THE FARMING OF SALMONIDS ACCOUNTS FOR APPROXIMATELY 7% OF THE WORLD'S FISH PRODUCTION AND IMPORTS OF ATLANTIC SALMON WERE VALUED AT MORE THAN 1 BILLION DOLLARS IN 2013, HIGHLIGHTING A TREMENDOUS OPPORTUNITY, AND NEED, FOR DOMESTIC GROWTH. THE COMMERCIAL FARMING OF SALMONIDS HAD ITS INFANCY IN NORWAY IN THE 1960S, AND OPTIMAL CULTURE TECHNIQUES FOR THIS RELATIVELY YOUNG INDUSTRY HAVE YET TO BE DETERMINED. MOST PATHOGENS THREATENING SALMONID PRODUCTION HAVE BEEN SUCCESSFULLY ADDRESSED THROUGH VACCINES OR OTHER MEASURES, HOWEVER, SEA LICE REMAIN THE GREATEST CONSTRAINT TO THE VIABILITY OF THE SALMON FARMING INDUSTRY AND ACCOUNT FOR A NEARLY 300 MILLION DOLLAR LOSS TO THE INDUSTRY ANNUALLY. SEA LICE FEED ON THE FISH'S MUCUS AND SKIN, AND A HEAVY INFESTATION CAN CAUSE CONSIDERABLE LESIONS, WHICH OFTEN LEAD TO MORTALITY. A HEAVY RELIANCE ON PESTICIDES TO TREAT FOR SEA LICE HAS RESULTED IN WIDESPREAD DEVELOPING RESISTANCE TO CURRENTLY AVAILABLE PRODUCTS. THIS PROJECT SEEKS TO IDENTIFY ALTERNATIVE, ENVIRONMENTALLY FRIENDLY COMPOUNDS FOR THE TREATMENT OF SEA LICE, AND WILL IDENTIFY THOSE THAT ELICIT AVERSION BEHAVIOR IN SEA LICE USING A CLASSIC BEHAVIORAL ASSAY. IN ADDITION, WE WILL ASSESS THE EFFECTS OF METHYL FARNESOATE, A KEY INVERTEBRATE HORMONE, ON SEA LICE MORTALITY AND MOLTING FREQUENCY. WE WILL ALSO EXAMINE THE EFFECTS OF THIS COMPOUND ON KEY INDICATORS OF ENDOCRINE HEALTH IN ATLANTIC SALMON. THE INFORMATION GAINED CAN THEN BE USED TO DESIGN FUTURE STUDIES TO DETERMINE SUCCESSFUL ALTERNATIVE APPROACHES FOR THE TREATMENT OF SEA LICE.