Kittiwake
Rissa tridactyla
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Kittiwake used to breed in Berlengas in late 1970s. As a result of a natural expansion of the species through other areas of the Iberian coast, a small colony established in O-da-Velha Islet (Berlengas), reaching 19 couples in 1979. This was the southernmost location where kittiwakes bred. The reduced breeding success of kittiwakes in Berlengas led to its disappearance since 1982. In Portugal, the kittiwake is regionally extinct (RE) as breeder. Currently, kittiwake occurs in Portugal waters mainly in autumn and winter. It is distributed from north to south but it appears to be most abundant in the northern half of the EEZ. However, its abundance seems to be highly dependent on weather conditions on the north territories and offshore. The birds using national waters during the winter seem to come from Norwegian and United Kingdom breeding colonies.