ML63364211
Chaetura sp. Chaetura sp.
投稿者
日付
場所
- 年齢
- 指定なし
- 性別
- 指定なし
観察結果の詳細
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.
テクニカル・インフォメーション
- モデル
- Canon EOS 7D Mark II
- レンズ
- EF100-400mm f/4.5-5.6L IS II USM
- ISO
- 800
- 焦点距離
- 400 mm
- フラッシュ
- Flash did not fire, auto
- Fストップ
- f/7.1
- シャッタースピード
- 1/500 sec
- 大きさ
- 1710 pixels x 1140 pixels
- オリジナルのファイルサイズ
- 282.44 KB