Chestnut-backed Chickadee

Chestnut-backed Chickadee, Newport, Oregon on 7 March 2010 by Greg Gillson.

 

Earlier in the month I spent the weekend at Newport, Oregon. Around the Marine Science Center I found this Chestnut-backed Chickadee (see previous post about this species).

It was a cloudy morning, as it often is along the Oregon coast. I shot this at ISO 800 equivalent, which gives it a bit of grainy appearance.

The Chestnut-backed Chickadee was described to science by its discoverer, John Kirk Townsend, in 1837. He obtained the type specimen during a trip to the Oregon country in 1834-1836. He didn't keep very accurate notes about where he collected each species. His collection location for the Chestnut-backed Chickadee he shot was entered as the "forests of the Columbia River." So the type location of Chestnut-backed Chickadee became Ft. Vancouver, Washington, where he spent the most time after he arrived.

Townsend's lackadaisical note-keeping also produced some odd records. For instance, he named several southern seabirds from Oregon. These, no doubt, came from ocean trips to South America he made about the same time.

Glaucous-winged Gull

Glaucous-winged Gull, at sea off Newport, Oregon on 6 March 2010 by Greg Gillson.

 

In the 1953 book, Birds of Washington State, Jewett, Taylor, Shaw, and Aldrich described the southern edge of the breeding range of Glaucous-winged Gull as Destruction Island, Washington, nearly due west of Mt. Olympus on the Olympic Peninsula. Likewise, that island about 4 miles offshore was the northern edge of the breeding range of the much darker Western Gull.

Today the situation is much different--for the Glaucous-winged Gull, anyway. This pale gray gull, with upper wingtips concolorous (in all plumages) with the rest of the upper wing and back, now breeds south to the central Oregon coast.

The range expansion created a new population dynamic. In the 200 miles where the two ranges now overlap, Glaucous-winged and Western Gulls hybridize extensively. The fertile crosses and back-crosses span the entire spectrum from looking quite pale like Glaucous-winged Gull to very dark like Western Gulls. The hybrid swarm is often referred to by birders in the Pacific NW as "Olympic Gulls." In fact, many birders along the central Washington coast do not try to differentiate them, even when surveying seabirds.

In winter, Glaucous-winged and hybrid gulls are common along the coastline south to San Francisco or farther, in the Puget Sound area, and inland in the larger towns west of the Cascades, and increasingly as vagrants across North America. In contrast, "pure-looking" Western Gulls are rare away from the immediate coast.

As with most larger gulls, they are omnivorous, eating anything they can swallow. They are common in garbage dumps and parking lots of fast-food establishments.

Jackson Bottom birds, March 20-26, 2010

A new migrant this week was SAVANNAH SPARROW. Several were noted starting March 24. On March 26 came the first report of COMMON YELLOWTHROAT.

Other migrants increased in numbers, including TREE SWALLOWS, RUFOUS HUMMINGBIRDS, GREATER YELLOWLEGS, and TURKEY VULTURES.

A EURASIAN WIGEON was reported March 20 and a PEREGRINE FALCON put in an appearance on March 26.

BUSHTITS are building nests now. The GREAT HORNED OWL chick is about 2/3 of adult size.

Otherwise, a fairly quiet week bird-wise.

Cackling Goose
Canada Goose
Eurasian Wigeon
American Wigeon
Mallard
Northern Shoveler
Northern Pintail
Green-winged Teal
Ring-necked Duck
Lesser Scaup
Bufflehead
Common Merganser
Ruddy Duck
Ring-necked Pheasant
Double-crested Cormorant
Great Blue Heron
Great Egret
Turkey Vulture
Bald Eagle
Northern Harrier
Red-tailed Hawk
Peregrine Falcon
Killdeer
Greater Yellowlegs
Mourning Dove
Great Horned Owl
Anna's Hummingbird
Rufous Hummingbird
Belted Kingfisher
Downy Woodpecker
Northern Flicker
Steller's Jay
Western Scrub-Jay
American Crow
Tree Swallow
Black-capped Chickadee
Bushtit
White-breasted Nuthatch
Bewick's Wren
Marsh Wren
Ruby-crowned Kinglet
American Robin
European Starling
Yellow-rumped Warbler
Townsend's Warbler
Common Yellowthroat
Spotted Towhee
Savannah Sparrow
Fox Sparrow
Song Sparrow
Lincoln's Sparrow
Golden-crowned Sparrow
Dark-eyed Junco
Red-winged Blackbird
House Finch
Pine Siskin
Lesser Goldfinch
American Goldfinch

Bewick's Wren, an early spring singer

Bewick's Wren, Jackson Bottom Wetlands, Hillsboro, Oregon on 4 March 2010 by Greg Gillson.

 

Throughout its range across North America, the Bewick's Wren (previous article) shows much plumage and song variation.

In addition, populations in Eastern North America are declining, while many populations in Western North America are expanding.

The 1979 book, The Birds of Canada by Earl Godfrey, shows Bewick's Wrens in extreme southern Ontario and extreme southwestern British Columbia. This species disappeared from Ontario in the 1970's and, in fact, retracted its range about 700 miles in the East. By the year 2000, according to the map in The National Geographic's Complete Birds of North America (2006) edited by Jonathan Alderfer, the wren perhaps now breeds no closer than southwestern Kentucky.

In contrast, the Bewick's Wrens in the Pacific Northwest are expanding their range inland along the Columbia River. Historically, they were common along the Columbia River only west of the Cascades, with a small isolated population near Yakima, Washington. In the last 30-40 years, though, they have expanded upriver until they are regular to the Walla Walla River and other areas surrounding the corner where Washington, Idaho, and Oregon meet.

The photo above shows a typical example of the population called the Seattle Wren (Thryomanes bewicki calophonus). This is the form found from SW BC, western Washington and Oregon (from Cascades to coast) south to Roseburg and Coos Bay, Oregon. [It is also likely the form expanding up the Columbia River to the east, but this has not been proved definitively.] It is browner and darker than most other forms in the West, slightly more reddish on the flanks and larger, with longer bill, tarsus, and middle toe.

The subspecies name, calophonus, means a beautiful singer. This bird does, indeed, have a variety of songs. Most take the form of Song Sparrow, with a few introductory chip notes and a trill. But there is much variation. These birds are one of the first singers of spring, singing away in March or, indeed, even the odd sunny day in mid-winter. They sing throughout the day, and throughout the remainder of the year to late fall.

For more information on this wren, including the calophonus subspecies of the Pacific Northwest, see the Bewick's Wren account in Bent's Life Histories of North American Birds.

At the pond... Hooded Merganser

Hooded Merganser, Hillsboro, Oregon on 16 February 2009 by Greg Gillson.

 

What is it that makes the Hooded Merganser such a desirable bird to see? Why is it on everyone's list of favorite ducks?

Well, certainly, birds with crests seem to be favorites (think cardinal, pileated woodpecker, and cedar waxwing). As crests go, the Hooded Merganser's flamboyant fan-like headdress is pretty impressive!

But this striking beauty rarely parades around in the middle of the pond showing off with all the other ducks. Instead, like searching for hid treasure, this secretive inhabitant of backwaters and wooded pond edges usually takes a bit of effort to find.

Hooded Mergansers breed along forested ponds and streams across the mid-latitudes of North America, wintering coastally and southward where water remains open in winter.

In the Pacific NW, they breed in wooded wetlands, most commonly west of the Cascades. They also breed at scattered locations east of the Cascades, such as in NE Oregon, across northern Washington and southern British Columbia, to northern Idaho. They winter throughout the region on open water, though most commonly on freshwater ponds and quiet rivers west of the Cascade crest.

They nest in old flicker holes and will nest in artifical nest boxes designed for Wood Ducks. The chicks are precocious and leave the nest cavity for protected waters the next day after hatching.

They dive for fish, aquatic insects, and crustaceans.