Project: PELAGIC

Coastal waters are some of the most productive marine ecosystems. With climate change, coastal waters are becoming warmer and darker, and the ecological consequences are unclear. In the PELAGIC project, we will study how the feeding grounds of pelagic fish (herring, sprat, mackerel, etc.) may change as a result of these two climate impacts.

Pelagic fish primarily use their vision to hunt for food, and the size and visibility of prey (zooplankton) may be more important than the actual amount of prey for effective food intake. Both warming and darkening are expected to affect the size structure of plankton communities, which have short life cycles and respond quickly to environmental changes. In the project, we will study historical plankton samples using new technology and further develop an ecosystem model to increase understanding of how temperature and light conditions affect the size of plankton communities along the Norwegian coast – both historically and in a future perspective. If fish become less able to utilize their feeding grounds, this could give an advantage to gelatinous plankton (jellyfish) that do not depend on light and plankton size to hunt for food. Therefore, we will also look more closely at the competitive relationship between fish and gelatinous plankton in selected fjords and the potential for a regime shift towards more jellyfish and less fish in the future.