Here are two birds from this morning demonstrating close to either end of the variation:
This 2cy female Greenfinch is at the lower end of the scale having undergone a rather limited post-juvenule moult; it's retained seven juvenile greater coverts along with all the other 'large' wing feathers.
In contrast, this 2cy Goldfinch has undergone a rather extensive post-juvenile moult having eccentrically moulted two primaries (p5 & 6) — but not the corresponding primary coverts.


No comments:
Post a Comment