Verification of Unusual
Rec. # 2007-23
|Scientific name:||Branta hutchinsii|
|Date:||June 3, 2007; July 19, 2007|
|Length of time observed:||40 mins; 20 mins|
|Location:||Fish Spring NWR Pintail Unit; Fish Springs NWR Ibis Unit|
|Latilong:||39 52.654' N and 113 23.241' W; 39 52.991' N and 113 22.006' W|
|Distance to bird:||~100 meters; ~60 meters|
|Optical equipment:||10x42 Leica Binocular & B&L 60mm Scope with 22-40x eyepiece|
|Weather:||Full sunshine; Full sunshine|
|Light Conditions:||Bright with sun about 90 degrees to my view; Bright with sun at my back|
|Description: Size of bird:||About 1/3-1/2 the volume of a Canada Goose.|
|(Description:) Basic Shape:||Waterfowl shaped (large body, long neck)|
|(Description:) Overall Pattern:||Black/White (head/neck) and shades of Grey/White elsewhere|
|(Description:) Bill Type:||Black and stubby bill characteristic of waterfowl|
Field Marks and
On June 3, 2007 and again on July 19, 2007 I observed a very small goose
associating with moulting Canada Geese (Branta canadensis moffiti, Great Basin
Canada Goose) in the Pintail Unit and Ibis unit at FSNWR. I've been volunteering
monthly bird surveys (total
species and numbers) at the refuge for about two years running.
1. Size: The size was about 1/3-1/2 the volume of the hundreds of associating Canada Geese. Distinctly much smaller than the Canada Geese - without any reservations.
2. Head: The white cheeks on an otherwise black head was the same as observed on the associating Canada Geese. The forehead was more steep on the small goose compared to the Canada Geese.
3. Bill: The bill was notably smaller than the Canada Geese - about 1/2 the length. This again was very obvious.
4. Neck: The black neck was notably shorter (about 1/2 the length) of the Canada Geese.
5. Breast: plumage/coloration was very similar to that of the associating Canada Geese - not significantly darker or lighter.
6. Legs: Dark
7. Back/Tail: The primary tips were black and darker than the back. The back was a dusky black-grey.
8. My overall impression was of a midget (Cackling Goose) in the midst of giants (Canada Goose).
The most obvious field marks were the small size and short stubby bill.
|Song or call & method of delivery:||No vocalizations could be discerned for this bird on both sightings.|
|Behavior:||Loafing/Preening/Feeding in the company of hundreds of Canada Geese. Nothing unusual of its behaviour.|
|Habitat:||Freshwater Pools formed from control of water from ~7 springs on the refuge. The pools are mostly open water with very little emergent vegetation located in an otherwise desert environment.|
were they eliminated:
There are four recognized subspecies of Branta hutchinsii that are lumped under
the common name of Cackling Goose (reviewed by Sibley and others). The most
probable subspecies observed at Fish Springs is the B.hutchinsii hutchinsii
based on the plumages described and geographic restrictions.
Branta Canadensis parvipes (Lesser Canada Goose): This subspecies of Canada Goose is smaller than B.canadensis moffiti. My understanding is that the size differential of these two subspecies is subtle, not nearly as great as what I have observed/described above. The bird observed was too small for this subspecies of Canada Goose.
this & similar species:
I have observed the Branta hutchinsii hutchinsii (when it was still called
Richardson's Goose) in western New York (fall migration/late 90s) and in
Minnesota/Wisconsin (especially during
sping/fall migrations in the 80s/90s).
|References consulted:||Sibley's Bird Guide. Sibley webpage description of Cackling Goose.|
|Description from:||Notes taken at time of sighting|
|Observer's address:||178 N Main St. #55, Salt Lake City, UT 84103|
|Observer's e-mail address:||firstname.lastname@example.org|
|Other observers who independently identified this bird:||None. The bird was observed in areas behind restricting gates. Jay Banta/Richard Sims were both alerted to the species presence but I'm not sure they ever took the time to view the bird.|
|Date prepared:||August 10, 2007|
Presumably this was the same bird observed on June 3 and July 19 during my
monthly surveys at Fish Springs NWR. I also did not realize this was a writeup
bird until I was informed of this
status by Robert Sims (Fish Springs NWR employee)in late July, 2007.