U.S. Department of Commerce / NOAA / OAR /  PMEL  / OERD\  \ NMFS / AFSC / RACE/  FOCI

A multidisciplinary research cruise was conducted in the Bering Strait and Chukchi Sea during summer 2004. Ichthyoplankton and juvenile groundfishes were collected at approximately 18 stations in conjunction with CTD data. CTD data were also collected at 57 additional stations. Ichthyoplankton samples contained 23 taxa representing eight families and were dominated by Arctic cod, yellowfin sole, and Bering flounder. Juvenile groundfish collections were comprised of 32 taxa in nine families. Catches were dominated by Arctic staghorn sculpin, shorthorn sculpin, and hamecon. Cluster analysis based on Bray-Curtis similarity coefficients of ichthyoplankton abundance data revealed three distinct species/station groups while four distinct juvenile groundfish species/ station groups were found using presence absence data. BIO-ENV analyses showed temperature most highly correlated with ichthyoplankton species composition and sediment category with juvenile groundfish. Cluster analysis of temperature and salinity data revealed three distinct water masses over the integrated depths of ichthyoplankton tows. However, five water masses were evident in bottom water. Analysis of similarities (ANOSIM) found significant differences in species assemblage structure between water masses for both ichthyoplankton and juvenile groundfishes. Subsequent similarity percentages analyses (SIMPER) determined which species accounted for these differences. We conclude that oceanographic parameters directly influence species assemblages and distributions.