Thursday, 20 August 2015

Sexing juvenile Siskins.

 Today there has been a flock of about 60 Siskins at my ringing site. I have not had much luck tape luring and the call did not seem to work. I decided to try the song. It was a little more effective and I caught seven birds.
 In the recent Ringing and Migration I had read an article on sexing using the amount of black on the second outer-most tail feather. I decided to give it a go.
 On some birds the blotch went almost to the base of the tail. It was difficult to measure, but the longest I recorded was 29.9. I presume a female, but it needs to be above 30 to be certain according to the paper.

 An adult male was  25.2 and a 3j had a measure of 24.5. The shortest I recorded was 17.8 on a 3. See below. Both these juveniles had some black feathers coming on the crown so I was able to sex them without the tail criteria.

 It was good to see so many Siskins and I am sure some have bred locally.

Tuesday, 11 August 2015

Nervous nineties

The team assembled at the treatment works 'scrub' this morning based on my optimistic but hopeful promise of a 100 bird session.

Just like a batsman entering the nervous nineties we got to the final net round about 11:30. One had about 10 birds but the others had precisely .... none. The umpires decision? 'out' LBW (Little Brown Warbler) but we made 92.

The remarkable thing about this site in July and August is that the vast majority of birds are post breeding migrants, It's hard to know quite where they all come from as a number of species ringed in the last 3 weeks certainly do not breed on site and today's total included a number of cases in point. This juv Yellowhammer was actually a site tick.

Other non residents included Garden Warbler and Lesser Whitethroat. The 'scrub' is however Whitethroat central and we have ringed large numbers of this years birds including a very creditable 25 today.

Friday, 7 August 2015

Juvenile Siskins at Hicks Lodge.

 Ringing at Hicks Lodge this am resulted in a new site ringing tick. Three juvenile Siskins were caught.
 Siskin is classified as a very rare breeder in the county, but these two look like they have not travelled far. A probable breeding record.

 A total of 20 birds were caught including Whitethroat, Garden Warbler, Blackcap and Willow Warbler.

Sunday, 2 August 2015

Juv Goldcrest gets its 'crest'

Two of the first three birds caught and ringed at the sewerage treatment works yesterday were juv Goldcrests. The first was in completely juvenile plumage - no crest, but the second was undergoing its post-juvenile moult, replacing fluffy olive green crown feathers with the characteristic 'gold' feathers that give the species its name. Interestingly not only is this individual growing yellow 'gold' but orange 'gold', so it can confidently be identified as a male, even at this early stage.