LONG-WINGED SWIMMERS 
47. Great-black-backed Gull. 
Larus marinus. 
Range. — North Atlantic on both the American 
and European sides; breeds from Nova Scotia 
northward and winters south to the Great Lakes 
and the Middle States. 
The largest of the Gulls (thirty inches long) 
and unlike any other. The mantle is dark slaty 
black, and the primaries are black with white 
tips. The bill is very large and powerful and 
Grayish buff 
quite strongly hooked. They are quite abundant 
birds in their range, and are very quarrelsome, 
both among themselves and other species. They 
do not breed in as large colonies as do the other 
Gulls, half a dozen pairs appropriating a small 
island to the exclusion of all other birds. They 
are very rapacious birds and live to a great ex- 
tent, especially during the breeding season, upon the eggs and young of other 
birds such as Ducks, Murres and smaller Gulls. They place their nests upon 
the higher portions of sandy islands. They are made of grasses and seaweed. 
The three eggs are laid early in June; they are grayish or brownish, spotted 
with brown and lilac. Size 3 x 2.15. Data. — South Labrador, June 21, 1884. 
Three eggs. Nest on a small island off the coast; of grasses and moss. 
Great Black-backed Gull 
Kumlien’s Gull 
18 . Slaty-backed Gull. — Larus schistisagus. 
Range. — North Pacific and Arctic Oceans. 
This Gull, which is similar to the Great Black-backed, but is smaller and has 
a lighter mantle, does not breed in any considerable numbers on the Ameri- 
can side of the Pacific. It nests in June on some of the islands in Bering Sea 
and probably more commonly farther onrth. They often nest in company with 
other species, placing their small mounds of seaweed on the ground on the 
higher parts of the islands. The full set contains three eggs of grayish or 
brownish color, spotted with dark brown or black. Size 2.90 x 2. Data. — Har- 
rowby Bay, N. W. T. Canada, June 11, 1901. Nest of grass, roots and mud and 
lined with dry grass; on point making into the bay. Collector, Capt. H. H. 
Bodfish. 
43 
