Monday, 10 January 2011

Fat Robins at Cardington, 9th January 2011

A short session at Cardington, with nets open from 10:30am until 1pm. There was still some frost and puddles were frozen (see right), the sun was burning the frost off and the streams were flowing. Not too many birds around, there were fewer Fieldfares in the area than the previous week, 1 or 2 Goldcrests in the bushes, 1 Great Spotted Woodpecker calling.

Totals for the session were as follows (retraps in brackets):
  • Blue Tit 1 (2)
  • Goldfinch 2
  • Great Tit 3
  • Long-tailed Tit (1)
  • Robin (2)
The retraps included 3 birds initially ringed in the autumn of 2009 (1 Robin and 2 Blue Tits).

Both retrap Robins were above the maximum expected by the IPMR software - which expects the maximum weight for a Robin to be 24.5g:
  • P546652 had fledged in 2009. It was ringed on 31/8/9 and weighed 19.6g. When retrapped on 9/1/11 it weighed 25.6g.

  • P546799 was ringed on 28/11/10, but was not weighed that day. When retrapped on 9/1/11 it weighed 26.9g.
The two species that appear to be putting on more weight than any others are Robin and Dunnock. Perhaps I should stop offering sunflower hearts, but provide a less-energy packed food instead.

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