Date: 9/11/17 12:36 pm From: Tim Rodenkirk <timrodenkirk...> Subject: [obol] Rufous/Allen's confusion on South Coast
After about the end of June, adult Rufous and Allen's Hummers head south and become hard to find. That leaves the female and young around. They often stay around longer but begin to disperse also. Trying to ID these female and first year birds to species is very difficult without getting good looks at tail feathers, something I imagine most observers do not even attempt to do. Instead many observers base their ID on location of these hummers assuming that birds in Coos are most likely Rufous and that ones found south in Curry are most likely Allen's- at least that is what I see on eBird. Over in the Willamette Valley where Allen's do not occur as breeders it is probably very likely that those females and young birds are indeed Rufous and are IDed as such into late fall where they are seen. On the south coast Rufous could easily migrate south into Brookings and for all we know some Allen's could linger or be around later in the season in Coos County. So I think all hummer observations in Coos and Curry of females and immature Selasphorus hummers from July through spring should most accurately be called Rufous/Allen's. Even during spring migration, female Rufous and Allen's are intermixed from Brookings north to about Bandon on a regular basis. I had a nesting male Allen's at my house this year in Coos Bay so they can nest further north rarely.
Bottom line is I do not think there should be any non-male Rufous/Allen's identified to species in Coos or Curry the majority of the year (nesting season being March through June, the best time to assume that the female with the male at a nest is likely the same species). Perhaps changing the filter in eBird would be the best answer?
The Selasphorus tend to linger longest wherever you can find flowering fuschias this time of year and I always call them Rufous/Allen's as adult males are pretty much all long gone.