Dan asked: "There is a pretty solid ring of red feathers along the bottom of its gorget. The upper 2/3 of its gorget is white. I'm thinking this must be either a hummer that was born very late last season and does not yet have its full adult gorget (not even close), or it's an adult male that has some kind of feather defect. Any thoughts? Any other northerners ever see one like this during spring migration?"
NLN: Dan, my take is that your first 'guess' is correct. Nearly every winter, we see late developing youngsters here in the South. There were fewer this past winter than usual. It is getting a bit late, but I have seen these 'late bloomers' in early May. Whether this is evidence of a late hatching or of retarded development is open to supposition as I have no way to actually determine the hatch date. However, my guess is late hatching rather than retarded development.
Now, the white that you see on the upper gorget is likely to be new gorget feathers still enclosed in the sheath. The forecrown and upper gorget area are the last parts of the plumage to molt. These sheathed gorget feathers are dark when they first emerge so you would likely not notice the difference, but they dry to white and will remain like that for only a day or two. Then, the bird will scratch his gorget a lot and the sheaths will explode into a fine powder and you will see a fine-looking adult male - like magic!
Nancy L Newfield
Metairie, Louisiana USA
USDA Zone 9b