I actually discovered it on my 8/20 survey, but this poor little bird on the 20th was already seething with maggots so I’m comfortable calling it an 8/19 casualty. This was a second year male. Check out the feather wear on his primaries. He was headed south to molt and then continue on further south.
With special guest stars James O’Connell and David Mallen, today’s survey turned up a male Indigo Bunting and a trapped Yellow Warbler at the main north entrance. (No photo of the warbler; it was a male.)
Let’s take a closer look at that Indigo Bunting:
He’s pretty blue, but his molt limits reveal him to be a second year (SY) male.
Those three big feather visible on the folded wing are the tertials (aka, secondaries 7, 8, and 9 from outer to inner.
Tertials from above. On the right wing, 7 and 9 are brownish and worn but 8 is fresh and blue/black. Tert #8 has been replaced but 7 and 9 are originals from when this bird was a baby last summer. On the left wing, 8 and 9 have been replaced but #7 is original.
Paper plate and packing tape makes it a bit easier to see some things.
Left wing: alulua, greater coverts, secondaries 5 and 6, and terts 8 and 9 have been replaced. Primary coverts, primaries, and secondaries 1,2,3,4, and 7 are orignal.
Close-up of head showing trauma to lower mandible from collision.
The multiple obvious molt limits on this bird illustrate two generations of feathers on the same individual, some of which grew in last summer and some which have come in quite recently. This confirms the age of the bird as second year (SY).