ML71570651

Age

Not specified

Sex

Not specified

Observation details

The separation of immature/female Rufous and Allen's Hummingbirds has to be done with care, and requires detailed photographs and examination of the tail. Even with this, some individuals cannot be safely separated. It is necessary to definitively age and sex the bird before making an appraisal of factors that support one species or the other. Fortunately this individual (at least in my opinion) shows enough characters to support identification. The center two retrices (R1’s) lack any rufous color in the exposed areas and appear uniformly colored, which is supportive for sexing as a female. These rectrices are also noticeably broad. This, combined with the lack of any visible rufous is good for ageing as a HY. R2 is noticeably broad and has a thin whitish tip. It only has a faint emargination and a hint of a notch on the inner web (this might also just be wear of the white feather tip as these photos suggest; some have referred to this as "pinching" on the inner web which is more obvious in males, but they are probably not seeing the white area at the tip of R2). Overall the pattern of R2 is supportive for a HY female Rufous. R3, R4, R5 show white tips and the tips of these feathers are broad. They do not give a narrow impression, as one would expect with Allen's. Also the rufous in these rectrices meets green and not dark, which is supportive for sexing as a female. The overall broadness of the rectrices tips is good for Rufous. The uppertail covert pattern is similar to that of the rump and mantle, i.e. green with only thin rufous fringes. Allen’s usually shows obvious rufous color in the uppertail coverts, so this makes a stronger case for identification as Rufous.

Technical information

Model

Canon EOS 7D Mark II

Lens

EF400mm f/5.6L USM

ISO

800

Focal length

400 mm

Flash

Flash did not fire, auto

f-stop

f/6.3

Shutter speed

1/640 sec

Dimensions

1918 pixels x 1221 pixels

Original file size

342.47 KB