EGGENHUIZEN AHV, MAASSEN EJ (1987) Short contributions: Great Black-backed Gulls Larus marinus and Herring Gull Larus argentatus with hanging wings. LIMOSA 60 (2): 84-84.

Observations of birds with hanging wings in IJmuiden and Amsterdam (NH). At one occasion the Great Blackbacked Gull behaved submissive towards conspecifics, after which the latter ignored the former. Herring Gulls showed less prudent behaviour against the bird than normal. The aberrant posture was not considered as aggressive or impressive behaviour. Great Black-backed Gulls Larus marinus and Herring Gull Larus argentatus with hanging wings

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