Pacific lamprey in the Owyhee
Yesterday’s Oregonian carried a front-page story on the annual harvest of Pacific lamprey at Willamette Falls by Columbia river tribal members. As many readers will know, the lamprey is an anadromous species that for millions of years (the article says 360 million) has migrated up the Columbia and its tributaries and has been used by Columbia Basin tribes for ritual purposes as well as a food source. Like the salmon, the lamprey’s fate in the last century or more is a cautionary tale in the unintended consequences of man’s efforts to “improve” on nature. The Owyhee serves as an excellent example.
When European Americans began settling the Owyhee canyonlands in the mid 19th century, the annual migrations of Pacific lamprey and salmon were rich. One estimate puts the annual take of salmon by tribes in southeastern Oregon and northern Nevada at around 90,000 fish. I’ve seen no estimates for the lamprey, which is perhaps a reflection of non-Native American attitudes toward the species; it is a parasite and their round sucker-like mouth with rows of sharp teeth used to attach to fish makes them unattractive.
The Owyhee settlers’ first impact on the Pacific lamprey came when they constructed enormous waterwheels–in one case reaching as high as sixty feet–to lift water from the river to their fields and pastures. Diversion dams were built to direct the water’s flow to fill the waterwheel buckets. Lampreys carried along with the flow were willy-nilly picked up by the waterwheels and dumped into the irrigation ditches that carried them into fields where they died. As one resident described the phenomenon, “When we irrigated in the spring, the eels used to come up that river and I’ve seen them so thick in the field after they come up the flume that you couldn’t hardly get out into the field because of them old dead eels. The water wheel picked up them things because they had to go through the wheel when the came through the river. They couldn’t get through the dam. The buckets picked up a lot of them.”
Most of the waterwheels disappeared when the Owyhee dam was built and the reservoir flooded farms north of Watson that had relied on them. A remnant can be seen at the Birch Creek ranch south of the end of the reservoir. The dam presented an even greater threat to the lamprey as well as to the salmon. The highest arch-gravity arc in the world when it was completed in 1932, unlike dams on the Columbia and later on the Snake, the Owyhee dam made no provision for the migrating salmon. (I doubt it occurred to the builders dams to make provision for the lamprey.) The result was predictable: the Pacific lamprey disappeared from the Owyhee watershed. So did the salmon. And so did an important source of aquatic nutrients for the watershed and, sadly, a characteristic element in the way of life of the original inhabitants of the region.