ML407146371

Age and sex

Immature Unknown sex - 1

Observation details

*Rare. Fantastic bird for Marin. Maybe the 4th county record (in eBird). Third winter individual picked out of the masses a little earlier today by A. Merritt (legendary status = firmly cemented). The bird was seen almost immediately upon my arrival since numerous other birders were already on it. Viewed primarily from San Rafael Ave., just SW of Winward Rd. The bird was foraging on the mudflats for the entire duration of the visit, and eventually worked its way SSW to within 30 or so feet of a few of us, allowing great looks. Overall, fairly close to a California Gull in size, and separated from CAGUs in the field primarily by mantle color (a few shades darker). Structurally, appeared longer-winged. Given color of mantle and range, this is a presumed L.f. graellsii. Somewhat of a textbook 3cy LBBG with; dark streaking on head and neck; light irides; bill yellow proximally and dark distally with a light tip; adult mantle; brownish coverts; darker brown/black primary coverts (and even the base of outer secondaries as described by S.N.G.H.); almost no white in tips of outer primaries; perhaps some retained median coverts; very slight dark markings in the tail. Most of this is noticeable in the open-wing/flight photo ML407146301; legs somewhat dull pink/yellow, but difficult to discern (not adult yellow). The bird called a few times as well, but the vocalizations didn't stand out among the numerous other gulls. Amazing bird, and fun to study.

Technical information

Model

ILCE-9

Lens

FE 200-600mm F5.6-6.3 G OSS

ISO

4000

Focal length

600 mm

Flash

Flash did not fire

f-stop

f/6.3

Shutter speed

1/2500 sec

Dimensions

2890 pixels x 1927 pixels

Original file size

3.47 MB