In both photos, the supercilium appears to reach the bill base, pointing away from Arctic.
在这两张照片中，眉斑看来皆往前延伸到嘴喙的基部，这点便和极北柳莺不同。
2
The majority of Arctics to my eye seem to have ochre-toned legs, and the supercilium does not reach the bill (which can be very hard to judge in the field).