These images are not as sharp as I'd like, but they do illustrate
certain characteristics that point to very delayed plumage
development of an adult bird. This adult female Ruby-throated was
banded in early February 2006 at which time she was in the early
stages of wing molt. All molt was complete when she was captured
again in late April 2006, but she did not show any signs of breeding
- visible ova, swollen cloaca, or fluid-filled body cavity. Local
females usually exhibit breeding condition in late March or early
April. However, given her molt condition in early February, it seems
unlikely that she would have completed molt in time to be in synch
with local breeders. It seems likely that she migrated northward to
nest later in the season, but we don't have any concrete proof of that.

This bird was not known to be present at the site during the
2006-2007 winter season. However, she might well have wintered
nearby. She was captured during weekly banding operations on 15
April 2007. A multi-year returnee female Rufous with a similar molt
pattern appeared under similar circumstances at the site on 8
April. Note the pin feathers still emerging on the crown and
throat. Also note that primary #10 is not completely
emerged. Primary #9 shows only about 10% molt. Clearly, this
individual is not yet ready for migration [if she migrates] or
nesting chores [if she is a local breeder].

Please post your comments to Humnet, humband, or
the Hummingbird Forum rather than to the web
site.
Nancy Newfield
nancy@casacolibri.net