Nearshore macrobenthos of northern Kotzebue Sound, Alaska, with reference to local sewage disposal

Abstract

Macrobenthos of the shallow (\10 m) near- shore marine waters of northern Kotzebue Sound was examined in 2002-2004 to (1) determine nearshore com- munity structure and (2) assess the influence of sewage disposal. A variable number of benthic stations were sampled during three summers, with extensive effort at the disposal zone in 2003. The benthic community structure is similar to other nearshore Arctic locations, and was similar to a previous benthic study done in 1986-1987. The potential of sewage impact was assessed at the request of the community, because sewage is occasionally discharged into the Sound, in volumes of up to 38 million liters, typ- ically through the ice in early spring. Only minimal effects of disposal on the benthos were evident and the effects could not be separated from the impacts of low salinity and relatively high water pigments. Low diversity (H 0 ) and species richness (d) and high biomass characterized sta- tions in the sewage area. Parameters often associated with extreme sewage pollution, particularly hypoxic and/or anoxic conditions and high abundance of opportunistic taxa, were not observed. Local traditional ecological knowledge was solicited throughout the study, and was used to help define the area potentially affected by sewage disposal.