ARCUS | Arctic Research Consortium of the United States

6th Annual ARCUS Award for Arctic Research Excellence


Submitted by   Katrine Borgå
Authors   Katrine Borgå, G.W. Gabrielsen, and J.U. Skaare
Category   Life Science
Title   Differences in contamination load between planktonic and ice-associated fauna in the Arctic marginal ice zone: influence of habitat, diet and geography
Affiliation   Department of Aquatic Resources and Environmental , University of Tromsø, Tromsø, Norway

Abstract

Concentration and transport of organic pollutants by Arctic sea ice may expose ice-associated fauna to high contaminant concentrations relative to pelagic organisms. Zooplankton and ice-associated amphipods were collected in the marginal ice zone near Svalbard to investigate if habitat, diet and geographic sampling site influenced their organochlorine burden. Organochlorine concentrations were low in both zooplankton (Calanus hyperboreus, Thysanoessa inermis, Parathemisto libellula, Chaetognatha) and ice-associated amphipods (Apherusa glacialis, Gammarus wilkitzkii, Onisimus spp.), from 0.3 ng·g-1 lipid weight transchlordane in A. glacialis to 36.9 ng·g-1 lipid weight hexachlorobenzene (HCB) in G. wilkitzkii. Diet accounted for most of the organochlorine variance explained, followed by habitat and geographic sampling site. The concentrations were higher in carnivores (P. libellula, Chaetognatha, G. wilkitzkii, Onisimus spp.) than in herbivores (C. hyperboreus, T. inermis, A. glacialis), The HCB, y- and x-hexachlorocyclohexane (HCH) concentrations were higher in ice-associated amphipods than in zooplankton, whereas the other compounds did not differ significantly between habitats. HCHs were the only compounds that differed geographically. Higher x-/y-HCH values in C. hyperboreus and A. glacialis from the Greenland Sea relative to North of Svalbard, are consistent with the geographic patterns in HCH levels reported for air, water, ice-associated amphipods and ringed seals (Phoca hispida).