WALTERS J (1982) Short contributions: Early laying in the Black-headed Gull Larus ridibundus. LIMOSA 55 (2): 56-56.

Black-headed Gull Chroicocephalus ridibundus = Larus ridibundus On 31 March 1981 two Black-headed Gull nests with one egg each were found in a colony near Amsterdam (NH). On 15 April 1200 (out of 2000) nests contained eggs and on 10 May 3400 nests contained eggs and 270 had young (out of 3900 nests). This timing of laying is much earlier than previously reported for the Netherlands. It might indicate a trend for earlier breeding, which has been recorded also in several waders (e.g. Black-tailed Godwit Limosa limosa and Lapwing Vanellus vanellus; Mulder 1972, Beintema 1979).

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