LEBRET T (1976) Short announcements: Fourteen gulls employing three thousand feet for worm trampling. LIMOSA 49 (1): 111-111.

Some 14 gulls were observed eating earthworms obviously brought forward by the foot trampling of some 1500 Barnacle Geese on a former tidal pasture on the Haringvliet b.ank on March 31st 1975. The gulls were searching for the worms while flying over the flock of geese. The phenomenon probably is a recent one and may be due to water pollution leading to a decrease of aquatic food. The elimination of the tide in 1970 may have caused an increase of earthworms in the pasture concerned. European Herring Gull Larus argentatus Greater White-fronted Goose Anser albifrons Common Gull Larus canus canus Barnacle Goose Branta leucopsis

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