Supplementary material from "Plasticity and seasonality of the vertical migration behaviour of Antarctic krill using acoustic data from fishing vessels" ...

• Main Authors: Bahlburg, Dominik, Hüppe, Lukas, Böhrer, Thomas, Thorpe, Sally E., Murphy, Eugene J., Berger, Uta, Meyer, Bettina
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: The Royal Society 2023
• Subjects: Environmental Science; Ecology; FOS Biological sciences; Animal Behaviour; Antarc*; Antarctic; Antarctic Krill; Southern Ocean
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.6837508; https://rs.figshare.com/collections/Supplementary_material_from_Plasticity_and_seasonality_of_the_vertical_migration_behaviour_of_Antarctic_krill_using_acoustic_data_from_fishing_vessels_/6837508

Understanding the vertical migration behaviour of Antarctic krill is important for understanding spatial distribution, ecophysiology, trophic interactions and carbon fluxes of this Southern Ocean key species. In this study, we analysed an eight-month continuous dataset recorded with an ES80-echosounder on board a commercial krill fishing vessel in the southwest Atlantic sector of the Southern Ocean. Our analysis supports the existing hypothesis that krill swarms migrate into deeper waters during winter but also reveals a high degree of variability in vertical migration behaviour within seasons, even at small spatial scales. During summer, we found that behaviour associated with prolonged surface presence primarily occurred at low surface chlorophyll a concentrations whereas multiple ascent-descent-cycles per day occurred when surface chlorophyll a concentrations, were elevated. The high plasticity, with some krill swarms behaving differently in the same location at the same time, suggests that krill ...