CAMPHUYSEN CJ (1993) Dutch Ornithological Union: Theme Day Gulls and terns: The importance of fish waste for nesting Herring gulls and lesser black gulls in the Dutch Wadden Sea islands: observations at sea. LIMOSA 66 (4): 168-168.

Dutch Ornithological Union: Theme Day Gulls and terns: The importance of fish waste for nesting Herring gulls and lesser black gulls in the Dutch Wadden Sea islands: observations at sea

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