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The International Bottom Trawl Survey Working Group (IBTSWG) coordinates fishery-independent bottom trawl surveys in the ICES area in the Northeast Atlantic and the North Sea. These long-term monitoring surveys provide data for stock assessments and facilitate examination of changes in fish distribution and relative abundance. The group also promotes the standardization of fishing gears and methods as well as survey coordination. This report summarizes the national contributions in 2021–2022 and plans for the 2022–2023 surveys coordinated by IBTSWG.In the North Sea, the surveys are performed in quarters (Q) Q1 and Q3, while in the Northeast Atlantic the surveys are conducted in Q1, Q3, and Q4 with a suite of 14 national surveys covering a large area of continental shelf that extends from the north of Scotland to the Gulf of Cádiz. North Sea surveys in 2022-Q1 were affected severely by mechanical and COVID-related issues, as well as the number of storms experienced during the survey period. Some of the ICES rectangles in the survey area could not be sampled and a larger number of the rectangles were only sampled with a single tow.North Sea surveys in 2021-Q3 were broadly complete, with the wider area surveyed and comparable number of hauls. However, some rectangles close to shore or with obstructions may not have had full coverage.Most of the surveys in the Northeast Atlantic were completed successfully. However, the two Spanish groundfish surveys in the Gulf of Cádiz could not be undertaken in 2021. Vessel-related problems also affected the Spanish survey of the Cantabrian Sea, although this survey was completed using two vessels over a more protracted survey window. The IBTSWG welcomed the return of the Portuguese groundfish survey (Q4) after a two-year absence, with the survey being undertaken by the new research vessel, the “Mario Ruivo”.IBTSWG discussed the roadmap for the new survey trawl, following on from the Workshop on the Further Development of the New IBTS Gear (WKFDN). IBTSWG agreed the main aspects of the new trawl, and will meet intersessionally to discuss and agree the final net plans. Trials are planned to start in late 2022 with the subsequent introduction of the trawl in the North Sea over the next few years.IBTSWG met with members of various assessment groups, including the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak (WGNSSK) and the Working Group for the Bay of Biscay and the Iberian Waters Ecoregion (WGBIE) to discuss how closer cooperation could enhance the use of data outcomes. IBTSWG members subsequently gave presentations to some of the assessment working groups using the data collected under the auspices of IBTSWG and intends to incorporate feedback into the its work.The trawl surveys coordinated by IBTSWG also provide an important platform for the collection of additional data, including the sampling of sprat larvae, fish stomachs and fish parasites.

Assessing and improving the status of biodiversity are main targets of international agreements such as the Convention on Biological Diversity and the associated Aichi Biodiversity Targets for 2020. Here we present fish data from the Barents Sea Ecosystem Survey 2004-2019 on a format suitable for biodiversity assessments. The Barents Sea Ecosystem Survey is run jointly by the Institute of Marine Research (IMR, Norway) and the Polar Research Institute of Marine Fisheries and Oceanography (PINRO, Russia) - since 2019 - Polar Branch of Russian Federal Research Institute of Fisheries and Oceanography (VNIRO). We present a Barents Sea Fish Species Reference List that we use with the software StoX version 3.0 to translate and export data from raw data xlm -files in the NMDBiotic v3 format stored at IMR to a format suitable for diversity analysis. Finally, we present some example results based on the fish data from the Barents Sea ecosystem survey 2004-2019.

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.

This report presents the main results from the surveys in January-March 2018. The surveys were performed with the Norwegian research vessels “Helmer Hanssen” and “Johan Hjort” and Russian research vessel “Fritjof Nansen”. Annual survey reports since 1981 are listed in Appendix 1, and names of scientific participants are given in Appendix 3.

This report presents the main results from the surveys in January–March 2017. The surveys were performed with the Norwegian research vessels “Helmer Hanssen” and “G.O. Sars”. Annual survey reports since 1981 are listed in Appendix 1, and names of scientific participants are given in Appendix 3.

The Barents Sea is one of nine shelf ecosystem survey bordering the Arctic Basin. The Arctic region is warming faster than the rest of the world. In the Barents Sea the years since 2000 were the warmest since the onset of regular measurements (1900, Bochkov 1982, ICES 2016) and paleo-records based on foraminifera even suggest that the Atlantic Water flowing into to the Barents Sea area was at its warmest for the last 2000 years (Spielhagen et al. 2011). As a result the extent of Arctic Water with sub-zero temperatures and sea ice is shrinking in the Barents Sea (e.g. ICES 2016). The changes in hydrographic conditions change the conditions for the poorly known Arctic fish fauna in the region. Here we present for the first time results on trends in abundance and distribution of demersal Arctic fishes in the northern Barents Sea.

Since 1994 a depth stratified annual bottom trawl survey was conducted along the continental slope (68-80°N, 400-1500 m) using chartered factory trawlers. The main focus since the start of the series was to describe the adult population of the Greenland halibut (Reinhardtius hippoglossoides) stock in this area. Recently the survey also targeted deepwater by-catch species. In 2011 the Institute of Marine Research developed a long-term survey strategy for deep-sea fish surveys in which the previous trawl survey series was maintained, but renamed EGGA NORD and continued on a biannual frequency starting in 2011. Since the precision of the abundance and biomass estimates were expected to be low even after a substantial reduction in sampling effort (CV expected to be c. 15%), the strategy recommended a 50% reduction in number of stations. In 2013, 103 pre-selected sampling sites on the shelf-break and upper continental slope were allocated (20 min standard tows at 3 knots), and 100 actually trawled successfully. In addition, 18 sites were selected in the adjacent Bear Isle Channel of the SW Barents Sea. Due to technical problems with deck machinery the cruise was interrupted prematurely and only 12 of these sites were trawled. Preliminary results from the 2013 survey show a biomass estimate for Greenland halibut close to the average for previous years. Length distributions of Greenland halibut were similar to that in 2011. Only minor catches of Greenland halibut occurred in the Bear Isle Channel where Sebastes mentella was the dominant species.

Også publisert på regjeringen.no med innledning av Olje- og energidepartementet Resultatene fra et tokt med ”G.O. Sars” på Jan Mayenryggen i oktober 2011 blir sammenstilt med våre andre overvåkingsdata og info fra litteraturen. Hensikten med prosjektet er å beskrive miljø og marine ressurser på sokkelen sør for Jan Mayen. Dette er et område preget av store sesongmessige variasjoner med rike forekomster av plankton, pelagisk fisk, sjøfugl og sjøpattedyr i sommerhalvåret. Bunnfaunaen er preget av fjærestjerner, lærkoraler, ålebrosmer og ringbuk. Det ble funnet en ny fiskeart for norske farvann, glattpaddeulke.