Juvenile blackbirds should not replace the primary feathers (or primary coverts) as part of their post juvenile moult. However, adult birds should moult the wings entirely, resulting in no contrast in the flight feathers. First winter males have dark bills that gradually become yellow over the winter. Bill colouration here indicates a first winter bird. Pictures are below:
|Blackbird LA75666 showing different generations of feathers in the wing.|
The blackbird appeared to have replaced its tertials, all of its coverts and several primaries (see the middle of the three arrows on the photo above), but had also retained some secondaries and its inner-most primary (see left arrow), and its outer primaries (right arrow). It can be seen that retained feathers were bleached, more worn and pointed, compared with the darker, more rounded replaced feathers. The bird had also replaced all of its tail feathers.
Any comments on the blackbird – particularly experience of similar birds from other ringers – would be useful. Are we missing something here?
Thanks to Heather Coats, Cedwyn Davies, Emma Cole and Darren Hicks for company and assistance this morning.