POMARINE JAEGER 
36. Stercorarius pomarinus. 21 inches. 
Jaegers are more slender in form than the Skuas, but 
like them are piratical in their habits, preying chiefly 
upon terns. Off Chatham, Mass., I have often watched 
them in pursuit of the graceful terns, but, excellent 
fliers as the latter birds are, they were always over- 
taken and forced to drop the fish that they carried, and 
the jaeger would rarely miss catching it as it fell. This 
species has two color phases independent of sex or age. 
In the light plumage the top of the head is black; rest 
of the upper parts and the under tail coverts brownish 
black; underparts and bases of primaries, white. Dark 
phase,—Entirely blackish brown except the white shafts 
to wing feathers and bases of primaries. In any plu- 
mage they can be distinguished from the other species 
by the rounded, lengthened central tail feathers. 
Nest.—A hollow in the ground in marshy places. The 
two eggs are olive brown spotted with black. 
Range.—Northern hemisphere, breeding north of the 
Arctic Circle; winter from Mass. southward. 
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