Environmental Influences on Landlocked Fall Chinook Salmon Reproductive Characteristics

Abstract

Abstract From 1988 to 1998, we evaluated relationships among several environmental and biological variables and the fecundity, egg size, and embryo survival to the eyed stage of landlocked fall chinook salmon Oncorhynchus tshawytscha from Lake Oahe, South Dakota. The environmental variables recorded in Lake Oahe included monthly and total yearly inflows and outflows, end-of-month elevations, yearly mean end-of-month elevations, and 13°C and 15°C habitat volumes. Biological variables included gill-net catch per unit effort (CPUE) of lake herring Coregonus artedi, rainbow smelt Osmerus mordax, and chinook salmon (for age-0, age-1 and older, and all fish); chinook salmon age-1 mean relative weight; and rainbow smelt abundance in both the 13°C and 15°C habitat volumes. Chinook salmon fecundity was significantly related to rainbow smelt CPUE (r = 0.841) and chinook salmon CPUE (r = 0.853). Fecundity was also significantly related to mean relative weight of age-1 and older salmon collected in gill nets the year...