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)

Monday 11 December 2017

Knot update

On the 22nd September 2017 519 Knot were colour ringed at Formby point (see previous posts).  In the first couple of weeks we received about 100 sightings from the local area with good numbers feeding in land at Caldy wildfowl collection.  I knew Black-tailed godwit fed on swollen grain readily however I had never heard of Knot doing this.

In the 74 days since ringing we have now received over 860 resightings of over 350 individuals from 15 observers.  So far four birds have been seen in Ireland (Dublin bay and Wexford) and five to Morecambe bay with the remainder remaining around Liverpool bay. 



To put some some of scale on these data in the last 10 years a total of 328 Knot have been re-encountered (mostly retrapped) within the same estuary as their ringing site. In just over 2 months the efforts of 4 main observers have nearly tripled that total.  Assuming the level of observer effort continues and ideally increases we will be able to achieve estimates of survival at a resolution never before achieved on a UK knot population before. 

Additionally with a moderately consistent observer effort periods of emigration from the population should be detectable by seeing an increase in relative frequency of observations of the remaining birds.  Immigration is much harder to detect unless there is an arrival of colour marked birds from elsewhere.  Using sightings of these birds going elsewhere and observed emigration we will build up a picture of how individuals that moult in Liverpool bay use other wintering grounds in Northern Europe. 

As always any sightings of colour marked Knot with an orange engraved flag should be sent to Jim Wilson who co-ordinates this colour mark scheme.  Many thanks to Rose Maciewicz, Peter Knight, Richard Smith, Steve Hinde and the 11 other observers of colour marked Knot so far. Every sighting is valuable to the project and the results are so dependant on individual observations.

Many thanks to Richard Smith for the photo.

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