Seasonal dynamics of sympagic meiofauna in a high-Arctic fjord

Sea ice plays a vital role in the Arctic ecosystem with many organisms of all sizes depending on it as a habitat, feeding, breeding and nursery ground. Brine channels that form through the ejection of salt from the freshwater lattice during the formation of sea ice, offer a unique habitat for specialized microscopic flora and fauna referred to as sympagic (ice-associated). In seasonal first-year ice, sympagic meiofauna originate from the pelagic and benthic realm, and they inhabit the ice to fuel reproduction and growth of their larvae. This project aims to collect sympagic meiofauna sea ice samples in order to conduct growth and feeding experiments with two dominant sympagic organisms from Van Mijenfjorden, Svalbard. This work will be a continuation of the fieldwork that I conducted this year as part of the FAABulous project, where I successfully sampled landfast ice along a depth transect. The samples that have been analysed so far, from spring 2017, are demonstrating distinct differences among stations. Part of the winter-spring transition was captured by the appearance of juvenile nematodes and larger polychaete larvae at the end of April. Little work has been done on the life history and feeding ecology of individual organisms that occupy the sea ice. More in-depth studies of individual sympagic specimens are needed in order to establish their life history and feeding ecology, especially in the light of changing sea ice conditions due to anthropogenic and natural climate change. Sympagic meiofauna samples will be filtered through a 20 um sieve and a sufficient number of target organisms will be picked out of the melted samples for either experiments, which will be run over a one month period.