ophrys's picture

Bullfinches

Observed: 3rd July 2011 By: ophrys
Yorkshire Naturalists' Union
ophrys’s reputation in Birdsophrys’s reputation in Birdsophrys’s reputation in Birdsophrys’s reputation in Birdsophrys’s reputation in Birds
bull m
bull m 1
Description:

An apparent pair caught and ringed together. The male was born last year, the female is older.

Identifications
Species interactions

No interactions present.

Species with which Bullfinch (Pyrrhula pyrrhula) interacts

Comments

WilliamB's picture

Bullfinch

How can you tell that the male was born last year, is it the bar on the wing?

William

WB

ophrys's picture

Greater coverts

Hi William

Yes...you are right. The wing bar is formed by the tips of the greater coverts. The inner 5 were replaced in its post-juvenile moult (last September), and so have broad white tips like an adult. The outer 5 are still juvenile, though, and have very narrow tips. They will not be replaced until it moults in September, this year. So, it can be aged as 'born last year' right through until early September. Once it moults in September, though, it will have adult type feathers throughout, and we shall only know its exact age through the ring number.

If you look at the female, her greater covert bar is formed by broad tips throughout, so hers is an adult wing type.

It is a bit more difficult than that, as some juveniles moult all those greater coverts in their post juvenile moult...in which case the carpal covert is considered (but that feather is not visible in either of these pictures).

Sorry to get all technical!!

;)

Ian
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