ARK
Arctic marine mammals in a time of climate change: a Kongsfjorden Case Study (ARK)
Declines in sea ice (volume, extent, seasonal coverage) and melting and retraction of tidewater glaciers in the Arctic are particularly visible signs of change that is occurring due to global warming. Degradation of both of these physical features of Arctic marine systems are happening more rapidly in the northern Barents Sea than elsewhere in the circumpolar Arctic making the Norwegian High Arctic is a bellwether of climate change for the entire region. The shrinking of sympagic habitats and concomitant Atlantification of Arctic food webs, will undoubtedly have profound implications for marine ecosystems in the High North; the expected implications for endemic Arctic marine mammal species have been described as “transformative”. The ARK research programme will use a variety of “captured” and extended data time series (abundance, ecology, diet, contaminant levels, disease/health, trophic interactions etc) to quantitatively test four principle hypotheses regarding how marine mammals (especially resident endemic Arctic seals but also other species) are being impacted by global warming: 1) H1 – Declining ice habitats will induce abundance declines in ice-dependent species and result in redistributions, and over longer time frames extirpations; 2) H1 – Arctic endemic species will face increasing competition from temperate species that are expanding their ranges; 3) H1 – the health of Arctic endemic species will be negatively impacted by increasing exposure to diseases and increased impacts of contaminants and 4) H1 – Atlantification of food webs will affect Arctic marine mammals negatively, creating risks of cascading impacts through Arctic ecosystems. ARK will take a case-study approach, using Kongsfjorden on the west coast of the Svalbard Archipelago to explore ecosystems change, employing state-of-the-art physical-biogeochemical food web models and complex adaptive