Several days ago I asked for help on a jaeger ID for a sighting I had on Oct 7 in Barrow, AK with a photo in this eBird checklist: https://ebird.org/checklist/S74547169. First I wanted to thank the half dozen or so people that provided very helpful feedback. Secondly for those who are interested I wanted to give the decision along with the supporting arguments. The majority of people thought this is a Long-tailed Jaeger. Normally all Long-tailed Jaegers have left their tundra breeding areas for wintering in more southerly seas by mid-September and don't return north till May. In fact I was only able to find a single previous Alaska record for October and it was in Ketchikan (which is not near their breeding grounds). That is the main reason I was questioning the identification. However the field marks all point to Long-tailed Jaeger:


1. Measured from photo, the central tail feather extension is 30% of total length of bird from tip of tail to tip of bill. If that total length is 20", that makes the tail feathers extending 6" - in range for Long-tailed, Parasitic should be 2-4" max.
2. A LT Jaeger typically show 2 pale primary feather shafts while a Parasitic
would show 4-6. This bird in the photo on the closer wing clearly shows 2 lightish feather shafts with a third partial.
3. This bird shows a gray back contrasting with the black tail. This is characteristic of LT jaeger in alternate plumage. A Parasitic would have a brown back with little contrast to the tail. Birds of the World says that LT Jaegers would typically still be in alternate plumage in October and this bird shows no sign of having begun molt.
4. Some less definitive items: this bird shows no signs of either a breast band or a light mark at base of bill both of which are typically present in Parasitic but not LT Jaegers

Jim Elder (in Seattle but I was in Barrow last week)
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