Early morning on the 16th of August 2013 the German research vessel Heincke leaves the port of Bremerhaven. On board are a handful of fish nets, two dozens empty aquariums and seven scientists on a mission: to fill the vacant fish tanks with hundreds of juvenile Atlantic and Polar cod. For this purpose they head north, pass by the port of Tromsø in Norway, and continue further to their destination: Spitsbergen.
Here they want to investigate the distribution of the two fish species. And they already have a suspicion: Due to warming water temperatures the Atlantic cod ventures farther and farther north and is now settling in the Arctic waters of the archipelago – where it encounters the region’s key species, the Polar cod. In case it comes to a rivalry between the species, the scientists assume that the highly adaptable Atlantic cod might hold the ground.
The scientists are, however, venturing to Svalbard for a further reason: They want to bring back Atlantic cod and Polar cod alive to Bremerhaven in order to investigate how these fish react to ocean acidification. Because human induced emissions do not only heat up the atmosphere. Carbon dioxide also diffuses into the oceans and slowly makes them more acidic. And the Arctic presents the perfect research conditions. As cold waters absorb more carbon dioxide, the high latitudes will be the first ones affected by the so-called ocean acidification.