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)

Sunday, 16 December 2018

Not the normal Knot movement - 18th record of a BTO ringed Knot in Africa

Update - Corrected flag code but similar story.

One of the many things that has come out of the Knot work at Formby is the vast amount of data being produced by a small team of dedicated observers which have made nearly 4,000 observations.  These are all really valuable and without your help many an interesting pattern of movement or important bit of connectivity between sites would be missed.

An email last week was very interesting with the report of a Knot seen twice in Mauritania which had been ringed at Formby in 2017.  I expected this to be either the bird that was seen on the Azores (although unlikely as it looked in pretty poor condition in the last photo) or the bird that was identified as canutus when we caught it in September 2017.  It turned out to be neither of these and in many ways much more surprising.

Orange HA was indeed ringed in September 2017 at Formby as a moulting adult however was seen up until 29th October before disappearing.  It's next sighting was in Mauritania this December.

This is the 18th recorded movement of a British ringed Knot to Africa with previous records in:

Congo - 1
Gabon - 1
Ghana - 1
Liberia - 1
Mauritania - 4
Morocco - 1
Mozambique - 1
Republic of South Africa - 3
Senegal - 4

16 of the 17 have been ringed as juveniles in August and September, the 17th ringed as an adult in July 1973 before being found in South Africa in December 1973. Additionally all but one of these were ringed on the East coast of the UK.  These are all typical movements of Knot of the canutus race.

What makes HA particularly interesting is that it was in the UK so late into October when the previous latest record of a Knot in the UK going to Africa was 25th September.  Clearly having a colour mark here helped get a closer to departure date than a single capture however a month later than the previous latest is surprising.  Was this in the wrong place with a group of Knot not wanting to migrate or was it something else?

With metal ringing alone we might have had some details of it in Mauritania if conditions were good however we certainly would not have had any sightings in the UK post ringing.  Similarly with the bird on the Azores - we may well have had enough photographs to identify the bird but again the intervening records would not be present as a result of the difficulty of approaching Knot in the UK in autumn and winter without causing disturbance.  Once again this highlights the value of colour ringing difficult to monitor species such as Knot.  We are not only getting excellent survival data thanks to the efforts of the local observers but we are also getting fascinating movement data from the global network of keen colour ring readers and one which I would recommend everyone tries as you never know what interesting bird movements you will record.

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