Comparative studies in biochemical composition of benthic invertebrates (bivalves, ophiuroids) from the Northeast Water (NEW) Polynya

Two species of ophiuroids (Ophiopleura borealis and Ophiacanthabidentata) and bivalves (Astarte crenata and Arctinulagroenlandica) were collected within and adjacent to the Northeast Water Polynya off the northeast coast of Greenland, and analyzed for total moisture, protein, lipid, and ash content. Body composition varied significantly among stations within species. Lipid and protein contents of Astarte crenata were higher in clams collected from the eastern Westwind Trough stations compared to those collected from the western Westwind Trough stations. However, the mean lipid and protein contents were significantly higher in Ophiopleura borealis sampled from the western Westwind Trough compared to the eastern Westwind Trough. Ophiopleura borealis are mobile deposit feeders and scavengers and may not be as directly dependent on sedimentary biogenic material as Astarte crenata and Ophiacanthabidentata. Samples of both Ophiopleura borealis and Ophiacantha bidentata from the Belgica Trough had lower protein and lipid contents compared to those sampled in the western Westwind Trough. Samples of Arctinula groenlandica from two locations on the Ob Bank had significantly different protein levels from each other. These data support previous work, indicating that biogenic materials resulting from primary production in the ice-free western area of the Northeast Water Polynya are advected eastward down the western Westwind Trough and that the Belgica Trough has lower organic input compared to the Westwind Trough. Received: 15 May 1997 / Accepted: 1 October 1997