44 NORTH AMERICAN DTTCKS, GEESE, AND SWANS. 



as far north as Lake Erie and western New York. To the northward 

 of Chesapeake Ba}^ the numbers decrease rapidly until Long Island is 

 reached, where the bird is rare. It is hardly more than a straggler 

 in Massachusetts and is accidental in Maine, New Brunswick, and 

 Nova Scotia. It has not been recorded as yet from Newfoundland, 

 Lalirador, or the Hudson Bay region. 



The great flocks that formerly covered Chesapeake Bay are of the 

 past, but a few still winter on the coast of the Carolinas. Accidentals 

 are I'ecorded from the Bermudas, from Cuba and Jamaica, and one 

 from Guatemala. These seem to be all the records south of the Valley 

 of Mexico, where it is not rare in winter. The winter range extends 

 from this district and Mazatlan on the western coast, north to southern 

 Illinois, Colorado, Nevada, and southern British Columbia. 



Spring migration. — In February a few move north, bringing the 

 van the latter part of that month to about latitude 39° in the Missis- 

 sippi Valley, which is the northern limit of the species in mild winters. 

 Early March brings the species to southern Iowa. Average dates of 

 spring arrival are: Keokuk, Iowa, March 12; central Jowa, March 15; 

 southern Wisconsin, March 26; Heron Lake, Minn., March 28 (earliest 

 March 19, 1889); central Nebraska, March 14; northern North Dakota, 

 April 18; southern Manitoba, April 21 (earliest April 6, 1885). In 

 the interior of British Columbia eggs have been found May 21; in 

 North Dakota, May 18; at Great Slave Lake, June 4, and Fort Yukon, 

 June 3. 



Fall inigration. — In the day of the great flights to Chesapeake Bay 

 the gunners did not expect large Hocks of canvasbacks much before 

 the middle of November, but a small number appeared some time ear- 

 lier. For the last sixteen years the average date of the first arrival 

 at Alexandria, Va., has been October 21 (earliest October 15, 1903). 

 On the average canvasbacks have become tolerably common by Novem- 

 ber 8; in 1888 by -the last of October. These flocks cross Lake Erie 

 early in October, and the height of the shooting season there is toward 

 the end of that month. The first flocks cross the boundary to the 

 upper Mississippi Valley the last week in September and during the 

 month of October spread gradually south to the southern limit of the 

 range in the Valley of Mexico. Southern California is reached about 

 October 20. In 1895 the last were seen at Heron Lake, Minnesota, on 

 November 27. 



Aythya marila (Linn.). Scaup Duck; Broadbill; Blackhead; Bluebill. 



Breeding range.- — The principal summer home of the scaup in the 

 Western Hemisphere is northwestern North America, from northern 

 North Dakota, southeastern British Columbia, and Sitka, Alaska, 

 north to Fort Churchill, Great Slave Lake, Fort Reliance, Alaska, and 

 JKotzebue Sound; also throughout the whole Aleutian chain to the 



