Pressemelding -
Zooplankton tracking with optical tools to map foraging grounds of little auks
The CliN-BluFeed project, financed by the Sustainable Blue Economy Partnership (SBEP), has a delivery in the form of a master thesis from the Polish research i IOPAN. The focus in the thesis is on the combined use of two complementary high-resolution optical tools to track copepods, the main prey for the little auk seabird.
Energy-rich copepods, particularly Calanus spp., play a key role as a primary food source for gelatinous zooplankton, fish, and seabirds. These copepods often form dense patches that attract predators—but detecting these aggregations remains a challenge with traditional net-sampling methods.
Master student Anna Jasina during fieldwork at Svalbard (Photo: Maja Trochanowska)
To better understand the foraging grounds of little auks on a broader scale, master student Anna Jasina employed two complementary high-resolution optical tools: a Laser Optical Plankton Counter (LOPC) and an Underwater Vision Profiler (UVP6). By combining these methods, Anna was able to provide detailed in situ assessments of the abundance and morphology of Calanus-type zooplankton.
Anna Jasina mounting the Underwater Vision Profiler 6 (UVP6) during fieldwork at Svalbard (Photo credit: Maja Trochanowska)
The research compared findings from two contrasting years—an exceptionally warm 2023 and a cooler 2024—as well as across distinct oceanographic domains (Arctic vs. Atlantic water masses). The results revealed strong temporal and environmental variability, underscoring the need for consistent, long-term monitoring using automated, high-resolution technologies to accurately assess the quality of little auk foraging habitats.
Little auks overlooking their foraging grounds at Svalbard (Photo: © Cornelius Nelo)
The study demonstrated the powerful potential of optical methods for tracking Calanusavailability for predators. When integrated with ancillary data—such as hydrography (temperature, salinity), chlorophyll concentration, and particle dynamics (e.g., marine snow) —these tools provided new insights into the ecological quality of suspended particles and plankton, enhancing our understanding of predator-prey interactions in the marine environment.
The title of the thesis is: CHARACTERISTICS OF PLANKTIVOROUS LITTLE AUKS’ FEEDING GROUNDS ON THE WESTERN SPITSBERGEN SHELF – ASSESSED BY MODERN OPTICAL TOOLS
Anna Jasina has been supervised by Emilia Trudnowska from the Institute of Oceanology Polish Academy of Sciences (IOPAN).
The Clin-BluFeed project is led by Akvaplan-niva in Norway and the partners are IOPAN, CSCS, AIR Centre - Atlantic International Research Centre,and Alfred Wegener Institute (AWI).
Read more about the project: https://akvaplan.no/en/project...