NLRG was formed in 1957 to help in the study of birds in the Lancaster and District Birdwatching Society area. There are currently 12 active ringers. Species currently being studied include: Pied Flycatcher, Bearded Tit, Sand Martin, Twite, Goosander, Oystercatcher and Grey Wagtail. Migration has been studied for 28 years at Heysham. We welcome anyone who wants to observe, help or perhaps wish to become a ringer. Photo: A Heysham-ringed Twite on the Mull of Kintyre (thanks to Eddie Maguire)

Wednesday, 20 August 2014

A tail of two Knot

On a recent trip to the Wash as part of the Wash Wader Ringing Group's summer fieldwork activity a catch of Knot was made in Lincolnshire.  While the number of Knot retraps is always low due to the large numbers around and relatively small numbers ringed each year we did have around 1% of the catch as previously ringed on the Wash.  We also retrapped a bird originally ringed on the 14th February 1998 at Heysham, Lancashire. 

This kind of movement is exactly what we would expect from a wintering Knot at Heysham.  In autumn flocks of many 10s of thousand or even 100,000 form on the Wash where many moult before dispersing to estuaries around the UK and Northern Europe.

While looking at the excellent BTO online recoveries page to see how many have been recorded making this movement before (90), I noticed a rather surprising movement to the Canary Islands.  On further investigation I found this blog which even has photographic evidence of this unusual movement.  Interestingly this bird to the Canary Islands was caught in the same catch at Heysham back in 1998.

The Canary Islands, although a long way away, is not a surprising location for Knot to winter.  What is surprising is that all knot in Morecambe Bay in winter are of the Islandica race which breed in Greenland and Canada then winter in Northern Europe with a few reaching as far south as Portugal. Normally I would have expected a Knot on the Canary Islands to be from the nominate Canutus race however mid August is awfully early for them to arrive on their wintering grounds, particularly as this was still in summer plumage.  How this bird reached the Canaries is a mystery however as they are long distance migrants that do cross large expanses of ocean it is possible a storm picked it up somewhere further north, alternatively it became horribly lost.

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