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This week we recaptured a rather special Lesser Redpoll at Bourne Wood, having been ringed there in March 2014. Nothing too special about that, as we regularly retrap Redpolls in subsequent winters – however this one had been previously recaptured up in South Lanarkshire in October 2015, between our two capture dates. The subsequent reporting rate for ringed birds of Redpoll size is around 1%, so the chances of getting one found 400km away and then back again is probably about a 1 in 10,000 chance.
This week we caught probably our last handful Redpolls of the season, all females and developing brood patches indicating that they would be departing very soon for their breeding areas further north. I find it fascinating how distribution changes over the years, as when I started ringing in the early 1970's, Redpolls (one of my favourite birds) were a common Lincolnshire breeding bird (breeding in my garden) and migrated south to southern England and Belgium/France in winter. Strange that forty years later, Redpolls now rarely breed in the county and are normally found here only in winter.
Also strange is that Redpolls are quite site faithful to their wintering areas, whereas Siskins (that have a similar breeding distribution) are not. Of 1,000 Lesser Redpolls ringed at Bourne over the years, we have had six subsequently found in Scotland and several movements involving Norther Ireland as well as some that we have ringed on passage that have been found in France/Belgium.
Siskins on the other hand generate more interesting movements as they are not faithful to wintering areas(explaining why some years we get a lot and other years none at all) and can winter over a thousand kilometres from where they spent the winter previously. Of over 3,000 Siskins ringed at Bourne we have had 25 movements involving Scotland and a couple to Scandinavia and many more all over England, but have also had one found in Slovakia, and others that we have caught have been ringed in Switzerland and the Czech Republic. Unlike our Redpolls, to date we have never retrapped one of our Siskins in subsequent years.
Alan
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