Over bengaalse sterns Sterna bengalensis en audouins meeuwen Larus audouinii in Tarifa (Spanje)

Three records of Lesser Crested Terns, concerning a total of at least 8 individuals (6 adults and 2 1st cy) on the beach of Tarifa (southern Spain) on 3, 8 and 11 October 1988 are discussed. Direct comparison with Sandwich Terns showed that adults were evidently darker on their mantles, while on the contrary the juvenile birds were lighter. Comparative field characters with both Sandwich Tern and the American Elegant Tern are briefly commented upon. The adults were easily picked out of the Sandwich Terns with which they sat on the beach because of their darker backs and the darker heads (at this time of the year). The origins of these birds remains rather obscure, since in recent years neither in Lybia nor in Tunesia any colonies have been found anymore. On the other hand recent colonizations of a few pairs (sometimes mixed with Sandwich Terns) have been recorded in France, Spain and Italy. In West-Africa some hundreds have been seen wintering, but most autumn passage takes place along the Moroccan coast. In Spain most non breeding records come from the very beach of Tarifa and winter visits in future should reveal whether possibly some birds might winter here, as they seem to do in Morocco. Audouin’s Gulls have increased considerably in the Mediterranean in recent years and so have numbers seen at the Tarifa beach. The maximum daily count in October 1988 amounted to 9 individuals, but peak numbers occur in August and daily counts have exceeded a 50 birds. It was noted as remarkable that the 1988 birds seemed to be more shy than other species of gulls, whereas visits in 1979, 1980 en 1984 had shown the reverse. Increased human visits of the more important colonies (mainly by investigating ornithologists) might have something to do with this.