Abstract
The Antarctic krill (Euphausia superba) fishery is the largest fishery in the Southern Ocean, and it has been operating for over 45 years. In the past decade, the spatial distribution of the krill fishery has focused on the Bransfield Strait off the Antarctic Peninsula (subarea 48.1). However, the high fishing effort and climate change have placed great pressure on krill resources in this region, and conservation concerns have been raised. Because aging krill is difficult and uncertain, we developed an integrated size-structured model to estimate the fishing mortality, recruitment and spawning biomass of krill. The results indicated that in 1992–2011, the average spawning biomass of krill ranged from 1.14 × 106 to 1.45 × 106 tons, the estimated biomass of the maximum sustainable yield (BMSY) ranged from 3.96 × 105 to 4.90 × 105 tons and the estimated average recruitment ranged from 2.3 × 1012 to 5.03 × 1012 individuals in the research area. We explored the effect of different data weighting schemes for the length data on the assessment output. However, our estimates also have uncertainties. In addition, an attempt was made to analyze the correlation between model-estimated recruitment and mature biomass with climate change. Future stock assessments of krill resources should be comprehensive and multimethod, and the management of krill resources should be based on science that considers the demand of fishing communities and ecosystem protection.
Highlights
The American naturalist James Dwight Dana gave an initial description of the Antarctic krill (Euphausia superba) in 1850
The study area includes the western side of the South Shetland Islands, the Bransfield Strait, and the water between Elephant Island and the Joinville Islands at the northern tip of the Antarctic Peninsula (Figure 1)
Under the three kinds of data weightings, there were some differences in the estimated recruitment of krill, but the trends were consistent The average levels of the estimated recruitment were 2.33 × 1012, 3.36 × 1012, and 5.16 × 1012, the highest estimated values were 3.58 × 1012, 5.76 × 1012, and 9.49 × 1012 in 1994, and the lowest estimated values were 1.47 × 1012, 1.81 × 1012, and 2.36 × 1012 in 1998
Summary
The American naturalist James Dwight Dana gave an initial description of the Antarctic krill (Euphausia superba) in 1850. Krill are considered to live for 5–7 years, the spawning population is 2–3 years old, and the adult body length is 40–65 mm (Ikeda, 1985). Due to the biological characteristics of molting and shortening body length when krill face adverse environments, determining their longevity is an unsolved and difficult scientific problem. The overall change in Antarctic krill resources will directly affect the resource status of other marine organisms in the Southern Ocean and play a key role in biogeochemical cycles such as carbon exports and the iron cycle. The Antarctic krill fishery is one of the key fisheries in the Southern Ocean, has high economic value and is of concern to many countries
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
