GULLS 
223 
Typical adults with pearly grey back and black wing tips are likely to be confused 
in the east with the Black-backed and the Kittiwake (on the coast) and the Ring-billed; 
in the central provinces with the Ring-billed and the California; and on the west coast 
with the Ring-billed, the California, the Short-billed, the Glaucous-winged, and the 
Western Gulls. 
From the Ring-billed distinguished by being larger, having flesh-coloured (pink) 
instead of yellowish or greenish legs and feet, and a red spot on the lower mandible instead 
of a black band around the bill. Note, however, that in birds coming into maturity the 
remains of the black bill of juvenility often resemble the ring of the Ring-billed (See 
Figures 324 and 328). 
From the Black-backed by smaller size and grey instead of black mantle. 
From the kittiwake in being larger, the legs and feet flesh coloured instead of black, 
and the red spot on the lower mandible. 
From the California in having flesh-coloured legs and feet instead of pale greenish or 
yellowish and there being no black fleck in the red spot of the lower mandible (Figure 326). 
From the Short-billed in being larger, legs ana feet flesh-colour instead of yellowish, 
and the red bill spot. 
From the Glaucous-winged by black, instead of grey, wing tips. 
From the W estern by having a lighter coloured mantle, pearl grey instead of dark 
lead, and black on wing tips less extensive (Figure 323, compare with 322). 
The juvenile gulls are more difficult to distinguish and it will sometimes take the 
nicest discrimination to do so. The Herring Gull of the year is the darkest and most evenly 
sooty of any of the young gulls it is likely to be confused with. The Black-backed is 
noticeably larger and the dark colouring of the back is more broken and less even. The 
juvenile Kittiwake is entirely different, being largely white on back with prominent dark 
shoulder streak and a sharply defined dark terminal tail band. The Western resembles 
the Herring Gull closely in colour, but is of a bluer cast, and is less even in tone. The 
Glaucous-winged is appreciably lighter, the darkest shade being mouse-coloured instead 
of nearly black. The California is considerably lighter, w ith more white mixed in above 
and below. The Ring-billed is still lighter, being more white than dark below', shows 
indications of the pearly mantle even during the first autumn, and has a broad, suffused, 
dark terminal band instead of an all-dark tail. Between the dark, juvenile Herring Gull 
Figure 323 
Wing of typical Herring Gull; scale, }. 
with browm legs and bill and nearly black tail and wings and the light-coloured adult with 
flesh-coloured legs, red-spotted yellow bill, and black wing tips there is every gradation and 
it is only by careful attention to details that some of them can be separated. There is 
great individual and sex variation in size, and care must be taken in comparing this char- 
acter that due allowance is made for these sources of confusion. The following schedule of 
characters of the Herring Gull may assist in the separation of these birds. Compare with 
similar schedule under other species. Large gull about 24 inches. 
Evenly very dark; tail evenly dark; bill dark with flesh- 
coloured base, feet brownish or flesh (Figure 324a) First autumn 
Light; slightly clouded with dark; tail clouded near end; bill 
yellowish, with partial or complete ring; feet flesh (Figure 
324b) Immature 
Light; tail white; bill yellow with red spot; feet flesh. Eyelids 
and gape yellow or purplish pink .Adult 
Field Marks. Size anti general colour. Smaller than the Black-backed and mantle 
grey instead of black. Distinguished from the Kittiwake by larger size, presence of white, 
apical mirrors on primary tips; round instead of squarish, or slightly forked tail, and flesh- 
coloured instead of black legs and feet. Similar to the Glaucous- winged and larger than 
76916—151 
