South Fork of the John Day River
The various forks of the John Day River and many of its tributaries originate high in the Blue Mountains. The South Fork of the John Day River flows west through its valley, passing ranches, farms, and communities before turning north as it enters John Day Fossil Beds National Monument. After passing through Picture Gorge, tt is joined by Rock Creek the next 8 miles flow through the Sheep Rock Unit of the monument.
Scattered cottonwoods, willow, and alder provide shade and leaf matter for the nutrient cycles of the river. Sedges grow along the gravel bars and up the banks, with many grasses and shrub willow providing herbaceous cover, protecting the river banks.
Elk, deer and coyotes can be seen coming down from the hills to drink at the waters edge. Evidence of beaver and mink can be found along with occasional sightings of river otters, which were reintroduced to the river by the Oregon Department of Fish and Wildlife. Choruses of frogs can be heard on a warm evening while bats swoop down to catch insects and to get a drink on the run.
Neotropical birds, swallows, geese and chukar nest along the shores and use the water as they rear their young. Bald eagles can be seen hunting for fish along the river corridor during the winter, while great blue heron, osprey and kingfishers feed from its water year-round.
Various aquatic insects and hatches of mayflies and their relatives are seen during the summer. As the snows melt in the mountains above, young salmon and steelhead smolts swim through on their way to the ocean, while adults work their way up the river to spawning beds.
Runoff and snowmelt from the Painted Hills Unit drain into Bridge Creek, which flows along the eastern boundary of the unit. Though small, the perennial flow of the stream provides water to wildlife throughout the year. Russian olive have gained a foothold along the banks, but the monument is making a strong effort to remove these "invaders" and replace them with native cottonwoods and willows. Bridge Creek heads off to the northwest as it leaves the park and flows several miles before entering the John Day River.
The canyons and intermittent streams of the Clarno Unit flow southward into Pine Creek, just south of the unit boundary. Indian Canyon can occasionally carry some heavy flows of water. The lower portion of the John Day River, just a short drive from Clarno, is famous for its rafting and smallmouth bass fishing.