ML63364181
Chaetura sp. Chaetura sp.
Contributor
Date
Location
- Age
- Not specified
- Sex
- Not specified
Observation details
Id as Chapman's Swift in the field, but pictures show very short tail, and could then be just Short-tailed Swift. It was a large group of at least two species (Band-rumped and what I identified as Chapman), flying low at the end of the day chasing insects over an open field. I spent some time trying to photograph these birds, without much success... The mysterious swift had an uniform brown rump. I observed that clearly in the field against dark background, and you can see that on some pictures. I don't think it was an effect of the end of the day light. I would expect a much grayer rump for Short-tailed Swift. I usually identify Short-tailed Swift just by shape, especially the typical notch at the base of the wings. Watching these birds for about 15 min, I never saw the usual shape of Short-tailed Swift and so discarded that species. Maybe the way of flight (very fast flight, hunting at low elevation) made the shape change enough to mislead me... All these brown-rumped swifts were molting their primaries (any of the Band-rumped were). I have no idea when are supposed to molt the local Short-tailed and Chapman's.
Technical information
- Model
- Canon EOS 7D Mark II
- Lens
- EF100-400mm f/4.5-5.6L IS II USM
- ISO
- 800
- Focal length
- 400 mm
- Flash
- Flash did not fire, auto
- f-stop
- f/7.1
- Shutter speed
- 1/400 sec
- Dimensions
- 1575 pixels x 1050 pixels
- Original file size
- 259.8 KB