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)

Saturday 2 August 2014

Pied Flycatchers Have a Succesful Season

We run a RAS scheme on  Pied Flycatchers in 15 woods in the upper  Lune valley and its  tributaries. Yesterday we had  a group get together to  talk over our study. This year we have had 83 occupied nest boxes well up  on the 59 in 2013 and a return to the levels of previous years. We also monitor  another population in Bowland of 8 pairs this year.They have all bred very successfully and we ringed 536  nestlings in total and caught or retrapped 111 adults.

In recent years there has been a marked change in distribution with a decline in the lower altitude woods with three woods losing their birds completely but there has been a corresponding  increase  in the higher woods  with the medium altitude woods retaining their populations.
                           
                         
There is the possibility that the provision of more nest boxes in the upper woods that  they have drawn birds away from the lower woods, but there is no support for  this view from our ringing retraps. Another possibility   we considered was an increase in competition from other hole nesting species such as tits but all our woods have plenty  of unoccupied boxes. So the main conclusion was that the distribution changes related to ecological and possibly  climatic change in the woods and we hope to set up a sampling program to compare   occupied and un-occupied woods.

Our ringing over the years has shown that just 3.9% of the nestlings are recorded again. Of those that return to breed 34 % return to their natal wood-50% move to other woods within the Lune Valley and 16%  move  further afield  Most of these are found in  Northern England with smaller numbers from Wales and South West Scotland. Some though are more adventuress. Nestling ringed in our boxes have been found breeding in  Germany and Denmark. It all helps to spread the gene pool.

By contrast adults mainly return in successive years to their native wood with  just 15% moving woods within the Lune valley. A  few do move further afield. One female ringed while nesting in Galloway moved to our area to breed next year, then north again to  Cumbria the following year.
John
    

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