Wind-Driven Variability in Larval Krill Connectivity: Implications for Spawning and Nursery Ground Linkages along the Western Antarctic Peninsula

This content is part of the manuscript “Modeled Connectivity of Antarctic Krill Spawning and Nursery Grounds along the Western Antarctic Peninsula”, currently under review in Marine Ecology Progress Series. This study uses a circumpolar regional ocean model with embedded Lagrangian drifters to investigate the physical drivers of larval krill transport into the Bransfield Strait nursery area. The drifter simulations incorporate key biological processes, including the embryo-larval descent–ascent cycle and diel vertical migration. We found that summer wind regimes strongly influence whether larvae reach the Bransfield Strait nursery ground via the continental shelf and Boyd Strait or via advection from the northwestern Weddell Sea around Joinville Island. These results underscore the importance of capturing interannual variability in environmental forcing and larval behavior in connectivity models. Our findings support the development of the Krill Stock Hypothesis by identifying key source-sink relationships and suggest the northwestern Weddell Sea may be an underappreciated spawning or nursery area. This work builds on prior submissions (WG-EMM-2023/02; SC-CAMLR-43/BG/27) and provides insights relevant to spatial management, conservation planning, and refinement of krill monitoring priorities under climate change.