Monday, 21 May 2012

Disappearing Ducks.

Long-tailed Duck. Dave Appleton.

The record of  a Long-tailed Duck (LTD) off Starr Gate at Blackpool - and one or two other records recently - has prompted me to write up a post about the decline of seven species of sea duck, the numbers of which have fallen by up to 65% over the past 15 years including some that winter off the UK coasts, in particular the LTD and....

 Velvet Scoter. Dave Appleton.

....the Velvet Scoter (VS). 

The mysterious nature and the challenges of monitoring sea ducks have meant that the situation had largely gone unnoticed. Key coastal areas like the Moray Firth in Scotland indicate that VS numbers have declined from an amazing several thousand to a worrying less than 100 in under a decade, and LTD's have plummeted tenfold to another worrying figure of less than 1,000. Similar declines have been reported from the Baltic Sea which appears to suggest that these birds aren't just going elsewhere....they are disappearing.

Eider. Dave Appleton.

More shocking declines have also occurred amongst common and widespread populations such as the Common Eider which has halved in under 20 years. The causes of these declines are unknown, though the widespread nature of them indicates that they are linked to environmental change across much of the arctic and sub-arctic regions where most of these species breed.

Sea ducks occur in remote areas in summer and winter periods, making numbers and habits very hard to assess, attempts to pinpoint the reasons behind these declines are difficult, though suggestions do of course include human activities, like over-fishing of mussels, by-catch in fishing nets, and oil spills are three prime examples.

WWT is to set out a strategy and is asking parties for support in developing international research in tracking migration routes and studies in breeding areas, in particular in Russia. 

Thanks to Dave Appleton for three excellent photographs of three excellent sea duck species.

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