Vermont Rare Bird Reports 2019

Overcast, wind north-northwest 15-20 mph, air temp 39 F, water temp 54 F; bird's height above water (~50 feet) and eventual relative close proximity made atmospheric distortion insignificant.

Zeiss 8x42 TFL binoculars, and Nikon 60mm Fieldscope with 20-45x eyepiece set at 20x and Celestron 8-inch Schmidt-Cassegrain telescope with Celestron 18mm X-Cel LX eyepiece (effective 113x magnification) mounted on custom platform, Manfrotto 3066 video head and Manfrotto 132XB heavy duty tripod.

Have seen a number in California and Vermont, including a fair number southbound over Lake Champlain at this venue; also studied photos of Pacific Loons in flight the previous night (at length) in preparation for this lakewatch.

Narrow segment of Lake Champlain adjacent to mountain on New York side of lake and approximately 40 foot bluff on Vermont side.

Bird flew south roughly 50 feet above the water trailing about 20 feet behind a Common Loon. It flapped its wings continuously.

None heard

Bird was fortunately first seen approaching well in the distance, very near and slightly behind a Common Loon. The bird was flapping much faster than the Common Loon and was clearly smaller, though still obviously a loon. This immediately narrowed its identity to Red-throated, Pacific, the very unlikely Arctic, or a small (arctic/interior) Common Loon, which would have been unusually early. Both the Common Loon and this bird were generally dark gray/near black above and white below. It quickly became apparent that this bird's head was not bulbous as would be expected for a Common Loon, so that could be ruled out. As it approached and it presented more in profile, its identification became more obvious. Besides being considerably smaller than the Common Loon, this bird was structurally more compact and streamline, with a trimmer bill and sleeker head, and shorter neck. The side of its neck was mostly dark and smoothly bordered by white, without interruptions or intrusions of white into the dark.

Smaller than nearby Common Loon with which it was traveling, but generally loon-shaped. The head was more streamlined, the neck shorter and the belly more trim than Common Loon.

Head had smoother profile than Common Loon and not as large relative to neck thickness, and was dark gray/near black through eye with small white chin/cheek patch. Neck was mostly dark on side with nicely defined dark/light interface at bottom of neck (in flight) which slanted upward toward body, exposing more white on neck toward body. There were no white interruptions or intrusions into this dark as in Common Loon.

Bill was intermediate between Common and Red-throated Loon, closer to Common in shape though generally more slim. Feet not noted other than as contributed to slightly more attenuated structure of entire bird compared to Common Loon.

Not noted - though probably same dark gray/near black.

Same as back

Dark above and long and pointed, appearing quite flexible in flight.

All white, except under tail not recalled. I also vaguely recall that white of flank did not rise high onto side of back/rump as might be expected for Arctic Loon, though that memory is imprecise and was not written.

Not noted

Distinguished from Common Loon by more compact and slender structure, more slender bill, relatively smaller and more streamlined head, and uninterrupted dark/light neck pattern. Distinguished from Red-throated Loon by thicker bill lacking chiseled upward lower mandible and flat upper, by well defined dark/light neck pattern (as opposed to diffuse and lighter, more neutral gray neck of juvenile Red-throated Loon), and white chin patch on otherwise near black face. Distinguished from much less likely Arctic Loon by smoother head and (vaguely recalled) white/black belly/flank line not rising behind wing.

Report written from memory and scant notes, although was only Pacific Loon I saw this past season and did not attend many lakewatches, so encounter remains reasonably fresh and memorable.