Catch the drift for Willamette River birding.

Byline: Dan Gleason For The Register-Guard

The Willamette River offers opportunities for many kinds of recreation, including birding. Some birds are found over or on the river, and a few are even found under the water as they search for food.

Most birds frequent riparian vegetation along the river's margins. Birds found near streams, such as yellow warblers, also are found in habitats away from streams. Yet a few birds, like the American dipper, can be found only in association with water.

As the snow retreats and the breeding season peaks, portions of the Willamette River at higher elevations become more accessible. One favorite spot for travelers along Highway 58 is Salt Creek Falls. At 286 feet in height, this is the second-highest waterfall in Oregon.

In the stream at the top of the falls, you are very likely to see an American dipper, continually bobbing up and down while standing on a streamside rock. Suddenly it will launch itself into the river, using its wings to "fly" underwater, where it feeds on caddis flies and other aquatic insects.

Nearby, high in the conifers, you are likely to hear the clear, flute-like notes of the hermit thrush. Although these birds nest on or near the ground, the males sing their beautiful song from a high perch in the forest. Listen carefully, because the bird is actually singing two notes simultaneously. The syrinx (the unique vocal apparatus of birds) is divided into two portions. One side sings the low notes while the other simultaneously sings a completely different song at a higher pitch.

Thrushes, especially, are noted for this double-vocal ability. Another you might hear in riparian zones is the Swainson's thrush, found in the low trees and brushy vegetation near the river. Their clear notes spiral upward in pitch.

A long, buzzy whistle in a single pitch means you have heard a varied thrush. After a pause of only a second or two, it will sing its haunting whistle again, this time on a different pitch. If you finally see this songster, it looks similar in color to an American robin, but it's distinguished by a black V across the breast and an orange line above the eye as well as more subtle differences.

For birders, the lure of Salt Creek Falls is the black swift. This bird nests in crevices on Western mountain cliffs, especially near waterfalls. What makes Salt Creek Falls unique is that it's the only place in Oregon where this bird can be found. Many places around the state look as if they would be good black swift habitat, but no nests have been found except here. Nests are tucked in a crevice near the top of the falls and are extremely difficult to locate, but watch for the birds flying overhead near the falls.

Black swifts are a bit larger than the more common Vaux's swift you may be familiar with in the valley, but Vaux's swifts also are common over forests, so pay careful attention to avoid confusing the two species.

Downriver diversity

American dippers prefer mountain streams. But as you move into the foothills, you encounter a variety of river habitats, and with them a great diversity of birds. Elijah Bristow State Park near Dexter is a good stopping point for birdwatching. This park offers many habitats, including grasslands, deciduous and mixed woodlands, and coniferous forests.

Listen for a bright, forceful, high-pitched song in willow thickets along the river. If you find him, the singer is a small, bright yellow bird - a male yellow warbler - feeding as he flits from branch to branch.

Common in willow and deciduous thickets near water during the breeding season, the female is dull yellow. But the male is bright yellow with pale-orange streaks on his breast. His song brings a cheerful moment to a summer's day.

Swallows are busy in their aerial pursuit of insects just above the river's surface. Tree swallows, violet-green swallows and Northern rough-winged swallows are all found along the river as it passes Elijah Bristow park.

Flying back and forth across the river, but higher than most swallows, you may see cedar waxwings catching flying insects. They have a soft, rosy-tan plumage, a crest on the head and a black mask over their eyes, making them a bird of subtle beauty. But these details can be difficult to see when the birds are in flight, so look for a bright-yellow band at the tip of the tail.

If loud chirping draws your attention high overhead, look for an osprey wheeling over the river, calling loudly while it looks down, studying the water for an easy-to-catch fish. If it spots one, watch it dive head-first toward the water, throw its feet forward at the last moment, and extend its talons to capture the fish swimming near the surface. When the osprey emerges from the river, watch closely, for if it has been successful, it will turn the fish to face head-first into the wind to offer less wind-resistance, making flight easier.

Like Salt Creek Falls, Elijah Bristow park also harbors a rare sighting for birders.

The red-eyed vireo is a bird more common to Eastern deciduous forests, and while uncommon in the West, Elijah Bristow is one of the few places where it is often found.

Dull-colored plumages and slow movements from tree to tree make vireos easy to overlook. They are best located by voice, so study one of the many recordings available or attend a field trip with a local expert if you are not familiar with these interesting birds.

The diversity of species along the Willamette River is much too great to enumerate here, and I can only provide a few brief examples.

But, the next time you have the opportunity to explore sites along the river, listen for the variety of bird songs you hear and take time to locate and watch the birds near you. You will find many beautiful birds along the river, and perhaps you will find a new bird to add to your Oregon bird list.

BIRDING BOOKS

For more on local birding, consider two books:

"Birds! From the Inside Out" by Dan Gleason. Inquire at the Tsunami and Borders bookstores in Eugene, or order from the author at [phone] or e-mail at [e-mail]. Gleason is a retired University of Oregon biologist who teaches field ornithology at the university and community classes on birds and natural history.

"Birds of Lane County, Oregon" by Alan L. Contreras, ed. Published by OSU press; available in bookstores that carry nature-oriented books.