The Least Tern 

 No. 289 



Brown's Least Tern 



A. O. U. No. 74. Sternula antillarum browni (Mearns). 



Description. — Adult in summer: A glossy black cap covering crown and nape 

 broadly, pushed back from forehead by frontal crescent of pure white, whose base 

 touches the bill and whose horns reach over the eyes, but do not cut off the black of 

 lores from that of crown; remaining upperparts pearl-gray slightly silvered on wing- 

 quills, except three outer primaries which are chiefly blackish, with abrupt white on the 

 inner half of the inner web; underparts grayish white. Bill yellow, usually tipped 

 with black; feet yellow with black nails. Adult in winter: Lores white; area of cap 

 restricted to sides of head and to nape; crown with black shaft lines; upperparts darker 

 gray with reduction of silver in wing-quills, and encroachment of white on cervix. 

 Bill blackish; feet duller yellow. Immature: Like adult in winter, but black and 

 white of head not so clearly defined, and pearl-gray of upperparts varied by lighter 

 tips; traces of dusky on tail. Young in August: Lores, forehead, and crown brownish 

 buffy; a dusky border through eye and around on nape; feathers of back and wing- 

 coverts dusky in lunate or horse-shoe-shaped or catenate markings, varied by buffy 

 centrally or on edges; primary coverts dusky with buffy edgings, and quills silvery 

 dusky; tail slightly emarginate, mottled buffy and dusky centrally with white edgings. 

 Bill brownish black, paling basally. Length of adult about 228.6 (9.00) ; wing 167.8 

 (6.61); tail 88.9 (3.50); its fork 44.5 (1.75); bill 27 (1.06); depth at angle 5.4 (.21); 

 tarsus 15.4 (.61). 



Recognition Marks. — Sparrow size as to body; of course appearing much larger, 

 but easily distinguishable as the smallest of the terns; black cap; yellow bill; forked tail. 



Nesting. — Nests in colonies — mere hollows in sand or beach shingle. Eggs: 

 2 or 3; pale olive-buff, spotted rather finely and sparingly with dark chocolate and 

 violet-gray. Av. size 30.5 x 22.35 (i-20 x .88); index 73.3. Season: June-July 

 (May 20-Aug. 12); one brood. 



Range of Sternula antillarum. — Both coasts of the United States and the Miss- 

 issippi Valley south, at least, to Venezuela. 



Range of 5. a. browni. — Pacific Coast of the Americas. Breeds north to Mon- 

 terey Bay, California, and winters south at least to Guatemala and probably Peru. 



Distribution in California. — Breeds in colonies on sand beaches north to 

 Monterey Bay. There are eight or ten regular breeding stations, and varying con- 

 ditions of back-water invite occasional nestings. Arrives April-June; leaves in Sept. 

 Latest record of occurrence, Nov. 14, 1914, Santa Barbara. 



Authorities. — Coues {Sterna antillarum), Proc. Acad. Nat. Sci. Phila., 1866, 

 p. 100 (coast of Calif.); McCormick, Bull. Cooper Orn. Club, vol. 1, 1899, p. 49 (Los 

 Angeles Co., breeding habits); McAtee, U. S. Dept. Agric, Farmers' Bull. 497, 1912, 

 p. 24 (food); Mearns, Proc. Biol. Soc. Wash., vol. xxix., 1916, p. 71 (Sterna antillarum 

 browni, new subsp. ; Pacific Ocean, San Diego Co., near Mexican boundary). 



THE DOVE is often held up to us as the symbol of architectural 

 indifference or of slovenly home-making, but the palm really belongs to 

 the Least Tern. House-building for the Tern has no other meaning or 



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