Intertidal ecosystem response to an increasingly ice-free Arctic

Warming temperatures and a reduction of sea-ice scour opens the Arctic intertidal as habitat for colonization by both seaweeds and marine invertebrates. Indeed, large increases in the biomass of seaweeds and invertebrates on Arctic coasts have already been documented in the past decades and are predicted to continue. To understand the ramifications of this widespread ecological change in the Arctic intertidal, one needs to examine species-specific responses and how these drive inter-species interactions and ecosystem dynamics. Information about Arctic intertidal communities across environmental gradients are few, and even more scarce are studies on: species adaptability, biotic interactions, and regional variability in population and community structure, all of which contribute to ecosystem stability. We propose to examine the stability of components of the Arctic intertidal ecosystem along an environmental gradient (low wave & sea-ice stress -> high wave & sea-ice stress). Specific objectives are to study the effects of abiotic forcing on i) seaweed morphology ii) the colonization of the intertidal by seaweeds and invertebrates iii) the genetic constitution of intertidal seaweed and invertebrate populations. During a field expedition to Svalbard in the summer of 2024, we will perform quadrat and transect surveys of intertidal biota, as well as collect samples for further morphological, taxonomical, and genetic analyses. The main challenge is to collect samples at sites that present a broad enough environmental gradient for an impactful study. We can reach a variety of exposed and sheltered sites in Kongsfjorden to achieve the stated objectives. Collaboration with other researchers to obtain freshly collected or preserved material for genetic analysis from Svalbard outside of Kongsfjorden will be desirable to broaden the scientific impact of this study.