ML619221225

Age

Not specified

Sex

Not specified

Observation details

McNab spotted this bird sitting on the water approximately midway between the 279-fathom Bank and the Lausen Sea Mount, and about 26 kilometers southwest of Dana Point (33° 19’ 33.2” N, 117° 56’ 35.2” W). We then spent an extended period of time following after this bird as it swam at the surface and dove repeatedly. Although this bird raised-up to flap its wings on several occasions, it never took flight or even attempted to do so. This bird was a relatively large, heavy-bodied alcid that did not appear as significantly larger than a nearby Rhinoceros Auklet as it did different in shape, given its massive bill, large head, and notably plump body. The laterally compressed bill was notably deep at the base, and with the culmen curving strongly downward to a broadly pointed tip. I cannot recall seeing this bird head-on, so I was unable to see clearly just how wide the bill was, but my impression was that it was relatively narrow. When seen from the side, the bill did not appear much longer than it was deep at the base. I noted little or no forehead, with the base of the bill merging with a crown that appeared only subtly curved, if not somewhat flattened, as it extended back to the smoothly curved nape, all on a head that was proportionately large for the bird’s size. The neck was short and inconspicuous, and as noted above, the body was notably plump, full-chested, and sitting relatively high on the water. I was unable to discern the structure of the closed wings, but when the bird flapped the wings, I thought the spread wings were slim, seemingly relatively short, and tapering to somewhat pointed tips. I did not think the feathers were strikingly worn or with obvious gaps. I did not see an obvious tail, but I was unsure if this was because it was short, or instead, because the tail was held on or under the surface. I was also unable to see clearly in the field the belly, legs, or feet on a bird that we saw exclusively either sitting on the surface or diving; however, my photos do seem to show webbed feet just under the surface. This bird was a dull black in color almost throughout. Unlike an adult in alternate plumage, such as the one that was seen the previous day, this bird had neither the broadly white face nor the conspicuous golden tufts, but instead, it had a somewhat diffuse blaze that extended from the eye back across the superciliary region toward the nape. The forehead and crown were blackish. My photos show a few wirelike projections extending back from the nape and curving downward, but I was unable to see these in the field. Apart from the white in the face and the golden “tufts,” I thought the rest of the plumage was dull black from the throat and neck down through the breast, and likewise down the back and sides of the neck, and across the back, scapulars, and whatever I could see of the closed wings, rump, and tail. I was unsure to what degree I could see the flanks, undertail coverts, rump, tail, or belly. The distal half of the bill was a bright, reddish-orange color, and contrasting sharply with a dusky base to both mandibles. I had a hard time seeing the color of the eyes in the field, but my photos show the irides to be whitish and contrasting conspicuously with dark pupils. I was unable to see in the field the colors of the legs or feet, but my photos appear to show pale-yellowish feet just below the surface.

Technical information

Model

Canon EOS R7

Lens

EF100-400mm f/4.5-5.6L IS II USM

ISO

400

Focal length

400 mm

Flash

Flash did not fire

f-stop

f/6.3

Shutter speed

1/2500 sec

Dimensions

1406 pixels x 1053 pixels

Original file size

475.42 KB