Guide to the identification of North Sea fish using Premaxillae and Vertebrae

This guide arose from four years of collaborative work on the diets of seals carried out by the Department of Zoology, University of Aberdeen, and by the Scottish Office Agriculture and Fisheries Department Marine Laboratory in Aberdeen. In addition to examining regional, seasonal, and species differences in diets of grey seals (Halichoerus grypus) and common seals (Phoca vitulina) using traditional approaches based on identification of otoliths in faeces and gut contents (Pierce et al., 1989,1990b, 199 Ib,c,d), attempts were made to develop novel techniques involving serological detection of prey proteins (Boyle etal., 1990; Pierce etal., 1990a,c, 1991b),

and methods available for diet analysis were reviewed (Pierce and Boyle, 1991; Pierce et al., 1993).