Climate change is affecting the vertical migration of zooplankton in the Arctic, with potential implications for the entire Arctic ecosystem, finds a new study, published today in Nature Climate Change.
As the Earth’s climate warms, the extent and thickness of Arctic sea ice are declining; researchers predict that the Arctic Ocean could see its first ice-free summer as early as 2030. As a result, sunlight is reaching deeper into the ocean, affecting the migration patterns of zooplankton – tiny creatures such as krill – which move up and down the water column in response to changing light levels.
The tiny creatures typically prefer twilight conditions and stay below a certain light intensity – known as critical irradiance. As the sunlight changes throughout the day, or season, the zooplankton move up or down within the water column to their preferred light conditions.
Read more at British Antarctic Survey
Image: Copepods form the largest part of the zooplankton. An egg-bearing female of the predatory copepod Paraeuchaeta sp. is shown here. (Credit: Alfred-Wegener-Institut / Mario Hoppmann)