It comes as no surprise to find that eider ducks have declined dramatically since we have been visiting Shetland. Back in 1980's when we started visiting Shetland numbers we around the 10.000 mark but declined to 6,000 by 1997. A survey in 2012 funded by the Sullom Voe Association Ltd have found that 1,00 birds have been lost over the past three years.
Eider ducks are vulnerable to inshore oil pollution, and the Shetland Oil Terminal Environmental Advisory Group (SOTEAG) has monitored their numbers since the oil terminal was built.The Braer oils spill in the south Mainland in 1993 and the discharges by various fishing vessels over a period of time has contributed to the decline. Add to this predication of young by Gulls, Skuas and possibly otters as well adults have been killed by Killer Whales, this has only been seen a few times (Simon King video a few years ago) but more recently observed in the Faroes where 50 birds were killed in a matter of minutes. When birds become flightless in summer they become an easy target.
It seems that eiders in Shetland have changed their habits moving closer to aquaculture sites in the inner voes. Changes in weather conditions also have an effect on where birds will shelter.
Eiders feeding on mussel lines has caused some conflict and various measures are being tried out to deter the birds.
Shetland eiders are resident and studies suggest that they are closer to the Faroese race than those in northern Scotland.
N American borealis - breeds along the SW edge of Greenland (to c.75deg. N), extensively from southern Ellesmere Is., through Baffin Island, along the NE coast of Canada to meet dresseri at c. 54 deg. N; it winters off SW Greenland and around S Newfoundland;
dresseri - breeds and winters further south, from southern Newfoundland (54deg. N) south to Boston (c. 42deg. N);
sedentaria breeds and winters around the rim of Hudson Bay.
Eiders breed around the coast in Shetland although a number find moorland sites such as on Mousa, Unst and the North mainland attractive. They nest in colonies and sometimes they wont move off the nest. Eider down is still collected in some parts of Scandinavia but eider downs used for sleeping are a rare thing here in the UK.
There has been several sighting in Shetland of the northern eider but there is still alot of debate as to the identification, with several seen of Moray in NE Scotland showing sails and apparently one that was ringed in Moray as a young bird also showed these signs
N American borealis - breeds along the SW edge of Greenland (to c.75deg. N), extensively from southern Ellesmere Is., through Baffin Island, along the NE coast of Canada to meet dresseri at c. 54 deg. N; it winters off SW Greenland and around S Newfoundland;
dresseri - breeds and winters further south, from southern Newfoundland (54deg. N) south to Boston (c. 42deg. N);
sedentaria breeds and winters around the rim of Hudson Bay.
Eiders breed around the coast in Shetland although a number find moorland sites such as on Mousa, Unst and the North mainland attractive. They nest in colonies and sometimes they wont move off the nest. Eider down is still collected in some parts of Scandinavia but eider downs used for sleeping are a rare thing here in the UK.
There has been several sighting in Shetland of the northern eider but there is still alot of debate as to the identification, with several seen of Moray in NE Scotland showing sails and apparently one that was ringed in Moray as a young bird also showed these signs
King Eiders are always worth seeing and we have had a few sightings in Shetland, with the Tresta King Eider giving good views back in the 1990's, but too distant for any photos. Other have been around Unst or the north mainland and more recently a week or so ago 3 King eiders were found in the Bluemull Triangle (Unst)
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