THE DIET OF MEDITERRANEAN GULL (LARUS-MELANOCEPHALUS) CHICKS AT FLEDGING

The diet of Mediterranean Gull chicks was investigated in a Macedonian wetland using three different sampling methods: stomachs from freshly dead chicks (1988), regurgitations (1987) and carcass stomachs (1986- 88). In fresh stomachs, gastropods were the most important animal prey by mass and insects by numbers. In terms of overall volume and biomas s, wheat grains were the most important food. In regurgitations and ca rcass stomachs insects were the most important prey. Comparison of the results from the different methods revealed considerable differences which are attributed to feeding behaviour of the gulls and prey dynami cs rather than the methodology used. The importance of prey types is d iscussed; composition of diet probably differs considerably between ge ographical areas