Wednesday, 1 June 2011

1st June 2011 - Siskins and Firsts for Garden

31 birds ringed this week which started with a nest of four Robins at home which I had only just noticed on Friday (27th), which I quickly ringed before having to rush off to my brother's wedding!  Dressed in my tails it was probably the most presentable nest ringing ever done!  (Below - my brother's wife Abi with myself, best man Glen, Ben and Rob.)
This was followed on the Bank Holiday Monday with a netting session in the garden which resulted in just seven new birds, although did include a juvenile Dunnock, two juvenile Robins and my first ever warblers for May here - a Chiffchaff and a female Whitethroat!  The other two birds were also the first ever juvenile House Sparrows caught here in nearly three years (below)!
Then back to Leith Hill on Tuesday (31st) catching 20 new birds which included 16 juvenile Siskin.  As Siskin juveniles cannot be sexed on standard plumage I tried out the sexing criteria studied in Spain which looks at the size of the dark spot on the second outer tail feather.  This proved to have a huge variation in size from covering the whole feather (below top) to just the tip (below bottom).  With preliminary results showing that six were female and ten were male, but whether the British Siskins follow the same rule as the the Spanish is yet to be found out! Hopefully I will be able to catch these same birds again once they have undergone post juvenile moult and can be sexed on standard plumage as well to confirm these measurements.
Also caught was a juvenile Chaffinch which had an all adult tail (below), which had me fooled for a minute, and had presumably lost its tail at a very early stage and shows the importance of checking all ageing criteria.
Birds ringed:
Robin - 2 + 4 nestlings
Dunnock - 3
Whitethroat - 1
Siskin - 16
Blue Tit - 1
Chaffinch - 1
Chiffchaff - 1
House Sparrow - 2

No comments:

Post a Comment