In the United States, the Pacific Northwest encompasses Washington, Oregon and parts of Northern California. This region includes of temperate rainforests, rocky volcanic and sandy coastlines, dry forests and grassland plains. This wide spectrum of habitats plays host to a myriad of bird species from the American crow to the violet-green swallow.
Because many bird species are differentiated by minute details, bring a pair of binoculars or a camera with a suitable lens to get the best look at each bird that you identify. Keep a field guide with you, or bring a sketchbook or notebook and pencil to jot down as many details as you can on each species. Photograph each species or keep track of as many distinguishing characteristics as you can so that you can go back and identify the species more easily later.
Shape and Size
The shape and size of the bird in relation to other birds will help you determine the family and more details about the species. Is the bird small and compact like a hummingbird or large like a crow? Is it aerodynamically built like a swallow or broad-chested like a wren? Identifying the species by its family, such as pigeon, wren, raven, warbler, blackbird, finch or swallow will narrow down the potential species during identification. For example, the black-headed grosbeak and spotted towhee have similar colors and markings, but the grosbeak is larger. The barred owl is a large owl reaching 20 inches in height, while the northern pygmy owl is the smallest Pacific Northwest owl species at a height of only seven inches.
Plumage and Coloration
In the right light, plumage and coloring can tell you a lot about a bird species. Look for distinct markings like spots and bars, interesting colorations and other details that make the species stand out. The ruby-crowned kinglet has a bright red crown on its forehead, while the Wilson's warbler is primarily yellow with a prominent black cap. The yellow-rumped warbler has a yellow cap and a yellow triangle at the base of its tail. The marbled murrelet has distinctive black-and-white plumage.
Feet and Legs
Pay close attention to foot and leg characteristics. Long stalk-like legs generally belong to shore birds and birds that spend time wading through lakes and rivers searching for food like rails, cranes and cormorants. Tiny feet with toes in front and back are best for perching on small branches by the varied thrush, warblers, sparrows and other songbirds. Large, spread-out feet are built for walking and hopping on the ground, and are found on doves and pigeons like the rock and the band-tailed pigeon. Large, powerful feet are for hunting and belong to predatory birds like hawks and eagles.
Beaks and Bills
Another identifying characteristic of bird species is their beak or bill. Beaks and bills are used for many purposes including hunting and catching food, creating nests and cracking nut and seed shells. Long, tubular beaks are probes used by the Rufous hummingbird and other hummingbirds to feed from flowers. Funnel-shaped beaks are exhibited by insectivorous species like the brewer's blackbird and the pine siskin. Shorebirds like ducks use fringed bills to strain food from water and mud. Songbirds like meadowlarks, blackbirds and warblers have long pointed bills that act like tweezers to probe trees and crevices for insects.