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The Canvasback
CANVASBACK ( Aythya valisineria ) 19 - 24"
A very white looking duck with a long sloping head profile. Rusty-red
head and neck, black breast, long blackish bill. Looks front-heavy.
The Canvasback is a species of the Diving Ducks (Aythyinae), which
will be arriving in late February at Utah's state and federal refuges in
great numbers on their migration north to nesting areas. The spring migration
numbers about one third to one half of the fall migration.
This species is found in all four North American flyways, but is common in
the Pacific and Atlantic. The canvasback is to eastern hunters what the
pintail is to the western. Once in great numbers, its current population,
especially in the Atlantic Flyway, is down to two percent of the country's
duck population according to an article in the Deseret News of Jan. 11,
1974. The article also says that the canvasback and redhead ducks, frequently
associated together, cannot be hunted in 1974 in the Atlantic Flyway, and
only in limited numbers in the other three flyways. "Many factors are
contributing to this decline ... the Fish and Wildlife Service is aware of
several factors ... (and) a $200,000 study of canvasbacks is being performed
by the Service at research centers in Maryland and North Dakota."
The canvasback derived its specific name valisineria from one of its
preferred foods, the water celery, a Valisineria species in its
eastern habitat which gives the flesh a succulent flavor. In the Northwest,
where the duck includes shellfish and rotting salmon in its diet, the flesh
is unpalatable. This duck is easily identified by its size (19" to 24"),
the long sloping line of combined head and dark bill, and the whitish to
grayish backs. The head of the drake is dark rusty red, and breast is black,
while the female has a paler reddish brown head and breast. At a distance,
when sitting low in water, the drakes appear mostly white. The voice of the
drake is a croak or a growl, while that of the female is a
quack. The birds are powerful and noisy flyers, and often take to
considerable heights, flying in irregular lines or V-formations.
The canvasback breeds from central Alaska, east to southeast Manitoba and
south to northern California, then eastward; occasionally in northern Utah,
northern Colorado, Nebraska and central Minnesota, with greatest numbers in
the prairies of central Canada and United States. The wintering grounds
are south to central Mexico, Gulf States, and some to Guatemala and Cuba
wherever there is fresh water or sheltered estuaries.
The nest is well hidden in a slough or pond near a large lake. It is built
above high water line, in a bed of cattails or rushes. The female weaves
a platform of plant materials and lines it with her down. She lays and
incubates alone, seven or more greenish gray eggs for 22 to 23 days. The
young are ready for flight within two or two and a half months. The drake
joins other males during this time, which is also the adults' molting
period.
Food is eighty percent vegetation, largely aquatic plants, including water
celery and pondweed. The animal part of the diet includes mollusks, insects,
and fish.
-- by Marie L. Atkinson
REFERENCES:
Field Guide to Western Birds
Roger Tory Peterson
National Geographic -- Diving Ducks
S. Dillon Ripley
Key to North American Waterfowl
Stephen R. Wylie & Stewart S. Furlong
AUDUBON Illustrated Handbook of American Birds
Edgar M. Reilly, Jr.
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