Pacific Lamprey

The Pacific lamprey (Entosphenus tridentatus) is an anadromous species that is native to the Pacific Rim and migrates from the ocean to freshwater to spawn. This species lives from 7 to 11 years, spending its larval stage in rivers and migrating to the ocean during its juvenile and adult life phases. Pacific lamprey have an eel-like body and will reach 1.5 to 2.5 feet in length as adults. Like other lamprey species, they have a round mouth and lack scales and gills. Juveniles of this species are brown in color but change to silver when they age into adults. In their adult stage, this species is parasitic and feeds on a variety of marine fishes. During spawning, both males and females construct nests. Populations of this species have declined in recent years due to habitat degradation, among other factors.

Fun Fact: Pacific lamprey will not eat once they return to rivers for spawning. This can result in them losing up to a third of their length!