The Results from BlingThe Sanderling (Calidris alba), also called the wave runner, is a long-distance migratory wader that occurs worldwide in coastal areas (particularly on sandy beaches) during the non-breeding season. The breeding range is restricted to the High Arctic tundra of eastern Canada, Greenland and central Siberia. Despite their presence on sandy beaches visited by people, such as Dollymount Strand in Dublin or Red Barn in Cork, strikingly little is known about Sanderlings compared to many other common wader species. The Sanderling uses what is called the African-Eurasian flyway, migrating from their breeding grounds down along the Eastern Atlantic coastline to their wintering grounds along the coast of western Europe, the Mediterranean, Africa and the Middle East regions. The knowledge gained from studies carried out by determined and dedicated biologists has lead to the beginning of our understanding of these flyways. One way of accomplishing this understanding is to place metal bands on the legs of the birds with a unique code, which requires the bird to be either retrapped for the code on the metal ring recorded or by means of using a telescope and lots of patience! The advent of light plastic bands (called Darvic rings) allow the biologists to trap the birds, apply a specific code of coloured bands and then rely on the "citizen scientist" to record the combination of colour bands and report the each unique combination to the relevant authority. An example of this is illustrated below on an adult 'Icelandic' Black-tailed Godwit on its breeding grounds in Iceland. This bird breeds on the same farmland every year but has been re-sighted over the years during the Winter and Spring in Ireland, Britain and France! I was fortunate to be able to record some colour-ringed waders recently while photographing a mixed flock of Sanderling and Dunlin on a high tide roost in Dublin Bay. The flock numbered about 300. I spent about 4 to 5 hours at the site (a couple of hours either side of the high tide) taking photographs of the birds, and looking primarily for juvenile Sanderling and adults moulting out of breeding plumage. It is imperative that the birds are not disturbed on their high tide roosts as they are tired, hungry, cold and in recovery from their long migration from the hight Arctic. For example, at one point, while I was patiently waiting for a Sanderling with a set of Darvic rings to lower its right leg to reveal the full combination needed on both legs for the researcher, a person on a bicycle went by with a fishing rod pointing to the sky and flushed the flock out into the bay. I lost the bird with the combination of rings but luckily refound it again when the flock circled around and came back in again to land and snooze along the rocks. If this disturbance is constant, then the birds become tired, can't rest and recuperate, and may succumb to exhaustion. Therefore, using a telescope, binoculars and a long lens for photographs is important in these situations. (a flock of Red Knot is shown below) While scanning the mixed flock, I picked up a total of 4 ringed Sanderling, three with Darvic rings and one with a metal ring but with no Darvic rings. I was able to secure the combination of all the Darvic rings and read the ring number on the other bird, but could not get a complete code. I sent off the code combinations to Jeroen Reneerkens based in the University of Groningen, who is coordinator of the colour-ringed Sanderling project in Europe. Jeroen emailed me the data from each of the colour-ringed birds within a week (he was on holidays, otherwise it would have been even quicker). The results of the ringed birds were quite remarkable.
The bird above was trapped and rung in Iwik village, Banc d' Arguin, Mauritania (west Africa) on 12th December 2012. This is the first resighting of this bird. Incredible!! Will it head back down to Western Africa again this winter?
The bird above (blue flag) was trapped and rung in Samoucoo harbour, Rio Tejo, Portugal on 8th November 2012 by Jose Alves and Pete Potts. In fact, Pete has been putting Darvic rings on the Black-tailed Godwits like the one shown above in Iceland for many years. I had the pleasure of working with him for a few days in Iceland in 2009 so it was really great to read the rings on a Sanderling that was tagged by Pete. This is the first resighting of the bird as well! I emailed the image onto Jose and Pete, who were delighted to receive the resighting news and a photograph of one of "their" birds. I wonder will the bird head back to Portugal for the winter?
Where this guy with the metal ring, and all the unringed birds, have been during their breeding and non-breeding cycles is anyones guess. The worrying thing about this flock was the small percentage of the birds were juvenile (less than 10%), which reflects the very poor breeding season the waders have had in the tundra this year. Huge thanks to Jeroen Reneerkens for the sightings information ([email protected]). More information about the project can be found at the International Wader Study Group (http://www.waderstudygroup.org/res/project/sand-colrings-en.php). Please send any resightings of colour-ringed Sanderling to Jeroen at the email address provided and be mindful of the fact that these birds are tired and just want to get a bit of sleep. Comments
Floss Gibson(non-registered)
Great read, loads of information and some crackin shots - altogether pretty damned dandy!
shay connolly(non-registered)
Now that was a great read
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