Verification of Unusual
Rec. # 2009-03
|Scientific name:||Branta hutchinsii|
|Date:||21 Mar 2009|
|Length of time observed:||15 minutes|
|Location:||Sam Fellows Road|
|Distance to bird:||~50 yards|
Nikon Sky and Earth spotting scope, Pentax Optio W30 digital camera
|Weather:||Sunny and warm (~70 F), breezy.|
|Light Conditions:||Mostly direct overhead early-afternoon light, sun occassionally obscured by clouds|
|Description: Size of bird:||Smaller than the Canada Geese with which it was associating.|
|(Description:) Basic Shape:||Goose shape|
|(Description:) Overall Pattern:||White-cheeked Goose pattern: brown body and wings, black neck and head, white cheek patches, white base of tail, black tail|
|(Description:) Bill Type:||Small stubby bill reminiscent of a Ross's Goose.|
Field Marks and
This goose was easily identified as a "white-cheeked goose" (Canada or Cackling)
by its brown body and wings, black tail, white tail base and undertail coverts,
black neck and head, and white cheek patches extending up from under the chin
onto the face. This bird had a smaller, stubbier bill than the Great Basin
Canada Geese and Lesser Canada Geese with which it was associating. Its neck was
shorter and stockier. Its head was smaller and more blocky (i.e. shorter from
the base of the bill to the back of the head and with more abrupt angles in the
profile). The culmen was straighter and shorter than the Canada Geese's, and
formed a more abrupt angle with the forehead. The forehead was steep and formed
a more abrupt angle to the crown. The breast was about as pale as that of the
Great Basin Canada Geese. The flanks were paler than the color of the wings.
Body size was significantly smaller than the Canada Geese in all dimensions
(shorter in total length, shorter in breadth, and smaller in volume). There was
no black "chinstrap" bisecting the white cheek patches under the throat.
(See photos. The Cackling Goose the right-most bird in each photo.)
|Song or call & method of delivery:||None known to come from this individual.|
|Behavior:||Standing or sitting in an agricultural field with a flock of 17 Canada Geese.|
were they eliminated:
This goose was identified as one of the smaller white-cheeked geese (Branta
canadensis parvipes or Branta hutchinsii) on the basis of its small size, short
bill, and small relatively short head (from bill to nape). Separating the Lesser
Canada Goose, Branta canadensis parvipes, from the larger two Cackling Goose
subspecies, Taverner's Cackling Goose (Branta hutchinsii taverneri) and
Richardson's Cackling Goose (Branta hutchinsii hutchinsii) can be difficult but
I believe this distinction can be made for this individual. The bill was shorter
and with a steeper, straighter culmen (less concave) than in Lesser Canada
Geese, and formed a more abrupt angle with the forehead. The head was also
shorter from bill to nape than in Lesser Canada Geese. Finally, although there
is some overlap in body size between the largest Taverner's Cackling Geese and
the smallest Lesser Canada Goose, this particular individual was smaller than
the smallest Lesser Canada !
Geese I have seen in Utah.
I believe this was a Richardson's Cackling Goose and will present the reasons for that belief by addressing each of the four subspecies of Cackling Geese:
B. h. minima: The bill was not as short and stubby as it would be on a Ridgway's Cackling Goose. The breast of this bird was paler than the flanks, a condition that is reversed in B. h. minima, and this bird did not have the dark purplish-brown sheen seen in minima.
B. h. leucoparia: Aleutian Cackling Geese have a white neck ring which is usually quite bold. In the field, this bird did not appear to have a white neck ring. In the photographs a very faint partial white neck ring is evident when the bird has its neck completely outstretched. This faint neck ring is only slightly distinguished from the pale breast. This faint neck ring is inconsistent with the bold neck ring of Aleutian Cackling Geese. Also, many B. h. leucoparia have a black gular stripe. This bird did not have a gular stripe.
B. h. taverneri: The breast of this bird was paler than the average Taverner's goose. The bill of this bird was smaller than most photos I have seen of B. h. taverneri. The head shape was inconsistent with B. h. taverneri, being blocky with a flat crown and a peak at the rear of the crown where the head again had a relatively abrupt angle down to the nape.
B. h. hutchinsii: I beleive this was a Richardson's Cackling Goose. First, the head was angular and blocky (but small). This is evident in the photographs, but photographs can be misleading as posture changes and I can confirm the small, blocky head of this bird from fifteen minutes of observation in the field as well. Also, the head of this bird had a peak towards the rear of the head. The breast of this bird was about the same shade asthat of all of the Great Basin and Lesser Canada Geese it was associating with.
this & similar species:
|I have seen tens to hundreds of thousands of Canada Geese around the continent. I have seen hundreds of Cackling Geese in Washington, where they commonly overwinter and where I used to live, and several in Utah.|
Mlodinow et al. 2008. Distribution and Identification of Cackling Goose (Branta
hutchinsii) Subspecies. North American Birds 62:344-360.
Plus the webpages cited in record 2008-35.
|Description from:||From memory|
|Observer:||Ryan P. O'Donnell|
|Observer's address:||1098 Crescent Drive, Logan, UT 84341|
|Observer's e-mail address:||Ryan@biology.usu.edu|
|Other observers who independently identified this bird:||Steve Carr and Craig Fosdick.|
|Date prepared:||22 Mar 2009|
|Additional Comments:||One other possible Cackling Goose was seen in this flock, but the flock was flushed before a confident identification could be reached on this second bird and the few photos I took do not show the relevant features (bill shape, head shape, etc.) well enough for a confident identification.|