Spotted Flycatchers are one of the easiest species to age in the Autumn requiring only a cursory examination. First year birds have prominent pale tips to the greater coverts, tertials and upper tail coverts, all of which can be seen in the field and in the photo above. These pale tips and edges are absent in adult birds. By the following spring, after a complete moult in their winter quarters, adults and 1st years are indistinguishable.
The Early Worm 