Greetings All

Below is a response from Kenn Kaufman to a query by Ian Paulson.

I must add that I've seen photos from several observers from Wanapum Dam,
including a couple not mentioned in the website listed by Charles Swift. All
or conclusively Common Loons. The partial dark collar low on the neck, the
bill shape, the muddy auriculars, the quite dark hind nape/crown all point to
Common. Some of these marks, by themselves, may not eliminate Arctic, but in
total, they do. I also feel that the head/bill shape are more consistent with
Common.

Perhaps all the observers obtaining photos saw a Common, and those not
obtaining photos saw an Arctic, but this seems unlikely.

Virtually all Red-throated Loons have white flanks and many Common Loons do.
Some Commons even have the rear white flank patch so much associated with
Arctic. Even a very occasional Pacific can show a very Arctic-like flank. So,
this mark might help in locating an Arctic among a flock of Pacifics, but
beyond this, it is of modest use only.

Cheers
Steven Mlodinow

Hi Ian -- I looked at the links indicated, and all of the loon photos and
drawings from Wanapum Dam clearly show Common Loons. The presence or
absence of white on the flanks is irrelevant unless the bird has already
been established as being in the Arctic/Pacific Loon complex. It's a
very common thing for Common Loons (as well as Yellow-billed and
Red-throated Loons) to show white on the flanks above the waterline, and
I'm not sure how this point came to be regarded as exclusive to Arctic
Loon.

Kenn Kaufman
Tucson, AZ