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 8 September 2013

10,000th Swallow at maize field roost

Since 2004 North Lancs Ringing Group have ringed swallows every autumn in a maize field near Hornby.  Initially we started ringing there as part of the swallow roost project and more recently to continue marking some birds passing through the North West of England.  The numbers of birds ringed each years varies massively due to productivity and autumnal weather conditions.  This year we have caught just over 800 with a few weeks of swallow ringing left before the maize is harvested.  When entering the last visits data I noticed we had passed the milestone of 10,000 swallows ringed. 

Below are the totals for all years since 2004:

Year Total new New Juvs New Adult % adult Controls Recovered
2004 1585 1556 29 2% 6 8
2005 1811 1742 69 4% 7 5
2006 1409 1335 74 5% 2 3
2007 1247 1180 67 5% 1 3
2008 533 507 26 5% 1 1
2009 371 337 34 9%
2010 1213 1186 27 2% 1 2
2011 440 362 78 18%
2012 612 551 61 10% 1
2013 873 860 13 1% 1

10094 9616 478 5% 20 25

Ringing swallows at a roost is always going to produce low numbers of retraps as 95% of the birds ringed are juveniles.  Likewise as Hornby is a fair way north we are less likely to catch birds that have been ringed previously compared to sites further south on the Swallow migration route.

The map below shows the origin of all the birds previously ringed that have been caught at Hornby.  Markers with a green P have been ringed in the nest, red J have been ringed as juveniles with the same year and finally purple As are birds that have been ringed as juveniles but we have caught in a subsequent year as an adult.

The second and third maps show where birds that have been ringed at Hornby have been recovered or recaught. The green J markers are the sites where birds have been caught in the same year and the red As are where birds have been recaught in subsequent years.  One map shows the longer distance recoveries and the other is more local.

These maps tell a story which is a not too surprising one.  Most of the birds we catch are locally bred typically from the Lakes, North East England and Southern Scotland.  These are birds that are yet to find a coastline and are probably following rivers on their autumnal amble to the South coast. If we looked at the recoveries from a coastal roost such as Heysham or Fleetwood I wonder if we would find a different pattern of recoveries.

While Swallows are the target at Hornby we have also had some other interesting captures such as the group's only adult Merlin, 3 Yellow Wagtails, 175 Pied Wagtails and 20 House Martins.

Many thanks to the farmer and everyone who has lent a hand over the last 10 years at Hornby.

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