ANALYSIS OF THE SPRING-FALL EPIPELAGIC ICHTHYOPLANKTON COMMUNITY IN THE NORTHERN CALIFORNIA CURRENT IN 2004-2009 AND ITS RELATION TO ENVIRONMENTAL FACTORS

The taxonomic composition, distribution, concentration, and community structure of ichthyoplankton off the Oregon and Washington coasts were examined in 2004-2009 to investigate annual, seasonal, latitudinal, and cross-shelf variability. Larval concentrations and community structure were also analyzed in relation to several local and larger-scale environmental variables. The dominant taxa, comprising 94% of the total larvae collected, were Engraulis mordax, Sebastes spp., Stenobrachius leucopsarus, Tarletonbeania crenularis, and Lyopsetta exilis. Larval concentrations and diversity generally varied across the temporal and spatial scales. Several seasonal and cross-shelf assemblages were identified, and annual, seasonal, latitudinal, and cross-shelf gradients of taxonomic associations with significant indicator taxa were found. 'Distance from shore, salinity, and temperature were the local environmental factors that explained the most variability in larval fish concentrations, while Columbia River outflow and sea-surface temperature were the larger-scale factors that explained the most variability in 2-4 month lagged larval fish concentrations and diversity.