm were observed at the mouth of Killary. Variability in age frequency distributions along either side of the harbour could be explained by differences in settlement intensity from year to year. Settlement appeared to be more successful on the southern side than on the northern side. It also appeared that local dispersion from settlement areas occurred rather than active migration. Escallops four years old or less swam regularly while swimming was less frequently seen in individuals exceeding five years of age. It was concluded that Killary Harbour was unsuitable for the collection of spat but may be a suitable area for escallop cultivation.