Ease of Use: Methods for Pacific Lamprey (Entosphenus tridentata) Egg Incubation

Pacific Lamprey (Entosphenus tridentata) are a cultural and traditional resource for the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). A laboratory at Walla Walla Community College was designed to help optimize egg incubation, rearing success, and early life stage survival for Pacific Lamprey. In 2014, we tested four types of egg incubation chambers:  flow-through Eager upwelling jars, re-circulating Heath racks, and two different re-circulating rack systems using Cambro food pans.  The ease of use of each system varied greatly, and was a factor in survival after hatching.  Eager jars have been an accepted method of rearing eggs in the recent past, and have successfully been used for production at our lab in 2013 and 2014.  However, the difficulty in retrieving larvae from the jars impacted survival to later life stages.  The Heath rack for incubating eggs involved a great deal of setup time, but collection of larvae from this system was more successful than for the Eager jars.  The two systems utilizing Cambro pans were the easiest of the methods to use, and required the least maintenance. In the future, modifications to all four systems will yield greater larval capture success, and potentially improve survival to later rearing stages.