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Saturday, 17 December 2011

Manor Farm Country Park Again...

With the predicted windy conditions not materialising, it was back to Manor Farm Country Park this morning for some more ringing. It was freezing and the heavy frost took its toll on my hands and feet, the latter still haven't warmed up this evening!!

We had a steady morning session which ended with 31 birds captured of which 13 were recaptures, most were fairly recent retraps, but two, a Dunnock and a Goldcrest were older.The Dunnock was ringed 2 years 298 days previously, but the notable one was the Goldcrest, which was ringed as an juvenile bird 3 years and 45 days previously. I have never previously retrapped a Goldcrest older than a year, so the age of this bird was quite a surprise. However, looking at data on the BTO website, it appears that the maximum recorded age for a Goldcrest is 4 years 10 months and 9 days, so our little chap has a little way to go yet!

Adult Male Goldcrest
Other species captured included five Blackbirds, three House Sparrows, a few Great Tits, Robins and Wrens. Another Linnet took our total for the year to 20 and this immaculately plumaged Blue Tit added to the cast.

Adult Blue Tit

There were hundreds of thrush's present, most of which were Fieldfare and Redwing, but the occasional Song Thrush was also recorded. We only captured one Song Thrush and two Redwing, despite our best efforts.


Immature Redwing

I was reading an article in the latest copy of BTO News about Redwing, which stated that the wintering population in most of Western Europe, including Britain, is the nominate race Turdus iliacus iliacus, with the race T.i.coburni, which breeds in Iceland and the Faroe Islands, wintering mainly in Ireland and northwest Iberia. However, there have been two ringing recoveries of this race in England, but it clearly is rare. So I started thinking how would I identify coburni if I caught one; the biometrics of the two races are virtually identical, although coburni does average slightly larger and the plumage overall is slightly darker, with heavier streaking on the throat and breast, and more extensive olive colouration across the flanks and under-tail coverts. 

Boldly Streaked Redwing

Looking at the two birds we captured today they both seemed to be boldly streaked on the  flanks and the under-tail coverts, but they lacked the bold streaking on the throat. Size wise they were both above average, with wing lengths of over 120mm, but given the variability in the species I think I am going to have to go to Iceland again and get my eye in before I am bold enough to claim one.

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