Kaljuste, Olavi
- Department of Aquatic Resources (SLU Aqua), Swedish University of Agricultural Sciences
Conference paper2023Peer reviewed
Raid, Tiit; Arula, Timo; Sepp, Elor; Hommik, Kristiina; Kaljuste, Olavi; Strods, Guntars; Putnis, Ivars; Plikshs, Maris
Maximum sustainable yields and maintaining the intraspecific biodiversity are the aim in fish stock management. Here populations-based management would be the preferred practice. Yet available stock discrimination methods result in establishing the conventional assessment/management units as a compromise. The Baltic herring (Clupea harengus membras L.) exhibits remarkable geographical variabil-ity, forming up to12 local populations. Due to reasons mentioned above, only two distinct local populations (Gulf of Riga, (GoR) herring and Gulf of Bothnia herring), are treated as separate assessment and manage¬ment units. The paper describes the annual workflow of the management process, collection of the biological information from commercial catches and from the research surveys. Management history of GoR herring has revealed a number of challenges. Acoustic estimates are the only fisheries-independent data applied in GoR herring stock assessment. The study highlights the need for methodological changes what are expected to allow enhancing the quality of stock estimates, serving as the basis for the management decisions. We show that while before climate-driven regime shift (prior-1990s) recruitment was determined by the winter tem¬perature, affecting survival of Young of the year, a new major productivity bottleneck is in increasing spring-summer water temperatures during hatching and larval first-feeding stage.
Baltic herring; assessment; management; fishery; novel insights
Proceedings in Marine Technology and Ocean Engineering
2023, Volume: 9, pages: 411-420 Title: Sustainable Development and Innovations in Marine Technologies
ISBN: 9781032416182, eISBN: 9781003358961Publisher: CRC PRESS-TAYLOR & FRANCIS GROUP
19th INTERNATIONAL CONGRESS OF THE INTERNATIONAL-MARITIME-ASSOCIATION-OF-THE-MEDITERRANEAN (IMAM), SEP 26-29, 2022, Istanbul, TURKEY
Fish and Wildlife Management
DOI: https://doi.org/10.1201/9781003358961-51
https://res.slu.se/id/publ/129591