Lamprey (and hagfish) are at the base of fish evolution, collectively the jawless fishes or
Agnatha. Pacific lamprey, like Pacific salmon, are anadromous (grow in salt water, breed in freshwater) and semelparous (breed once and die). The adults when at sea rasp tissue and fluids from the bodies of bony fishes. Other lampreys, like brook lampreys, complete their whole lives in freshwater and are primarily filter-feeders/detritivores. As
@Buzzy and
@Stonedfish pointed out previously Pacific lamprey do have important place in the culture of inlands PNW tribes. I know that the Yakama Nation has a specific
program to rebuild Pacific lamprey populations in the Columbia River.
In the PNW, we do not have true eels (Order
Anguilliformes). This group includes moray eels, conger eels, and freshwater eels (Family
Anguillidae). The anguillid eels are catadromous, the opposite of anadromous. And they are semelparous -> spawn once and die. Members of this family breed in the ocean and migrate as larvae into freshwater rivers. They may spend several years in lakes and rivers before migrating back to the ocean and to the general area where they were born. American eels (
Anguilla rostrata) and European eels (
A. anguilla) have historically been harvested in hoop traps. It is VERY disconcerting to be snorkeling in a freshwater pond in New England and have a 3-4' long eel swim up to you. Both species migrate thousands of miles to spawn in the Sargasso Sea. Both species (but especially the
European eel - considered critically endangered) are in substantial decline due to poor freshwater conditions, barriers to freshwater migration, and overharvesting.
The other "eel-like marine fishes in the PNW are not members of the Anguilliformes. The
wolf eel is in its own family, the
Anarhichadidae, and most closely related to another group of eel-like fishes, the eel pouts (Family
Zoarcidae). The eel-like fishes that you find in tide pools and under rocks in the intertidal are various species in the family Pholidae (gunnels, a family within suborder Zoarcoidei) and the Stichaedae (a family within the order
Perciformes). The ling cod is an eel-like fish related to greenling; it is neither a ling (a type of cod) or a cod. Common names can be a nightmare. [Though, to be honest, the use of molecular phylogenies have led to major disruptions to the scientific names, both genus or species, for lots of marine organisms. But that has the potential to settle down with more accurate understanding of the evolution of diversity on Earth.]
Steve