Driving forces of Antarctic krill abundance

Antarctic krill, crucial to the Southern Ocean ecosystem and a vital fisheries resource, is endangered by climate change. Identifying drivers of krill biomass is therefore essential for determining catch limits and designating protection zones. We present a modeling approach to pinpointing effects o...

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Bibliographic Details
Published in:Science Advances
Main Authors: Ryabov, Alexey, Berger, Uta, Blasius, Bernd, Meyer, Bettina
Format: Article in Journal/Newspaper
Language:unknown
Published: American Association for the Advancement of Science (AAAS) 2023
Subjects:
Online Access:https://epic.awi.de/id/eprint/58179/
https://epic.awi.de/id/eprint/58179/1/2023,%20Ryabov%20et%20al%202023.pdf
https://doi.org/10.1126/sciadv.adh4584
https://hdl.handle.net/10013/epic.1fbf5d58-9ca4-4d76-a700-83c5e0a4f929
Description
Summary:Antarctic krill, crucial to the Southern Ocean ecosystem and a vital fisheries resource, is endangered by climate change. Identifying drivers of krill biomass is therefore essential for determining catch limits and designating protection zones. We present a modeling approach to pinpointing effects of sea surface temperature, ice cover, chlorophyll levels, climate indices, and intraspecific competition. Our study reveals that larval recruitment is driven by both competition among age classes and chlorophyll levels. In addition, while milder ice and temperature in spring and summer favor reproduction and early larval survival, both larvae and juveniles strongly benefit from heavier ice and colder temperatures in winter. We conclude that omitting top-down control of resources by krill is only acceptable for retrospective or single-year prognostic models that use field chlorophyll data but that incorporating intraspecific competition is essential for longer-term forecasts. Our findings can guide future krill modeling strategies, reinforcing the sustainability of this keystone species.