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Species Spotlight- Pacific Lamprey
 Photo courtesy of Oregon Department of Fish and Wildlife
The Pacific lamprey is a species of eel-like fish. Like salmon, lamprey are born in river systems, spend part of their lives in the ocean, and return to freshwater to spawn. Returning adult lamprey are around 20 to 30 inches long, have a round, suctioning mouth known as an oral disc, and are greenish-brown or bluish-gray in color. Adults can be found ascending the wet rock faces of Willamette Falls, suctioning with their oral discs and flinging themselves upward using their whip-like tails. As long as the spray from the Falls keeps their skin wet, they can survive the climb.
Lamprey, also known as eels, are a vitally important traditional resource for food, medicine, and ceremony for all five of the Tribes on the Portland Harbor Trustee Council. The Tribes harvested lamprey for thousands of years in a number of areas throughout the Pacific Northwest. However, lamprey numbers have declined so dramatically over the last several decades that the only place in the Northwest that still supports a lamprey harvest is Willamette Falls.
Pacific lamprey change a lot in their lifetimes. They start out as eggs, hatching into small, eyeless juveniles called ammocoetes that filter feed in sediments for several years before making their trip out to sea and maturing into macropthalmia. While at sea they feed by parasitism, suctioning onto fish and marine mammals and sucking their blood. On their return trip, lamprey no longer feed but swim, climb, hide, and suction their way to a spawning area, which can take up to a year or possibly longer.
Ammocoetes need river sediments for food and to escape predation. Sediments are plentiful in the Willamette River near the Portland area. Unfortunately, sediments in the Portland Harbor reach of the river also contain toxic contaminants. Few studies exist that measure the lamprey's sensitivity to toxics, but studies conducted by the Portland Harbor Natural Resource Trustee Council using sediments form Portland Harbor suggest that lamprey ammocoetes burrow into contaminated sediment more slowly than into cleaner sediment. Much remains to be learned, but this laboratory behavior could indicate that ammocoetes are more vulnerable to predation in contaminated environments.
On the Willamette River, records of returning adult lamprey numbers were not kept until recently, but historic commercial harvests of thousands of tons of adult lamprey were recorded, making it likely that the individuals numbered in the millions. Today, even with bans on commercial harvests, only a small fraction of their estimated historic population remains. While Pacific lamprey are not currently on the Federal Threatened & Endangered Species list, they are considered a Sensitive Species by the state of Oregon, and several Tribes and government agencies are undertaking major efforts to move the species towards recovery.
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