Description: 15 – 25 inch eel-like species believed to be part of ancient group of fish dating back few hundred million years. Have long brown slender bodies, round sucker-like mouth, no scales and breathe through holes instead of gills. As juveniles develop eyes, teeth and become free-swimming.
Diet: Parasitic/feed primarily on salmon, flatfish, rockfish and pollock. Preyed upon by sharks, sea lions and other marine mammals.
Habitat: Similar to salmon, prefer gravel-bottomed streams, particularly towards upstream end of riffle habitat. Adapted to both fresh and saltwater habitat (anadromous).
Range: Historically found throughout Pacific Rim, from Alaska south to Mexico and along major river systems along Pacific coastline where there were large concentrations of salmon and steelhead. Historically found in robust numbers throughout Columbia, lower Snake, upper Snake and Clearwater Basin. Previously found in Lolo Creek.
Reproduction: Spawning occurs March – July. Both sexes construct nests by moving rocks (gravel) with mouths. Adults die within 36 days of spawning. Ammocoetes (larval lamprey) hatch and drift downstream to areas of low velocity and fine substrates where they burrow, feed on algae and grow for next seven years. Juveniles migrate to ocean, and spend another 1 – 3 years maturing before they cease feeding and migrate back (at night) to freshwater bodies to spawn. Species is thought to overwinter for one year before spawning.
Threats: Dam building frenzy of 20th Century greatly reduced populations; no longer thrives in ecosystems above dams. Culverts, water diversions, tide gates, dredging, poor water quality, changing ocean conditions and predation by non-native fish also depleted populations.
Legal Status: Currently do not receive protection under Endangered Species Act. Listed by Forest Service as Sensitive Species. Columbia River Inter – Tribal Fish Commission has lamprey conservation plan for Columbia River Basin. Learn more.
Miscellaneous: Provided important food source for tribes of Columbia River Basin; prized for rich, oily meat. Generally served alongside salmon during feasts and celebrations. The late Elmer Crow of Nez Perce Tribe fiercely advocated for recovery.