Elinor - there's a remote possibility the smaller hummer you saw could be a Costa's Hummingbird. The adult female is smaller and dingier looking on the throat and breast than the Ruby-throat. It sometimes presents a slouched posture. Also, it has a shorter tail than a Ruby-throat whose tail extends beyond the tip of the primaries; Costa's tail does not extend beyond the tips of the primaries.
Bob YunickSchenectady, NY
From: Elinor Osborn <0000037bc09f69f4-dmarc-request...>
Sent: Tue, Jun 9, 2020 11:47 am
Subject: [VTBIRD] Ruby-throated
This spring, in May, two female ruby-throated hummingbirds showed up on the same day. One had the usual pure white throat and breast, the other had a dingy white breast and seems smaller. The back is duller than iridescent green and has some white blotches. Now, sometimes they are both on the feeder at the same time. The dingy one sits hunched while the pure white one stretches up tall. It’s not time for fledglings yet, so I’m wondering why the smaller one has this strange plumage?
Elinor Osborn Photography
1286 Lost Nation Rd
Craftsbury Common VT 05827