Cackling Goose (Ridgway's)
Species, Date, Time and Location Information
Cackling Goose (Ridgway's)
12/25/2013 1:48:00 PM
12/25/2013 2:07:00 PM
Duration (total time in view):
Location Not Listed
Along the South Platte River
Carl Zeiss 10x40 Bins and Canon 7D w/ 100-400 mm camera
Description of the Bird
This bird was observed along the South Platte River in the company of an aproximate 3500 Richardson's Cackling Geese. It is being submitted because it is a Minima, which is a rare subspecies in the state.
When compared to the Richardson's Cackling Geese this bird was significantly smaller, not much larger than a Mallard. The bird exhibitted the typical chestnut colored breast with obvious sheen to it. The back color showed feathers that were blue-gray at the base, leading into brown with a noticable pale terminal edging. Head shape was small and very round. Bill was extremely short and stubby. The bird was initially sleeping, but throughout my observation time it woke up and entered the river.
Similar Species Discussion
Other Cackling Geese Species and intergrades were considered.
Richardson's are larger, have a square shaped head, longer bill and paler chest. Most of the birds in the photos with this bird are Richardson's.
Taverner's are much larger (larger than Richardson's), have a sloping forehead with longer and bulkier bill and the chest is usually grayish instead of chestnut.
Aleutians are also much larger (larger or similar in size to Richardson's) with a less round head and longer bill. They generally show a gullar stripe and white ring around the neck, which this bird lacked.
The bird did not show any obvious signs of intergrade based on size, color and head/bill shape.
All indications are that this is a 'pure' minima.
I have extensive experience with Richardson's Cackling Geese, and moderate experience with Taverner's Cackling Geese. My experience with Minima is pretty limited, but includes a bird found in the winter of 2012/2013 here in CO and talking in depth with Steve Mlodinow about that bird. I do not have any experience with Aleutians except what I have read and discussed with Steve.
Notes made AFTER observation
Date Documentation Submitted
1/27/2015 7:49:00 PM
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