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Published byAlfred Malone Modified over 9 years ago
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Hooge Platen Nature Reserve Bird island in a shipping channel November 13th-17th, Minsmere, Suffolk Rene Beijersbergen
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Westerscheld estuary
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Keeping an eye on the island
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Volunteers at work
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Little Tern breeding in the “safe haven”…
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Behind the “seawall”……..
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The beach, the seawall and the dunes
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Vegetation of annuals
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Waterdunen on the estuary
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Terns breeding on artificial sites
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Prey items fed to the chicks (left) and partners on the breeding site in three species of terns in the same period.
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Terns feed mainly on two species of fish Bottomdweller Poor swimmer Local Year round Live in shallow water (-20 m) Young and adult share partly same feeding ares H e r r i n g From surface to bottom Fast swimmer Migrator Young and subadults near coast from may-august Spawning area and nursery geographical separated Adults live from the Channel till the Norwegian coast S a n d e e l
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Years of poor reproduction by lack of food: Bodyweight of chicks does not increase over days Chicks die of starvation Both parents go out fishing Increase of predation
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So what can we conclude….. Feeding sites are getting more and more unpredictable when the function as a nursery for sandeel and herring is becoming less Breeding sites (Waterdunen & Zwin) are better off on close distance of nurseries and other spots where small fish aggregrates Terns are dependant on small fish for the young chicks and bigger fish for themselves The days when producing a clutch and the first days after hatching seems to be the most vulnerable days.
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