Tuesday 9 December 2014

Sorry about Knot blogging recently…

This week we received word of two Knot ring recoveries from the BTO. These birds were found dead at two separate locations on islands in the Wadden Sea on the northwest coast of Germany.

Wadden Sea Wikipedia

The Wadden Sea spans from The Netherlands along the coast of Germany and to the western half of the Danish coast. It’s an area well known to ornithologists as many species of waders, geese and ducks winter there, or use it as a re-fuelling or moulting area on their migration. 

The birds were cannon-netted and ringed on 30th January, 2014 at the Merrion Gate Spit on Sandymount Strand in Dublin Bay. 

Ringing (blue) and recovery (yellow) locations for the two Knots

The first bird (ST40506) was found on 24th July on the island of Helgoland, a total of 932 km from Dublin Bay. Helgoland is well known for its bird observatory and gives its name to a style of bird trap used to catch birds for ringing. The island is in the middle of a major migratory thoroughfare, so is superbly well placed for studying bird movements. 

The second bird (ST40507) was recovered on 12th August, 962 km from Dublin, at Sylt Island just off the German coast. This sandy island, connected to the mainland by a causeway, supports thousands of waterbirds each winter. 

Sylt Island, Wadden Sea, Germany Wikipedia

As both birds were described as “long dead” by the finders, it is most likely that these individuals perished on their way to their breeding grounds. They were most likely fuelling up in the Wadden Sea before making a two-step journey to their breeding grounds in Greenland and High Arctic Canada. 

Knot in breeding plumage during spring staging
in northwest Iceland
Jan van de Kam

From previous ring recoveries and re-sightings of colour-ringed birds, we know that the Knots in Dublin take alternate routes to their breeding grounds; some stopover in Norway and others stopover in Iceland. We’re delighted to get information on ring recoveries like these as they allow us to shed more light this intriguing situation.

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