Age, growth and productivity of juvenile sockeye salmon in two high latitude lakes, Alaska

Abstract

"The growth of Seward Peninsula sockeye salmon (Oncorhynchus nerka) from Salmon and Glacial lakes is related to their physical environment. Dermal scales collected over many years were measured to document the annual age specific growth of smolts and adults. The effect of fertilization on fry growth was examined using the first year of growth. The growth histories of Salmon Lake sockeye salmon were compared to Glacial Lake sockeye salmon through smolting and in the marine environment. Annual age specific fry growth had no direct relationship to fertilization; however, there were interactions between biomass of salmon prey and fertilization, and between prey biomass and age of smolting. Glacial Lake age-1 smolts are the same size as Salmon Lake age-1 smolts, but age-1.3 Salmon Lake juveniles after their first year in the ocean are smaller than age-1.3 Glacial Lake juveniles suggesting lower size based mortality. The differences in growth histories show each population's response to lake production and mortality experienced by smolt between the rearing lake and the ocean"--Leaf iii