Thursday, April 26, 2018

TUNDRA SWAN, REESOR POND, REESOR RD. & HIGHWAY 7, MARKHAM, ON, 4/26/18

   A Tundra Swan was posted as being at Reesor Pond on ebird, so on the way home from Cranberry Marsh we stopped off there.  Low and behold we sighted it.
   We can ID this swan as the Tundra Swan (Cygnus columbianus), rather than the very similar Trumpeter Swan by the following:
   - The U-shaped border on the forehead, rather than the V-shaped border of the Trumpeter Swan. 
      The U-shaped border can be seen in the first two photos.
   - The thin connection of the eye to the bill, rather than the broad connection of the Trumpeter Swan.
      Because of this, the eye is prominent in the Tundra Swan, as in these photos.
   - The curve at the gape, rather than the straighter edge of the Trumpeter Swan. This can be seen in 
      the last four photos.
   - A slightly concave bill, rather than the straight bill of the Trumpeter Swan.  You can see this in the
      the fourth photo.

   The Tundra Swan has two subspecies, the American or Whistling subspecies and the Eurasian or Bewick's subspecies.  This Tundra Swan is of the American or Whistling subspecies.  Most of this latter species have some yellow in their lores, however about 10% have all black lores, such as this swan.

   The Tundra Swan is a new species to our Photographic Life List, which now stands at 780.









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