Rapid borealization of Arctic marine fish communities
Dr André Frainer1, Raul Primicerio2, Michaela Aschan2, Maria Fossheim3, Andrey Dolgov4
1Norwegian Institute for Nature Research (NINA), Tromsø, Norway, 2UiT The Arctic University of Norway, Tromsø, Norway, 3Institute of Marine Research (IMR), Tromsø, Norway, 4Knipovich Polar Research Institute of Marine Fisheries and Oceanography (PINRO), Murmansk, Russia
Climate change affects species distribution, with observed rapid effects on the functional composition of Arctic marine fish and several other marine species across the globe. Using data from an extensive survey conducted over 400 stations across 14 years, and covering the entire Barents Sea, we show that marine fish Arctic communities are under a process of rapid borealization. First, community-based mean values indicate that boreal functional traits are increasingly becoming dominant in Arctic stations. Then, assessing community-level variance, we show that the Arctic region as a whole already possesses the traits that makes it resemble the boreal region. This is followed by an increased functional diversity in the region led mostly by the addition of traits related to predator and superior competitor species. The increase in functional diversity in the Arctic has clear consequences to its ecosystem functioning, including energy flow patterns and biomass accrual. This result is alarming and indicative of a change at an unprecedented rate. Assessments of species and functional composition are key to lay the foundation for sustainable economic policies, to adjust current harvesting practices, and to conserve areas of special interest. Thus, early warning signals of functional change as shown here are paramount for rapid and effective policy adaptation in light
Biography:
PhD in Ecology (2014), works on disentangling how biodiversity is affected by the environment and how it affects ecosystem functioning.