Tuesday, December 29, 2015

The "Canada" Goose Challenge


Below are pictures of "Canada" geese, both Canada and Cackling. Which are which? Read on. 


a. Cackling Goose and Greater White-fronted Goose. Cacklers can look small, but some are larger than Specks. The bill of this Cackler looks a bit long and thin here, but part of that is the light and lack of focus. Because of the variation in size, bill length, and changes in posture that can make some birds look long-necked, some Cacklers invite confusion with Canadas. 11 Jan 2009, Thornwell, LA. 

b. Ditto for Bird B. This Cackler looks large, but a close look at this small image shows a stubby bill and angled head. 11 Jan 2009, Thornwell, LA. 

c. This bird shows a stubby bill with slightly concave "droop" at the tip and a blocky head that identifies it as a Cackler. 20 Feb 2011, Cameron Prairie NWR. 

d. The curved and sloping head and long slender bill is a dead giveaway for a Canada. 6 Feb 2010, Wright, LA. 

 e. The blurry photo makes the bill look thin, but not long. The shorter bill, steep forehead, and angular peak in the rear crown show this to be a Cackler. This is the same bird as in Photo C, but note the different look in the different posture. 20 Feb 2011, Cameron Prairie NWR. 


f. All of these birds show small stubby bills and angled heads--obvious Cacklers. 11 Jan 2009, Thornwell, LA. 

g. This view of the same bird from Photos C and E shows the same stubby bill and blocky-headed look as the birds in Photo F. This bird was injured and often looked longer-necked than this as it stretched out its neck to pull itself forward; see additional photos at 
http://losbird.org/lbrc/goosebbb.htm. The long-necked look caused speculation that the bird might be a Canada Goose, but closer study proved that it was indeed a Cackling Goose. 20 Feb 2011, Cameron Prairie NWR. 

For more information about Cacklers, and for information on separating Cacklers from Lesser Canada Goose, see Distribution and Identification ofCackling Goose (Branta hutchinsii)Subspecies by Steve Mlodinow et al.

No comments:

Post a Comment