Rare Bird Report 5-A-08
IDAHO BIRD RECORDS COMMITTEE
RARE BIRD REPORT FORM
SPECIES:
Whooper Swan (Cygnus cygnus)
HOW MANY:
1 adult
REPORTER:
Craig Fosdick
PO Box 443,
Logan, Utah, 84323-0443 Phone: 208-860-6011
REPORTER EMAIL:
craig.fosdick@gmail.com
OTHER OBSERVERS:
Jay Carlisle originally found the bird in ?November?
I observed the bird with Justin Barrett.
DATE REPORT PREPARED:
1/28/09
DATE SIGHTING OCCURRED:
1/25/09
LOCALITY OF OBSERVATION:
Snake River at Bell Rapids Rd/Owlsey Bridge, Hagerman, Twin Falls/Gooding County line, Idaho.
HABITAT:
River. Open, not frozen.
CONDITIONS:
Cold, windy, snowing hard. 25°F. Bird observed at 150–200 m using Leica 8x50 binoculars and Leica scope. Bird was identifiable without optics. Sun was high and to right of observers and bird, but it was overcast, so sun not visible.
DID YOU TAKE NOTES?:
Yes, during the observation
DID YOU CONSULT FIELD GUIDE OR OTHER REFERENCES?:
Yes, during the observation
WHAT GUIDE(S) OR REFERENCE(S) DID YOU CONSULT?:
The Sibley Guide to Birds, 2000. Three days after sighting, on 1/28, consulted National Geographic Field Guide to the Birds of North America, 4th edition for information on eyering coloration.
DESCRIPTION:
Large white swan, apparently identical in size to Trumpeter Swans it was associating with. “Straight slope” formed by the angle of the bill and the forehead, as in a Trumpeter Swan, but yellow patch present on the proximal half of the upper bill. Yellow also present on proximal half of lower bill, but only in center; yellow on lower bill not visible from side (see accompanying photos). No yellow eyering, as shown in Sibley and National Geographic. Bird was same size (approximately) as both the two Mute Swans and 15 Trumpeter Swans also present. Legs black, feet and lower legs not visible.
BEHAVIOR:
Swimming and actively feeding. Spent most of time putting head in water and foraging. Did not fly or vocalize; no apparent interactions, aggressive or otherwise, with either Mute or Trumpeter Swans.
HOW AND WHEN DID YOU POSITIVELY IDENTIFY THE BIRD, AND WHAT CLINCHED THE IDENTIFICATION FOR YOU?
Identification determined as soon as the bird was seen. Large white swan with “straight slope” formed by the angle of the bill and the forehead, as in a Trumpeter Swan, but yellow patch present on the proximal half of the upper bill. Whooper Swan otherwise appeared to be a Trumpeter Swan, except that Trumpeter Swans do not have yellow on the proximal half of the upper bill.
HOW DID YOU ELIMINATE SIMILAR SPECIES, AND WHAT WERE THEY?
Readily differentiated from the nearby Trumpeter Swans by the large yellow patch present on the proximal half of the upper bill; Trumpeter Swans do not have yellow on the proximal half of the upper bill. Mute Swans, which are approximately the same size as both Trumpeter and Whooper Swans, have pale dull pinkish (first fall birds) or orange (adults) bills. Also, Mute Swans do not have the “straight slope” formed by the angle of the bill and the forehead that Whoopers (and Trumpeters) have. Tundra Swan eliminated on basis of different bill and head shape, smaller size (70-80%? smaller than Whooper or Trumpeters). Tundra Swans do have yellow on their bills, but in most cases the yellow is restricted to the lores. Also, Tundra Swan bill shape is very different than Whooper or Trumpeter Swans; Tundra Swan bills angle down, then extend forward, so that they do not have the “straight slope” formed apparent on Whoopers and Trumpeters.
EXPERIENCE WITH THIS SPECIES (AND SIMILAR SPECIES):
I have previously seen a Whooper Swan of questionable origin in upstate New York (9 February 2002; Westport Boat Launch, Essex Co., NY), the origin of which is addressed in Terry McEneaney’s paper in North American Birds (2004; Vol 58(2):301–308). Have probably seen about 60-80 Trumpeter Swans, and hundreds if not thousands of Tundras and Mute Swans.
GENERAL BIRDING EXPERIENCE:
24 years of birding experience. Expert.
WERE PHOTO(S), VIDEO, AND/OR AUDIO OBTAINED BY YOU?:
Photo
