Thank you to Marty Liedtke and Lisa Weiland for submitting this photo taken by Joe Skalicky at the U.S. Fish and Wildlife Service to our newsletter's photo contest. In this photo, WFRC scientists Lisa Weiland and USFWS hydrologist Leah Tai dig in the mud to understand how larval lampreys use soft substrates for burrowing. Pacific lamprey, Entosphenus tridentatus, are among the oldest fish species in the world, appearing in fossil records as old as 450 million years. These eel-like fish have a fascinating life cycle and spend the majority of their lives as larvae, called ammocoetes. Ammocoetes live burrowed in in soft bottom substrates for 3-7 years, filter feeding on organic matter as water passes by. After they emerge, they metamorphosize into a more-recognizable lamprey shape before migrating to the ocean, where they parasitize fish and mammals. As adults, lampreys return to streams to spawn. 

In partnership with scientists at USFWS, Marty Liedtke and Lisa Weiland seek to understand how larval lamprey populations survive under various substrate conditions. In this photo, Leah Tai (USFWS, standing on the right) and Lisa Weiland (WFRC, left) use a modified clam gun to sample sediment and the ammocoetes within it, analyzing water quality in the substrate and characterizing the type of sediment the fish are burrowed in.