[A-OS13] Marine ecosystems and biogeochemical cycles: theory, observation and modeling

[AOS13-08] Arctic-wide patterns of marine biodiversity under recent climate

*Irene Alabia¹, Jorge Garcia Molinos¹, Takafumi Hirata¹, Franz J. Mueter², Carmen L. David³ (1.Hokkaido University, 2.University of Alaska Fairbanks, 3.Wageningen University and Research)

Keywords:Marine biodiversity, Arctic marine areas, climate change

The Arctic region is experiencing drastic climatic changes bringing about potential ecological surprises. We examined marine biodiversity patterns across eight Arctic marine areas between 2000 and 2019. We compiled species occurrences for 69 marine taxa (i.e., 26 apex predators and 43 mesopredators) and environmental factors to predict taxon-specific distributions using a multi-model ensemble approach. Arctic-wide temporal trends of species richness increased in the last 20 years and highlighted potential emerging biodiversity hotspots due to climate-driven species redistribution. Comparative analyses of species richness and community composition between high and low summer sea ice showed contrasting impacts of and detected areas vulnerable to sea ice changes. In particular, the low summer sea ice generally resulted in species gains (loss) in the Arctic inflow (outflow) shelves, accompanied by substantial changes in community composition. Overall, the recent changes in biodiversity in the Arctic were driven by pervasive poleward range shifts, especially for wide-ranging apex predators. Our findings highlight the varying regional impacts of warming and sea ice loss on Arctic marine communities and provide insights into the vulnerability of Arctic marine areas to climate change.