KIST MJ (1951) Third record of Larus melanocephalus in the Netherlands. LIMOSA 24 (1): 3-6.

On June 3rd 1950, amidst a little colony of reeding Blackheaded Gulls (Lams r. ridibundus L.) at the bird sanctuary "De Beer", Hook of Holland. a specimen of the very rare Mediterranean Blackhheaded Gull (Lams melanocephalus Temm.) in full summer plumage was observed. The melanocephalus was sighted several times in the course of June, always at the same place among the breeding Blackheaded Gulls and often attacking other gulls within Its neighbourhood. but it prayed to be impossible to ascertain whether it was paired to a common Blackheaded Gull as was the case in 1935 on the Isle of Schouwen.The bird was photographed and filmed and last seen on July 2. Mediterranean Gull Ichthyaetus melanocephalus = Larus melanocephalus

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