Lipid accumulation and (long) periods of diapause are the key traits ensuring successful life history strategy of polar copepods. The lipids have several functions, where the most obvious function is to supply the animal with sufficient energy for survival during overwintering and to fuel gonad development and even egg production. However, lipids are also essential as a buoyancy regulator allowing the copepod to stay torpid at great depths for a long period in a state of diapause. The type of lipids copepods accumulate before entering diapause are wax esters, and their compressibility (thus buoyancy) is dependent on the saturation level of the wax ester.  We present results from an ongoing analysis on the molecular composition of intact wax esters of the Arctic copepod <em>Calanus hyperboreus</em> from several locations; West and East of Greenland and the Nansen and Amundsen basins in the Arctic Ocean.  The overarching questions we seek to answer is if there is a relationship between wax ester structure and the overwintering habitat at which the copepod parks? We focus on the relationship is between the depth (pressure) of overwintering and the saturation of the wax esters and if there is a relationship between the details in the wax esters and seawater density.  Any change in the physical environment can affect the depth and length of overwintering of the copepods and therefore the survival during diapause. Results from ongoing analyses will be presented.

Primary Presenter: Sigrun Jonasdottir, Technical University of Denmark (sjo@aqua.dtu.dk)

Authors:

Sigrun Huld Jonasdottir, Technical University of Denmark  (sjo@aqua.dtu.dk)

Camilla Svensen, University of Tromsoe  (camilla.svensen@uit.no)

Amaya Albalat, University of Stirling  (amaya.albalat@stir.ac.uk)

Richard Broughton, University of Stirling  (richard.broughton@stir.ac.uk)