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Reporting reliable catch weight estimates is important for all fisheries management. This study explores the potential for precise and direct estimation of catch weight (green weight) for the Antarctic krill (Euphausia superba) fishery by employing a high frequency acoustic sensor in the trawl. Trials were performed off the coast of the South Orkney Islands during February 2020 using a scientific macroplankton trawl and echosounder providing a 18° beam pointing downwards across the fishing circle at the trawl mouth. The acoustically estimated catch weight and the observed catch weight had a linear relationship (R2 = 0.87, F(1,10) = 69.6, p < 0.000) where the acoustically estimated catch weight significantly predicted actual catch weight (β = 1.20, p = 0.000). The acoustic vertical densities of krill increased toward the center of the trawl opening suggesting that krill were herded during fishing. The current study demonstrates that acoustically based catch weight monitoring has the potential to be used for reporting total krill catch weight in each trawl, potentially in real-time, and that similar methods could also be employed in similar types of trawl fisheries.

Environmental monitoring along 5 set transect lines off South Orkney Islands in the Southern Ocean have been carried out annually (since 2011) by the Institute of Marine Research, Norway. Data are used to calculate biomass of Antarctic krill (Euphausia superba) as well as mapping distribution and demographic composition of krill, but also other macrozooplankton and fish taxa. Visual sightings of cetaceans and pinnipeds are registered systematically along the transects during daylight hours. During this year's survey, a pilot photo-drone project was also undertaken to investigate the potential of employing this type of technology to monitor body-size of individual whales to form the basis for calculating energetics and prey needs. Personnel were also deployed on Powell Island with breeding chinstrap penguins to satellite-tag penguins. At the same time, we maneuvered an unmanned sail drone, fitted with an echosounder, via satellite communication into what is known to be the preferred feeding area for chinstraps that breed at Powell Island. This data will be used to study swarm types in relation to penguins foraging strategies as well as assessing potential spatiotemporal overlaps with fisheries. Herein we report on the survey activities from 2023 and present some preliminary results. Antarctic krill and ecosystem monitoring survey off the South Orkney Islands in 2023

Estimates of the distribution and density of Antarctic krill (Euphausia superba Dana, 1850) were derived from a large-scale survey conducted during the austral summer in the Southwest Atlantic sector of the Southern Ocean and across the Scotia Sea in 2018–19, the ‘2018–19 Area 48 Survey’. Survey vessels were provided by Norway, the Association of Responsible Krill harvesting companies and Aker BioMarine AS, the United Kingdom, Ukraine, Republic of Korea, and China. Survey design followed the transects of the Commission for the Conservation of Antarctic Marine Living Resources synoptic survey, carried out in 2000 and from regular national surveys performed in the South Atlantic sector by the U.S., China, Republic of Korea, Norway, and the U.K. The 2018–19 Area 48 Survey represents only the second large-scale survey performed in the area and this joint effort resulted in the largest ever total transect line (19,500 km) coverage carried out as one single exercise in the Southern Ocean. We delineated and integrated acoustic backscatter arising from krill swarms to produce distribution maps of krill areal biomass density and standing stock (biomass) estimates. Krill standing stock for the Area 48 was estimated to be 62.6 megatonnes (mean density of 30 g m–2 over 2 million km2) with a sampling coefficient variation of 13%. The highest mean krill densities were found in the South Orkney Islands stratum (93.2 g m–2) and the lowest in the South Georgia Island stratum (6.4 g m–2). The krill densities across the strata compared to those found during the previous survey indicate some regional differences in distribution and biomass. It is currently not possible to assign any such differences or lack of differences between the two survey datasets to longer term trends in the environment, krill stocks or fishing pressure.

Increased and updated knowledge of reproductive strategies of fish is crucial to optimize the temporal and spatial planning for conducting seismic surveys; in order to reduce its potential negative ecosystems impacts. The overall goal of this study is to improve our knowledge about the spawning times of the major North Sea fish stocks.

Increased and updated knowledge of reproductive strategies of fish is crucial to optimize the temporal and spatial planning for conducting seismic surveys; in order to reduce its potential negative ecosystems impacts. The overall goal of this study is to improve our general knowledge about spawning areas of major North Sea fish stocks, including their spawning behavior and spawning period. This report describes the methodology, preliminary results and experiences gained during the data sampling period August 2017 to December 2019. Molecular barcode and traditional visual taxonomic analyses were performed on eggs and larvae, systematically collected with plankton nets along a south to north axis in the North Sea. In total, 201 samples have been analysed from which 35 different fish taxa are identified. Based on historic data and previously published literature, our results agree with the expected number of the most prevalent fish species breeding in the North Sea. Both the taxonomic and molecular methods used, demonstrate robust and similar results in the identification of taxonomic groups. The results further demonstrate that the molecular taxonomic approach is more appropriate for identification to species levels for most taxonomic groups, whilst the identification of egg and larvae developmental stages can only be performed using the visual taxonomic method. The two techniques have the potential of complementing each other to provide a detailed description of the annual fish spawning cycle for the main North Sea species. Our results demonstrate that the fish species diversity increase northwards, but here the spawning season is more concentrated. We have also identified new species spawning in the area, traditionally found more to the south or west of our study area. To improve the spatial and temporal statistical data resolution required for achieving sufficient scientific evidence as basis for producing robust advice in timing of seismic surveys, modifications to the sampling protocol and equipment was made during 2019. Expectantly, this potential proves to work over the coming annual reproduction cycle. Our study also confirms that the study area represents a highly dynamic environment, thus we strongly recommend considering extending the time period for data collection, beyond what is planned so far (due out August 2020) and an expansion of the geographical coverage to include regions also further north and west.

Increased and updated knowledge of reproductive strategies of fish is crucial to optimize the temporal and spatial planning for conducting seismic surveys; in order to reduce its potential negative ecosystems impacts. The overarching goal of this study is to investigate the current spawning times and locations for the North Sea fish stocks. Molecular barcode and traditional visual taxonomic analyses were performed on eggs and larvae, systematically collected with plankton nets along a south to north axis in the North Sea. This report describes the establishments of methodology employed and preliminary results based on samples collected during August 2017 to September 2018. In total, 129 samples have been analysed from which 22 different fish taxa are identified. Based on historic data and published literature, our results agree with the expected number of the most prevalent fish species breeding in the North Sea. Both the taxonomic and molecular methods used, demonstrate similar results in the identification of taxonomic groups. The results further demonstrate that the molecular taxonomic approach is more appropriate for identification to species levels for some taxonomic groups, whilst the identification of egg and larvae developmental stages can only be performed using the visual taxonomic method. The two techniques complement each other to provide a detailed description of the annual fish spawning cycle for the main North Sea species. There are already emerging patterns evident in the results on the timing for breeding in some species at certain areas. However, improvements of the sampling methodology are still required, and an increased number of samples collected systematically over an extended time-period must be accomplished in order to provide appropriate data as basis for advice in timing of seismic surveys.

Source at http://hdl.handle.net/11250/2600142 The primary objective for this krill research activity was twofold 1) to conduct a survey that provides updated estimates of the biomass and distribution of krill which are used in models to estimate sustainable yield in CCAMLR Area 48 and 2) to develop knowledge on the marine environment essential for the implementation of a Feed-Back Management (FBM) system. The survey follows a similar design as a survey initiated by CCAMLR in year 2000 for comparative purposes, but in addition focuses on high krill-density areas, contains state-of-the art methods and employs modern technology for the research topics currently in focus. In terms of FBM, Marine Protected Area (MPA) development in CCAMLR Planning Domain 1 encompasses the major krill fishing grounds. Thus, data supporting FBM are critical if the fishery is to be managed by an empirical understanding of krill density, distribution, availability and predator needs as opposed to purely conservation-based measures. A future developed FBM system, requires acoustic data to be collected, processed and reported continuously during the fishing season as a measure of the available prey field. This information can be integrated with finer-scale knowledge of krill predator feeding strategies and updated through specific scientific studies at regular (multiyear) intervals. The survey and coupled FBM process studies took place during the Austral summer 2018-2019. The work was coordinated by Norway and involved collaborative international efforts as well as vessels from Norway, Association of Responsible Krill fishing companies (ARK) and the Norwegian fishing company Aker BioMarine AS, China, Korea, Ukraine and United Kingdom. This report presents preliminary results from the survey performed with the Norwegian RV Kronprins Haakon during 08th January – 24th February 2019 and the land-based predator research carried out between 21st November 2018 and 20th February 2019.

The primary objective for this project is to develop knowledge on the marine environment essential for the implementation of a Feed-Back Management (FBM) system. In terms of FBM, Marine Protected Area (MPA) development in CCAMLR Planning Domain 1 encompasses the major krill fishing grounds. Thus, data supporting FBM as an integral part of the broader management strategies of the krill fisheries within Domain 1 are critical if the fishery is to be managed by an empirical understanding of krill density, distribution, availability and predator needs. A future developed FBM system, as presented in SC-CAMLR XXXVI/BG20 requires acoustic data to be collected, processed and reported continuously during the fishing season as a measure of the available prey field. This information can be integrated with finer-scale knowledge of krill predator feeding strategies and updated through specific scientific studies at regular (multiyear) intervals. The FBM process studies will take place during the Austral summer 2018-2019. Development of methods relevant to feedback management (FBM) for the krill fishery

The objective for the Multinational Large-Scale Krill Synoptic Survey in CCAMLR area 48 3 in 2019 is to provide an updated estimate of the biomass of Antarctic krill (Euphausia 4 superba) used in models to estimate sustainable yield. The planned survey follows, as close 5 as possible, the design of the CCAMLR 2000 survey, that was undertaken in the year 2000. 6 The basis for comparisons will depend on the degree of coverage and methodology and 7 equipment available. The survey will involve the collaborative efforts of Norway, 8 Association of Responsible Krill fishing companies (ARK: companies from Norway, Korea, 9 China and Chile), United Kingdom, Ukraine, Korea and China, and hopefully also other 10 nations that still needs to confirm their participation. 11 The current survey plan organization is presented for consideration by SG-ASAM. Norway 12 has volunteered to co-ordinate the survey with other members dedicating personnel to 13 specific tasks. It is requested that members who has already made commitments on ship time, 14 also allocate contact personnel as proposed. 15 This paper has been developed after a wider consultation extending beyond the authors list. It 16 discusses some specific organizational and technical challenges to be considered by SG17 ASAM. We request advice from ASAM on “minimum requirements” regarding acoustic 18 instrumentation and sampling gear to achieve approximate consistency with the CCAMLR 19 B0 data collection protocol. Multinational large scale krill synoptic survey in CCAMLR Area 48 in 2019-survey plan and protocol for consideration by SG-ASAM 2018

We carried out a survey of Antarctic krill (Euphausia superbaDana, 1850) from 2011 to 2015 to establish a long-term, time-series dataset of distribution, abundance, and demography for this species in the South Orkney Islands sector of the Southern Ocean. This species is abundant in this region and is subjected to high-intensity fishing, but previous assessments of density and population dynamics are few and outdated. Our data for Antarctic krill was collected from trawl stations along survey line transects covering the South Orkney plateau and shelf region during the summers of five consecutive years. We used concurrent data on hydrography, bathymetry, and proxies for algal biomass to describe potential spatial patterns of demography and abundance of E. superba. Comparative analysis of the demographic composition showed that 2012 differed from the other years by having a higher proportion of juveniles; otherwise a consistent pattern was found among years and within the study area. The highest biomass during the study period occurred along the northern shelf edge of the South Orkney Islands. Results of the linear mixed-effect model used to evaluate a diverse range of variables revealed that the only predictors for this hotspot were the short distance from land and great bottom depth. No clear differences in demographic composition for the study area were detected, which indicates that the area is highly dynamic and dominated by flux and advection of krill, both to, from, and within the area. Despite this finding, the results demonstrate that the shelf break on the northwest South Orkney Islands is predictable over time as a krill concentration and retention hotspot during the summer season. publishedVersion

The previously presented document at the 2018 ASAM WG meeting (ASAM-18-07) described a design and plans for a synoptic krill acoustic survey in CCAMLR area 48 in 2019. The survey involves the collaborative efforts of Norway, Association of Responsible Krill fishing companies (ARK: companies from Norway, Korea, China and Chile), the United Kingdom, Ukraine, Korea and China, all of whom have confirmed a commitment of survey ship time. With these commitments it is feasible to implement all transects occupied during the 2000 survey. This document is a draft survey manual, produced at the recommendation of the 2018 ASAM meeting, and describes acoustic procedures, acoustic reporting - analysis procedures and contingency plans. Acoustic manual for the krill synoptic survey in 2019

Experience gained through participation in international programmes like BIOMASS and the CCAMLR 2000 Survey has demonstrated that standardization of equipment and methods is one of the most crucial steps for any successful work during the field sampling period and later analytical work. The following net sampling and laboratory protocols are based on the protocols developed for the CCAMLR 2000 Survey. The aim is to facilitate a joint understanding of the field and laboratory work in order for participants that carry out the upcoming International Krill Synoptic Survey 2019 to collect comparable and highquality data. This will hopefully enable the establishment of a uniform and valuable database of comparable quality with data obtained through the CCAMLR 2000 Survey and other more recent surveys that have been conducted within the region of CCAMLR Area 48. Protocols for trawl sampling, recording of biological data, and hydrography for the 2019 international synoptic krill survey in Area 48