23 Oct 2015

More garden ringing.

The influx of Goldcrests and Coal Tits into the garden continues and follows a national trend. Three more Coal Tits were ringed recently wit ha fourth being a retrap form last month. Another Goldcrest was also ringed. Birds of interest included this adult Great Tit with a deformed bill ringed back in November 2011 as an adult making it at least 5 years old. Its bill was normal in 2011  and it looks as if the lower mandible has been broken at some point and the trauma has resulted in the whole bill growing deformed.

I also cuaght this interesting juvenile Goldfinch that had undergone an extensive post juvenile moult. Goldfinches can occasionally moult some of their primaries in their post juvenile moult but this was unusual in that it had moulted all the inner ones leaving p6 -p10 un-moulted. It had moulted most of its primary coverts leaving the outer two un-moulted and was in the process of moulting its tail. The wear on the tail and primaries was consistent with it being a juvenile bird rather than a bird born last year that had undergone an arrested moult.

Below: close up crop showing retained juvenile primaries and un-moulted primary coverts. The juvenile primary coverts are more pointed and have worn tips compared to the rounder nelwy moulted adult ones.

All interesting stuff and a final photo showing a Great Tit that had retained its two outer juvenile greater coverts during its post juvenile moult. Although Blue Tits commonly do this its much rarer in Great Tits.

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