dinsdag 10 juli 2012

A Yellow Ending

Our last ringing session of the year was held at my site and it's clear the woods have become really empty now.. Last year saw us ringing on the 10th of July as well and last year's session stood in big contrast with the ringing today. The birds have gone quiet, only very few birds were singing. The Robins continue, with every now and then a Song Thrush but otherwise it's quiet. No singing Wood Larks, Tree Pipits, Redstart or Pied Flycatchers (and so on) anymore. I think the latter two have moved away from their breeding grounds already, I didn't observe a single bird of both species. I was surprised to hear both Woodcock and Nightjar still singing during this time of year. I was able to make a recording of the Nightjar, as it was singing from a reasonable distance.

Nightjar, Caprimulgus europaeus by Fmeijer

During this time of year it should be booming with juvenile birds. There were quite a few juvenile tits etc. around but none were found in the nets. And if those are missing out, the numbers of birds ringed can be considered quite poor. Sometimes it's just a matter of luck..

The ringing today was not particularly boring, as the species diversity was reasonable - for the amount of birds being caught. The highlight of the morning was the male Yellowhammer that finally found its way into the net, after so much avoiding of the nets:)

Blackbird 1 - 2 new juvenile, retrap adult female and juvenile
Blackcap 1 - adult female
Great-spotted Woodpecker 1 - juvenile male
Goldcrest 1 - adult male
Robin 5 - 1 all new juveniles, 1 retrap adult
Short-toed Treecreeper 1 - adult female
Yellowhammer 1 - splendid adult male
Willow Warbler 1 - juvenile

15 birds in total..

Yellowhammer (Emberiza citrinella), adult male
Goldcrest (Regulus regulus), adult male
Short-toed Treecreeper (Certhia brachydactyla), female; this could be a 2cy because of the pattern (and now it's moulting, the large contrast) of the (brown/worn) old outer primary coverts. You can see the old ones have a narrow buffy/white shaft on the outer web, whilst the new ones have a dark buffy tip (adult type pc?) on the point of the primary coverts. I know that this feature can be used for ageing Treecreepers (Certhia familiaris), but I'm not sure it can be of use with the brachydactyla. This year and last year I took a look at the juvenile Short-toed Treecreepers and I found out that some juveniles had a smaller buffy tip (adult type?) but on the outer pc's this tip was sometimes somewhat larger. Others had more extensive buffy/white colouring , like the bird above. Here are just two random pic's to illustrate
Juvenile Short-toed Treecreeper from last year; note the outer primary coverts
Juvenile Short-toed Treecreeper from this year; note the smal(ler) tips on the pc's, the outer ones as you can see, somewhat larger. This is maybe not the best example as the wing is closed.. 

I don't know what experience/knowlegde other ringers have on this subject but I'm interested to know!

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