Pacific Lamprey Attemping Van Arsdale Fish Ladder

During a site visit to the Potter Valley Project Friends of the Eel River staff observed lamprey attempting and mostly failing to climb the fish ladder at the Van Arsdale fish counting station.

Pacific Lamprey, the fish for which the Eel River was “mis-named” are anadromous just like salmon, meaning they migrate between freshwater and saltwater. Dams block lamprey access to upper watershed habitat in much the same way they do for salmon. Fish ladders designed for salmon don’t work well for lamprey who use their sucker mouths to grip onto flat surfaces and move upstream. At Van Arsadale Fish Station, located at Cape Horn dam (the first of the two Eel River dams), biologist have gotten creative with helping lamprey over the dam. Read about their solutions for lamprey passage here.