Black-tailed godwit
The Dee Estuary is an internationally important wintering site for black-tailed godwits, whose historical decline in the UK has caused conservation concern.
Numbers are now increasing and the estuary hosts between 4000-5000 of these large wading birds.
In 2004 scientists at the University of East Anglia made a remarkable discovery about the breeding behaviour of the long-lived black-tailed godwits.
These monogamous 'love birds' establish life-long relationships which can last up to 25 years, despite, or perhaps aided by the fact that the winters are spent around 600 miles apart. The majority winter in Ireland, Britain, France and The Netherlands but some venture further south to Spain, Portugal or Morocco.
Despite the distance, the pairs manage to rendezvous in Iceland each April or May, arriving within three days of each other. The few pairs in the study who failed to synchronise their arrival didn't mate, and the females found themselves another partner instead.
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