Abstract:
The distribution, taxonomy, physiology and feeding habits of pelagic amphipods was investigated. Amphipods were collected by plankton tow, baited traps, coring (coring through sea ice) or hand collections (from tide cracks). Approximately 2000 individual amphipods were collected. About 75% of the amphipods collected were preserved in vials of absolute ethanol for DNA studies. The remaining 25%
... were split evenly between 4-5% EM grade gluteraldehyde, 5-6% formalin, and frozen dried for SEM, gut content analysis and isotope analysis respectively.
They will be examined for
1) an investigation of the diet of pelagic amphipods by means of visual microscopic gut content analysis, together with stable isotope analysis of carbon and nitrogen isotopic composition of the amphipod,
2) sequencing of the cytochrome c oxidase I (COXI) gene of each morphologically identified species and
3) a comparison of species composition and their respective diets between pelagic amphipods from Terra Nova Bay, an area covered by sea ice and those found in the open water of the Ross Sea.
The rate of movement of amphipods was determined by experimentally exposing amphipods to increasing water temperature and measuring the distance traveled over 30 seconds at each temperature. The distribution of amphipods under the ice was determined by lowering a plankton net to a depth of 5m below the sea ice, withdrawing it, emptying it and counting the amphipods, 3 times at 4 hour intervals over 24 hours.