I mentioned this bird in last week’s Rare Bird Alert as one of the highlights of a good week in western Alaska. The report may be a little stale, but I figure the photos that have surfaced are good enough to give this very rare bird it’s own spotlight.
On June 9, a group of birders at Gambell, on St. Lawrence Island, found an ABA Code 5 Common Chiffchaff. This would be the third ABA Area record of the species, all from Gambell and all in the past 24 months.
This exceptional photo shows the noteworthy characteristics distinguishing this species from Willow Warbler, also very rare but a number of Alaskan records. Note the short primary extension, blackish legs and feet, and the gingery wash to the lower auriculars.
Common Chiffchaff was first documented in the ABA Area in June 2012 in Gambell. Another was seen in September of the next year. A Phylloscopus on St Lawrence Sept-Oct 2011 was not accepted but was also a good candidate for chiffchaff.
Common Chiffchaff is a wide-ranging breeding bird in the Palearctic, with three known subspecies that some authorities consider good candidates for future splits. The nominate subspecies breeds in Europe east to Poland, while the subspecies tristis, known by many as Siberian Chiffchaff, breeds from Siberia east to eastern Russia. The two subspecies do not recognize each other’s songs, but field identification is very difficult and may be impossible. Chiffchaffs in the far eastern part of their range tend towards being duller than those in the west, and perhaps not surprisingly, the Alaskan records are thought to be these dull tristis birds.