Another slow morning this morning with the number of birds ringed struggling to reach double figures (totals online — click Ringing); that did include five Icterine Warblers, though — always nice birds to handle and quite easy to age (their iris turns from green to brown, similar to Acrocephalus warblers). The weather is still good (clear, warm and not too windy) and we're wondering if this might be it; if all the birds have passed and that the spring season is now effectively over.
A 2cy Common Rosefinch was singing by one of the nets as I walked around the garden:
You can hear that the song at the start is a bit "flat" and with a few extra notes — this is, presumably, the as yet uncrystallised song of this young bird. The recording above is split in two parts — one from when I first started recording the bird and one from a minute or two later when I'd got a little bit closer. You can hear that, even in that short time, the bird has started to sort itself out a bit and the song sounds a little bit sharper in the latter part of the recording (NB the increase in volume is because I'm now half the distance from the bird!).
But still, when you compare the song to this bird from last week— an immature, a 3cy I think (see here) — you can hear that the 2cy bird still has a bit more to do with its song.
You can see the differences on a sonogram, too. Included here are the first song phrase from the recording of the 2cy, the last song phrase from the same bird, a song phrase from the imm. bird, and a song phrase from an adult male recorded by The Sound Approach. Even though — compared to the 2cy — the immature bird song sounds quite crystallised, you can see it still has a way to go before it becomes as clean and simple as the adult male's up-up-down-down song phrase.