FEASIBILITY OF USING LANDLOCKED ATLANTIC SALMON (SALMO SALAR) FOR MARINE CULTURE.

A MAJOR PROBLEM IN MARINE CULTURE OF ATLANTIC SALMON (SALMO SALAR) IN THE NORTH-EASTERN UNITED STATES IS THE LACKOF EGGS AND SMOLTS. DIADROMOUS (SEA-RUN) ATLANTIC SALMON EGGS ARE SCARCE AND NEEDED FOR RESTORATION PURPOSES. ALSO, YOUNG SEA-RUN SALMON ARE DIFFICULT TO REAR THROUGH THE PRE-SMOLT STAGE. MAINE HAS NATIVE POPULATIONS OF LANDLOCKED ATLANTIC SALMON (S. SALAR) THAT MIGHT SERVE AS ANALTERNATE TO SEA-RUN STOCKS FOR MARINE CULTURE. RESEARCH OBJECTIVES ARE: (1) TO COMPARE GROWTH AND MORTALITYOF PRE-SMOLT, LANDLOCKED, AND SEA-RUN ATLANTIC SALMON REARED UNDER ACCELERATED CONDITIONS; (2) TO DETERMINE THE SMOLT STATUS OF ONE-YEAR LANDLOCKED ATLANTIC SALMON BASED ON PHYSIOLOGICAL AND PHYSICAL TESTS; AND (3) TO COMPARE GROWTH AND MATURITY CHARACCTERISTICS OF POST-SMOLT LANDLOCKED AND SEA-RUN SALMON IN SEWATER CAGES. TO ACCOMPLISH THESE OBJECTIVES, WE WILL USE COMPARATIVE REARING TRIALS IN FRESHWATER AND SEAWATER; AND TESTS OF SMOLTIFICATION INCLUDING GILL NA+-K+ ATPASE, PLASMA THYROXINE AND OSMOLARITY, SALINITY TOLERANCE, AND PHYSICAL AND BEHAVIORAL CRITERIA. THIS RESEARCH WOULD CONTRIBUTE BASIC AND APPLIED KNOWLEDGE ON THE PHYSIOLOGY, ENDOCRINOLOGY AND BEHAVIOR OF THE LANDLOCKED ATLANTIC SALMON, ESPECIALLY SMOLTIFICATION. RESULTS COULD BE APPLIED TO INCREASE THE SUPPLY OF SEEDSTOCKNEEDED BY U.S. SALMON GROWERS, AND THUS REDUCE RELIANCE ON IMPORTED SALMON.