This was my first experience of bird ringing. It was cold and frosty when I arrived at Wicken Fen Nature Reserve (National Trust) at about 7.45 a.m. It was just beginning to get light. Over the main reed beds a Marsh Harrier was being mobbed by a Crow. A second Marsh Harrier then came up out of the reeds.
Mist nets had been set in several locations around the education area near the visitors centre. It was not long before the first catches were brought back in small cloth bags. The first birds out were Robins, followed by a lovely Goldcrest.
Robin
Goldcrest
It was remarkable to note that a Robin (itself a fairly small bird) at 23.1g was nearly 5 times the weight of the Goldcrest (Europe's smallest bird) at 4.8g. A small bird can lose 10% of its body weight overnight.
Various factors are used to determine age and sex of the birds such as wing length, eye colour, inside beak colour and evidence of full adult moult.
Great Tit (Examination of the primaries to check for full adult moult)
Having dealt with the first batch of birds I joined the ringers in visiting the nets to collect the next batch. As the weather was so cold the birds could not be left in the nets too long (likewise in summer when the weather is hot). The trained ringers had little trouble removing the birds carefully from the mist nets and placing them in cotton bags for transportation to the ringing hut.
Mist net
Blue Tit in the net
Qualified/licensed ringers collecting birds
The full list of birds caught was:
Robin
Dunnock
Wren
Goldcrest
Blue Tit
Great Tit
Long-Tailed Tit
Blackbird
Redwing
Chaffinch
Goldfinch
Greenfinch
Bullfinch
Reed Bunting
Wren
Reed Bunting
This winter plumage Reed Bunting has a brownish head. In its summer breeding plumage the head is black. This is achieved by wearing off the outer edges of its head feathers to reveal the black colour underneath.
Redwings
Long-Tailed Tits
A family party of nine Long-Tailed Tits were caught together.
Greenfinch
After all details have been recorded the birds are carefully released unharmed.
The release
Data received from birds subsequently found from all the world provides valuable information for the British Trust for Ornithology (BTO) - see http://www.bto.org.uk/.
Data received from birds subsequently found from all the world provides valuable information for the British Trust for Ornithology (BTO) - see http://www.bto.org.uk/.
Other birds seen but not caught included Fieldfares, a ringtail Hen Harrier and several Snipe, including one which managed to escape an a diving attack from the Harrier.
Dunnock
Bullfinch (female)
Blue Tit
Blackbird
Dunnock
Goldfinch
Bullfinch (female)
Blue Tit
Blackbird
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