ing on its crown, hindcrown, auriculars,

and hindnape. The head and neck ap-

peared otherwise whitish. Its mantle con-

sistently appeared about one shade of

gray darker than delawarensis at all

times, irrespective of viewing angle; this

difference was especially noticeable in

flight. The primaries at rest appeared

black, with white apical spots on each

visible primary tip. The tail and under-

parts were entirely white.

In flight, its wing tip showed more ex-

tensive white compared to delawaren.sis,

with large , white mirrors in the outermost

two primaries. The under-wings ap-

peared whitish except for the dark tip,

which also showed two large, white mir-

rors. These two white mirrors on its wing

tip, along with its darker mantle shade,

easily distinguished it from the Ring-

billeds in flight.

Identification: The combination of a

small and slim-looking bill, rounded head

shape, darker mantle, large white mirrors

on the outermost two primaries, and

smaller size when directly compared to

delawarensis eliminates other species.

Adult California Gull (L. californ.icus)

also has a darker mantle than Ring-billed,

but californ.icus is larger, with a longer

and heavier bill that usually shows both

black and reel markings. Compared to an

adult Ring-billed , the Mew Gull (subspe-

cies brachyrhyn.chus) is "distinctly clark-

mantled" with no overlap in mantle

shade (Tove 1993). More challenging is

elimination of the "Common Gull" (L.

can.us can.us).

During winter, Common Gull usually

shows an irregularly-shaped band near

the bill tip ; when present, this band often

separates yellow on the bill tip from

gray-green to greenish-yellow color on

the bill base. In contrast, the bill of

brachyrhyn.chus is completely dull yel-

low and unmarked, although some indi-

viduals may show a thin, dusky subtermi-

nal band in winter (Grant 1986, Tove

1993).

Compared to the Common Gull,

brachyrhyn.chus has more diffuse head

markings in winter, producing a "uniform

grey-brown head " (Grant 1986). Accord-

ing to Tove 0993), both mantle shade

and wing tip pattern of Common Gull are

intermediate between delawaren.sis and

brachyrhynchus. The mantle shade of

Common Gull is only slightly darker than

delawarensis. Common Gull shows a

broad black wing tip like delawaren.sis,

but has large white mirrors on its outer

two primaries like brachyrhyn.chus (Har-

ris et a/. 1989, Tove 1993). Photographs

of these two subspecies in definitive ba-

sic plumage are shown in Grant (1986),

Tove 0993), and Enticott and Tipling

0997).

Distribution: The Mew Gull breeds in

North America from western and central

Alaska, central Yukon, and portions of

Mackenzie, south to the Alaska penin-

sula, south-coastal and southeastern

Alaska, coastal and northern British Co-

lumbia, northern Alberta, and in north-

eastern Manitoba at Churchill (Godfrey

1986, AOU 1998). In migration and in

winter, brachyrhyn.chus is casual to acci-

dental in the interior of North America

and along the Atlantic Coast. The Com-

mon Gull (subspecies can.us) breeds in

Eurasia, and is casual to accidental in

ova Scotia, Greenland, Iceland, and

other Atlantic islands (AOU 1998). This

form (species?) may be responsible for

additional winter records of the Mew

Gull along the Atlantic Coast (Tove 1993),

although the AOU 0998) notes that all

specimens from eastern North America

are brachyrhyn.chus.

Extralimital reports of the Mew/Com-

mon Gull in North America have in-

creased dramatically since about 1988

(Svingen 1997). Several Mew Gulls were

found in nearby states during December

1998, at about the same time as the Canal

Park record. Two first-basic gulls were

discovered during CBCs in Iowa (Brock

1999), and Wisconsin had three records,

including two different individuals on the

12'11 and the 13'11 in Milwaukee (Granlund

1999). Minnesota now has three records

of adults (Pieper 1982, Svingen 1997) and

is long overdue for its first immature

Mew Gull.

Fa/11999

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