Felix Mark, marine ecophysiologist at Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), investigates the effects of climate change on two closely-related fish species in the Arctic. Due to rising water temperatures, the Atlantic cod is moving northwards and might take over the habitat of the native polar cod.
Laboratory experiments at Alfred Wegener Institute in Bremerhaven have shown that the highly specialised polar cod needs certain temperatures to thrive. The Atlantic cod is far more able to adapt to changes in its environment. This might mean that stocks of Atlantic cod increase. But in the long run, it is unclear if the Arctic ecosystem supports large populations of this voracious predator.