ML616121380

Age

Not specified

Sex

Not specified

Observation details

Second cycle on A13. Bulky, barrel-chested, dumpy large gull with a distinctly pale eye, strong "mascara" (i.e., bold dark smudging immediately around the eye), very pale greater coverts forming whitish panel, patches of dark adult gray coming in on mantle and scapulars (which despite harsh light appeared relatively dark in the field, certainly substantially darker than HERG, THGU, GWGU, and Cook Inlet, all of which were present for comparison), tertials with dark centers and sharply contrasting whitish tips, primaries and rectrices black, pink legs (hard to assess leg color more specifically in poor light), moderately heavy and longish bill not bulging toward tip and appearing all black, including basally. Structurally distinct from Western—gonydeal angle very slight, not relatively acute (forming bulbous bill tip) as in Western, and head blocky and with a very flat crown, not neatly rounded as in Western. Small-headed pot-bellied shape with prominent chest projection dissimilar to Western also; even a Western with a very full crop should not show such a massive heavy-bodied profile. Eye much paler than expected even in wymani WEGU (especially one sufficiently retarded to show an apparently all-black bill late in its second cycle), greater covs more evenly whitish, "mascara" stronger, etc. Structurally distinct from Herring as well—general body shape thickset, heavy, and stocky, with blockier head (flatter crown, shallower forehead, sharper angle at nape and back of crown), and less attenuated appearance to rear end (perhaps contributed to by slightly shorter/broader primary panel?). Also inconsistent with 2cy Herring are uniform pale greater covs, relatively dark adult gray on mantle (clearly darker than nearby smithsonianus Herring in direct comparison), heavy eye-mask, and apparently all-dark bill, including base. To us, mantle color did not appear pale enough (i.e., near GWGU shade) to raise concern about Commander Gull, and—importantly—primaries and rectrices (despite its being late in the season, when these are often bleached pale in large gulls, especially rather worn birds like ours) appeared completely black. See https://ebird.org/checklist/S131153641 for one example of an acceptable pale-mantled 2cy Slaty in CA; many such birds are photographed in the ordinary range. Comments from Dessi: Overall size/ shape— appeared slightly larger than nearby Herring Gulls. Overall appeared small-headed, big-bodied, and barrel chested. Whenever it stood up this bulging chest certainly stood out from the nearby Herring Gulls. Bill— entirely black, straight, and medium length. No bulging tip like seen in a Western or GW Gull. Most of the second-cycle Herring Gulls nearby had a pink base to the tip. Eye— certainly pale, but not gleaming. There were some dark markings around the eye, otherwise the head was white. The head shape appeared more square than adjacent Herring Gulls, with a very shallow sloping forehead and a slight bulge at the nape. This contrasted with the more round heads of the nearby Herrings. Mantle— there were adult feathers coming in on the upper mantle. The color of these feathers was difficult to judge as the lighting was poor, but they were certainly darker than the mantle feathers of nearby Herring and Glaucous-winged Gulls in the same light. Coverts— both the median and greater coverts were heavily bleached and appeared white. A few greater coverts had brownish centers to them, but were still heavily bleached. Tertials—very dark tertials (similar to the color of the primaries) with white tips. These tertials contrasted greatly with the bleached greater coverts. Primaries— black, suggesting no GW Gull parentage. The primaries appeared truly black both at rest and when it flapped a couple times. Tail— black, again suggested no GW Gull parentage Underparts— appeared white, except for a few dark markings around the neck area Legs— pinkish, similar in color to nearby Herring Gulls Comments from Alvaro: “Overall it looks fine, good, no issues for a second cycle Slaty-backed. With the caveat that hopefully the photos are not misleading.”

Technical information

Model

iPhone 13 mini

Lens

iPhone 13 mini back dual wide camera 5.1mm f/1.6

ISO

40

Focal length

5.1 mm

Flash

Flash did not fire

f-stop

f/1.6

Shutter speed

1/204 sec

Dimensions

3024 pixels x 4032 pixels

Original file size

1.99 MB