234 
CHARADRIIFORMES 
62. Sabine’s Gull, la mouette ou mauve de sabine. Xenia sabini. L, 13-50. 
Similar to Franklin’s or Bonaparte’s Gull, especially the latter, but smaller and with wings 
largely black, a dark slate-grey hood bordered basally by a black line making a narrow 
rine around the upper neck, cutting sharply against a white lower neck (Figure 343). 
Distinctions. The Arctics. Like a small Franklin’s Gull, but with a grey, black- 
bordered hood instead of a black one. Black legs and feet and black bill tipped with 
yellow. Tail forked, outer feathers about 1| inches longer than middle ones (Figure 343). 
Juvenile darker and more evenly sooty above than either Franklin’s or Bonaparte’s 
Gulls. Tail forked. In all plumages the wings seem characteristic, the primaries and 
wrist are almost solid black, the secondaries very largely solid white. 
Figure 343 
Specific details of Sabine’s Gull; scale, \. 
Figure 344 
Wing of Sabine’s Gull. 
Field Marks. .Should be an easy bird to recognize in life, a small dark-hooded gull 
with forked tail, intensely black primaries and wrist contrasted with a great white area 
of secondaries (Figure 344). It is, however, too rare, except in the far north, to be accepted 
as a record on field observations alone. 
Nesting. Usually on the moss of the boggy edges of tundra pools. 
Distribution. The Arctic regions, only occasionally wandering down into southern 
sections. We have stray records for northern Manitoba, northern Saskatchewan, and 
southern British Columbia. 
One of the most delicately beautiful of the gulls, but too rare to receive 
more than passing mention. 
Subfamily — Sterninae. Terns 
General Description. The terns, or Sea Swallows as they are sometimes called, are 
smaller, lighter, and of more graceful build and habit than the gulls. 
Distinctions. The bill — lighter, and more slender than that of the gulls (See Figure 
316, page 218) — and the forked tail are characteristic of the terns and will usually separate 
them without difficulty. All Canadian species have a more or less forked tail and all but 
one (the Black Tern) in summer adult plumage have a sharply defined black cap. The 
forking of the tails of young birds, though beginning to show early in their development, 
does not reach its maximum until after they leave for the winter; hence, through the 
summer and autumn, many individuals will be seen with much smaller forks than the 
given measurements indicate. 
Field Marks. The greater lightness of action on the wing and constant and rapid 
aerial evolution; the fact that terns constantly dive from the wing, and the habit of com- 
monly turning the bill straight down towards the water instead of carrying it on a lino 
with the body, are characteristic. The forked tails and black caps are also good recognition 
marks for adults. 
Nesting. Whereas gulls seem to prefer rocky shores upon which to breed, the terns, 
except Forster’s and the Black, favour sandy beaches or bare rock surfaces, laying their 
eggs in a smooth circle of pebbles without other nest preparation. 
Distribution. As a subfamily, terns are more southerly in distribution than gulls, 
though at least one species, the Arctic Tern, has been found as far north as land occurs. 
All our species migrate, none remaining in Canada during the winter. 
