The Black Tern 
No. 290 
Black Tern 
A. O. U. No. 77 . Chlidonias nigra surinamensis (Gmelin). 
Description. — Adult in summer: Head and neck all around, glossy black, 
shading into sooty black of underparts; the crissum white and the edges and lining of 
wings white or pale pearl-gray; upperparts plumbeous, darker on upper back, where 
it blends through slate with black cervix; bend of wing white; primaries inclined to 
silvery on exposed webs after the first, the inner webs, however, dusky, lightening on 
the inner half, and the shafts white; tail slightly forked. Bill and feet black. Adult 
in winter: Lighter, the black replaced by white, save on back of head, orbits, and 
auriculars, where obscurely persistent; upperparts deep pearl-gray. Immature: Like 
adult in winter, but upperparts more or less tinged and tipped with brownish, and sides 
washed with grayish. Length 228.6-260.4 (9.00-10.25); wing 203.2-215.9 (8.00-8.50); 
tail 76.2 (3.00); bill 26.4 (1.04); tarsus 17 (.67). 
Recognition Marks. —Towhee to Robin size, but appearing about Killdeer 
size; sooty black and plumbeous coloration distinctive in breeding plumage; dark 
pearl-gray of upperparts with black bill (and feet), with small size sufficiently distinctive 
at other seasons. 
Nesting.— - Nests in loose colony fashion, each a truncated cone of twisted 
grasses or bent sedged, placed on ground in marshes or on drifting reeds, old grebe 
nests, or anything which offers support on the surface of the water. Eggs: 3 (4 of 
record); olive-buff to dark olive-buff, or cinnamon-buff to clay-color and tawny olive, 
heavily spotted and wreathed, or strikingly blotched, or even rough-banded, with 
black or reddish black (dark bister to dark Vandyke brown). Av. of 15 sets in M. C. 
O. coll.: 33.5 x 23.9 (1.32 x .94); index 71. Season: c. June 1st; one brood. 
Range of Chlidonias nigra. —Europe and temperate North America, south in 
winter to Africa (both coasts) and South America. 
Range of C. n. surinamensis. — Breeds in interior North America from south¬ 
western British Columbia, Mackenzie (Great Slave Lake), and southern Keewatin, 
southeastward to eastern end of Lake Ontario, thence southwestward through northern 
Ohio, Kansas, etc., to southern California. Of general occurrence near water during 
migrations, but especially coastwise, south through Mexico and Central America to 
the Guianas, Peru and Chile. 
Distribution in California. —Breeds commonly at suitable places in the 
interior, both east and west of the Sierras, and as far south as Buena Vista Lake (Lin¬ 
ton) and possibly Lake Elsinore (Heller). Of rare occurrence coastwise above Point 
Conception, but abundant during migrations in the Santa Barbara sector. 
Authorities. — Cooper ( Ilydrochelida plumbea), Proc. Calif. Acad. Sci., vol. ii., 
1861, p. 122 (headwaters of Mojave River); McAtee, U. S. Dept. Agric., Farmers’ 
Bull. 497, 1912, p. 24 (food); Tyler, Pac. Coast Avifauna, no. 9, 1913, p. 14 (San Joaquin 
Valley; breeding habits). 
IRRIGATION has caused the desert of the West to blossom as the 
rose. If that were all, we could be thankful for roses—and such roses! 
California roses, of course! But when to roses are added such practical 
1460 
