34 BULLETIN 107, UNITED STATES NATIONAL MUSEUM. 
large, densely populated colonies made it an easy matter to gather 
the eggs in large quantities, which were salted down in barrels of 
brine for future use, but this custom does not seem to prevail to 
any extent to-day. These two destructive agencies undoubtedly re- 
duced the abundance of the species considerably, but it is probably 
holding its own again now or perhaps even increasing where it is 
protected. 
Falit—tThe fall migration starts late in August and proceeds 
slowly. Throughout the northern portion of their breeding range 
the birds linger until driven out of the lakes by freezing; but from 
the southern portions of its breeding range the species never wholly 
disappears, although the individuals seen in winter were probably 
not bred in that vicinity. There is a coastwise movement as well as 
a southward migration in the fall; the species winters abundantly 
along the southern half of the California coast, as well as farther 
south, and in the lakes of the interior. 
DISTRIBUTION. 
Breeding range.—Western North America. East to central Mani- 
toba (Shoal Lake and Red River), southwestern Minnesota (Heron 
Lake), northern Iowa (Eagle Lake, Hancock County, and Clear 
Lake, Cerro Cordo County), and eastern Nebraska (West Point and 
Omaha). South to southern Texas (Lavaca and Bexar Counties), 
northern New Mexico (San Miguel and Rio Arriba Counties), 
northern Arizona (Stoneman’s and Mormon Lakes and near Flag- 
staff), and southern California (Escondido, San Diego County). 
West to the Sierras of California (also Bear Lake, San Bernardino 
Mountains, and Elizabeth Lake, Los Angeles County), probably 
eastern Oregon and eastern Washington (east of Cascade Mountains) 
and south central British Columbia (Kamloops). North to south- 
ern Mackenzie (Great Slave Lake). 
Winter rangeSouthward mainly west of the Rocky Mountains, 
particularly along the Pacific coast. East to Nevada (Carson City) 
and Texas (San Antonio). South to Guatemala (Lake Duenas). 
West to the Pacific coast; western Mexico (Guaymas), Lower Cali- 
fornia (off La Paz and Magdalena Bay) and California (entire 
coast). North to Washington (Nisqually Flats). 
Spring migration —Northeastward starting in April. Lower Cali- 
fornia: Colnett Bay, April 8; San Quentin Bay, May 9. Colorado: 
Barr Lake, April 14. Wyoming: Lake Como, May 4. Nebraska: 
End of April. Kansas: Last of April to middle of May. Missouri: 
April 9 to May 3 (formerly). Montana: Teton County, May 1. 
Fall migration—Southwestward across the Rocky Mountains. 
Montana: Custer and Davenport Counties, October 2. Idaho: 
Coeur d’Alene Lakes, October 9. Colorado: El ‘Paso County, 
