Documentation of Cackling Goose (Ridgway's)
2015-014

Observer Information

Reporter:  Cathy Sheeter  2245 S Waco St,   Aurora, CO  80013
E-mail:  crias@yahoo.com
Other Observers: 

Species, Date, Time and Location Information

Species:  Cackling Goose (Ridgway's)
First Date/Time:  1/27/2015 4:58:00 PM
Last Date/Time:  1/31/2015 10:12:00 AM
Duration (total time in view):  23 minutes on 1/27, 17 minutes on 1/31
County:  Denver
Specific Location:  City Park
Number:  1
Age:  Adult
Sex:  Unknown
Plumage:  Other/Unknown

Habitat

City Park - on ice/water on the 27th, on grass feeding on the 31st.

Viewing Conditions

Optics:  carl zeiss conquest hd 10x42 binoculars and sony a77ii camera with tamron 150-600 mm lens
Distance:  27th - 150 feet; 31st 25 feet
Light:  31st - Dim; setting sun; 31st- overcast

Description of the Bird

Jan. 27 - I initially ovserved this bird swimming with another Cackling Goose.  I noticed it right away for its small size, dark chest, and strongly patterned look to the back.  Upon closer look the bird was consistant with an adult Ridgeway's Cackling Goose.  It showed classic small round head shape, short stubby bill, a small size (smaller than Richardson's).  The color pattern showed a chestnut breast with sooty or purplish base to the neck.  The wing coverts appeared heavily patterned with a blue-gray base, darker sub-terminal band and thick pale outer edge.  My photos on the 27th failed to capture the color very well, as it was quite dark and I had to take the photos at ISO 4000, but they were seen well with my scope (Eagle 60-80x).


I returned to City Park on 1/31/15 with Ted Floyd's CFO walk.  Although the goose was not found as part of that group walk I refound it after the class broke up.  It was with a flock of around 300 other Cackling Geese (both Taverner's and Richardson's represented).  I was able to get better photos and a closer look at the goose.  All of the traits I saw on the 27th were the same as on the 31st.  I was able to match up the cheek pattern in my photos to confirm it was the same bird.

Similar Species Discussion

It was obvious that the bird was a Cackling Goose and not a Canada Goose from the tiny size, short neck and very tiny bill.


Elimination of other Cackling Goose subspecies as follows:


Richardson's: The bird was obviously smaller in size (since Richies were right there to compare it to), with a round rather than rectangular head shape.  The bill was quite a bit stubbier when compared to Richies.  The breast was also much bronzier in color.  
The back was much more patterned.


Taverner's: Again size (Tav being usually slightly larger than Richie) was obvious.  The rounder head shape - the bird lacked the sloping forehead of Taverner's.  The chest was more of a chestnut brown than the more typical Tav gray-brown.  The wing coverts was much more patterned.


Aleutian: This bird did not show any indication of a white neck ring.  Aleutian are also larger with a longer bill and with a head shape that goes more straight up from the bill, not as round as this bird.  The back showed much stronger patterning.  This bird did show a gullar stripe, but no other traits that would support Aleut.

Resources Used

I am familiar with the look of this subspecies from personal experience and reading: http://www.utahbirds.org/RecCom/IDhelp/Cackling_Goose-NAB.pdf among other articles on Cackling goose subspecies ID.  I felt confident based on this birds being an adult and the textbook color pattern, size and shape that I did not need to consult additional experts in this case.

Previous Experience

This is the third minima that I have found in Colorado.  I have looked extensively at photos of this ssp taken in the Pacific.  I have extensive experience with the more expected Cackling Geese (Richardson's and Taverner's) of Colorado as well as with Canada Geese.

Notes

Notes made AFTER observation

Date Documentation Submitted

2/1/2015 8:49:00 AM
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Location Map

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