ML21813651
作者
日期
地点
- 年龄
- 未说明
- 性别
- 未说明
观察细节
Found by B. Holden and D. Bell near the Sparrow Field (just south) on the east beach around 0640. Struck us as very odd, (colourless, pale, odd GISS) - many photos taken. Unsure of ID at the time. Recent research has strongly pointed to CACH (as suspected at the time). Observed again briefly on 15 May at the very tip. OBRC report in progress. Link will be added here when complete. Some notes: Wing Length/Tail Ratio - completed by D. Bell with photoshop pixel count. 15 images all indicate CACH. Proves to be a reliable method as known CACH and BCCH photos also measure out as such. Greater Coverts - Crossley ID Guide states that BCCH has black centres. CACH gray. Bird shows gray. Greater Coverts - lacking the white edging shown by BCCH. Proven to be strong indicator for CACH. Bib - highly variable in research (and within the same bird in different postures) - but matches better for known CACH than BCCH Bill size - bill appears smaller than the norm for BCCH, normal for CACH. Head - appears small headed (and rounder) than BCCH - especially when compared to photos of BCCH from elsewhere. Much like CACH. Nape - proven very unreliable field mark. No obvious differences between CACH and BCCH when using photographs. Tertial/Secondary edging - variable. Matches CACH better than BCCH on our bird. White on tail - Pyle states this is a BCCH feature, however we have found a large percentage of CACH show this feature - especially in the two northerly subspecies. (Very rare in birds from the southern USA). GISS - when observed in real life, the bird "stuck out like a sore thumb". Observation on May 15 was with 2 BCCH and it was independently picked out by us, and Alan Wormington who was ~30-40 feet away - as soon as it arrived. P.c. extima as subspecies by white edges to flight feathers (bold).
技术信息
- 型号
- NIKON D2Xs
- ISO
- 400
- 焦距
- 300 mm
- 闪光
- Flash did not fire
- 光圈
- f/8.0
- 快门速度
- 1/250 sec
- 尺寸
- 1212 pixels x 807 pixels
- 原始文件大小
- 893.57 KB