Thursday, November 4, 2010

Tundra Swans

Tundra Swans (Cygnus columbianus), formerly known as Whistling Swan, breed in the high arctic tundra and winter on lakes and estuaries in the lower US.    A Eurasian subspecies, Bewick's Swan (C.c. bewickii) , occasionally shows up in North America - in fact, there was a Bewick's at Wascana Lake in Regina a few years ago which stayed long enough for most of us local birders to have a look at it.

The black bill shows a bit of yellow near the base under the eye - the amount of yellow is variable. 

Juveniles/immatures have a pinkish-orange bill, outlined with black.  They will lose their grey feathers at the first molt.

Overland migration is done at day or night, in long, trailing V-formations, often at very high altitudes.  This flock of 200-300 individuals was at a slough near Torquay, SK, for about two weeks, resting and feeding. 

Sometimes one will see swans with a pinkish or yellowish cast to their neck feathers.  This is due to various minerals in the water where they have been feeding.

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