Genelal description: Ice cores, samples of nilas and snow samples, under-ice water and a sample of frost flowers were taken in the Amundsen Gulf (Canadian Arctic) onboard the CCGS Amundsen. Methology: We used corer to collect ice cores and frost flowers and we used ice cage to collect nilas. We collected descriptive variables for the snow and frost flowers, ice cores and nilas, and for under ice water. For all samples, we measured pH, salinity and conductivity. Back in our university-based laboratories, we studied elemental composition of samples and we carried out scanning electron microscopy.

Samples were collected at 5 sites ranging in water depth from 100 to 595 m at least once in each season (ice-covered and open-water condition) between March and August 2008 onboard the icebreaker CCGS Amundsen. At each sampling station, an USNEL box corer was deployed for collecting seafloor sediments. From each box core, 5 sub-cores of 11 cm diameter and 20 cm sediment depth were taken for assessing benthic carbon remineralisation in microcosm incubations and 3 additional subcores of 5 cm diameter and 10 cm length were taken for determining sediment properties. Incubations of sediment microcosms were run in a dark, temperature-controlled room (2-4 °C) for 24-48 h. Each sediment microcosm was sieved through a 0.5 mm mesh under running sea water at the end of incubations to determine biomass of macrofaunal communities. The sieve residue was preserved in a buffered 4% seawater-formaldehyde solution and analysed for species composition and abundance under a stereomicroscope in the lab.

Bottom water (20 L per station) was collected at 11 stations in Baffin Bay using the CCGS Amundsen’s rosette system. Water was filtered aboard the vessel into glass microfiber (GF-F) filters for Carbon and Nitrogen stable isotopic composition analysis. These data will be used in combination with data on soft coral stable isotopic composition collected from the same region.

Coral samples were collected in Pond Inlet and Lancaster Sound in Baffin Bay using the CCGS Amundsen’s remotely operated vehicle (ROV). Samples from Agassiz trawl and box-core deployments were also kept as part of this study (11 stations). Samples were collected between 253 and 856 m. Specimens were subsampled aboard and frozen for determination of their carbon and nitrogen stable isotopic composition, as well as for lipids and fatty acids composition, as part of a study focusing on the trophic ecology of cold-water corals. Carbon and Nitrogen stable isotope analysis as well as lipids/fatty acids analysis were performed on tissue samples of soft corals at the Stable Isotopes Laboratory and Lipids Laboratory, Memorial University, respectively.