WETLANDS AND RIPARIAN

Wetlands and Riparian

Wetlands

Wetlands are nature's reservoirs and water filters. They absorb and store water, help control stream flow and thus provide natural flood control. Wetlands are among Oregon's most biologically productive, species-rich habitats, and are especially important for nurturing aquatic and terrestrial plants, animals, fish and insects. These wetlands also provide vital habitat for imperiled species like winter steelhead, spotted frogs and western pond turtles. They also support migrating birds like sandhill cranes, tundra swans, dusky Canada geese (which winter only in the Willamette Basin), bald eagles, herons and many species of ducks and shorebirds.

For much of this country's history, wetlands have been misunderstood. Often maligned as bogs, marshes and swamps, wetlands were thought to be unhealthy places of no practical use. In the Willamette Basin, settlers drained wetlands to grow crops, accommodate livestock grazing and for residential and commercial development. About half of the Basin's wetlands are now gone (estimates range from 41 to 87 percent). Recently, remaining wetlands have been converted to other uses at a rate of over 500 acres a year. Consequently, many of Oregon's native wetland plant communities are imperiled, as are many of the state's wetland-dependent amphibians.

Riparian Habitats and Bottomland Forests

Before the Willamette Basin was thoroughly settled and developed, dense forests lined the Willamette River and its tributaries. These diverse forests—some dominated by conifers, others by hardwoods—were one to seven miles wide. Today over 80 percent of these riparian, floodplain, bottomland and gallery forests are gone, most converted to agriculture and commercial and residential development. A few, protected in parks, are wider and offer a glimpse of these forests' amazing richness.

Douglas fir, western hemlock, Pacific yew, black cottonwood, red alder, big leaf and vine maple, western red cedar, Oregon ash, willow and pine all grow here. Several types of ferns uncurl from the forest floor. In the cool damp earth violets, trillium, orchids, bleeding heart, oxalis, bunchberry and calypso orchids bloom. Pileated woodpeckers work the tree trunks, and dippers duck for insects in nearby streams. Salamanders and frogs make their home in the moist streambank soil. A reliable place to see calypso orchids is near the visitors' center at Silver Falls State Park, where they grow in an area fenced to protect the rare plants. The orchids bloom in April and are very small, so look closely.

Among the birds found in Basin bottomland and riparian forests are red-eyed vireo, yellow warbler, yellow-breasted chat, olive-sided flycatcher, warbling vireo, Bullock's oriole, robin, willow flycatcher and dipper. Look for downy woodpeckers, black-capped chickadees and tree swallows hunting insects on tree trunks and snags. Around flowering and berry-producing plants and shrubs, look for cedar waxwings, Swainson's thrushes and rufous hummingbirds. The yellow-billed cuckoo lived in Willamette Basin riparian forests but has not been seen here since about 1977; confirmed breeding pairs have not been seen in Oregon since the 1940s.

Additional Resources

A Place for Nature