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Hooge Platen Nature Reserve Bird island in a shipping channel. November 13th-17th, Minsmere, Suffolk Rene Beijersbergen. Westerscheld estuary. Keeping an eye on the island. Volunteers at work. Little T ern breeding in the “safe haven”…. Behind the “ seawall ”…….
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Hooge Platen Nature Reserve Bird island in a shippingchannel November 13th-17th, Minsmere, Suffolk Rene Beijersbergen
Prey items fed to the chicks (left) and partners on the breeding site in three species of terns in the same period.
Terns feed mainly on two species of fish S a n d e e l H e r r i n g Fromsurfacetobottom Fastswimmer Migrator Young andsubadultsnearcoastfrommay-august Spawning area andnurserygeographicalseparated Adults live from the Channel till the Norwegiancoast • Bottomdweller • Poorswimmer • Local • Yearround • Live in shallow water (-20 m) • Young and adult share partlysamefeedingares
Years of poorreproductionbylack of food: • Bodyweight of chicks does notincrease over days • Chicks die of starvation • Both parents go out fishing • Increase of predation
Sowhatcan we conclude….. • Feeding sites are getting more and more unpredictablewhen the function as a nurseryforsandeelandherring is becomingless • Breeding sites (Waterdunen & Zwin) are better off on close distance of nurseriesandother spots where small fishaggregrates • Terns are dependant on small fishfor the young chicks andbiggerfishforthemselves • The dayswhenproducing a clutchand the first daysafterhatchingseemstobe the most vulnerabledays.