Figure 3.2.1a: Map of high throughput sequencing records from the Arctic Marine Areas. Figure 3.2.1b: Map of records of phytoplankton taxa using microscopy from the Arctic Marine Areas. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/plankton" target="_blank">Chapter 3</a> - Page 35 - Figure 3.2.1a and Figure 3.2.1b In terms of stations sampled, the greatest sampling effort of high-throughput sequencing in Arctic marine water columns, by far, has been in the Beaufort Sea/Amundsen Gulf region and around Svalbard. High through-put sequencing has also been used on samples from the Chukchi Sea, Canadian Arctic Archipelago, Baffin Bay, Hudson Bay, the Greenland Sea and Laptev Sea.

Sea ice amphipod (macrofauna) distribution and abundance across the Arctic aggregated from 47 sources between 1977 and 2012 by the CBMP Sea Ice Biota Expert Network. Bar graphs illustrate the frequency of occurrence (%) of amphipods in samples that contained at least one ice-associated amphipod. Red circles illustrate the total abundances of all ice-associated amphipods in quantitative samples (individuals m-2) at locations of sampling for each Arctic Marine Area (AMA). Number of sampling efforts for each region is given in parenthesis after region name. Blue dots represent samples where only presence/ absence data were available and where amphipods were present. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/sea-ice-biota" target="_blank">Chapter 3</a> - Page 44 - Figure 3.1.6 From the report draft: "This summary includes 47 data sources of under-ice amphipods published between 1977 and 2012. When available, we collected information on abundance or density (ind. m-2, or ind. m-3 that were converted to ind. m-2) and biomass (g m-2, wet weight). If abundance or biomass data were not available, we examined presence/relative abundance information. Frequency of occurrence was calculated for regions across the Arctic using integrated data for all available years."

In 2017, the SAMBR synthesized data about biodiversity in Arctic marine ecosystems around the circumpolar Arctic. SAMBR highlighted observed changes and relevant monitoring gaps using data compiled through 2015. In 2021 an update was provided on the status of seabirds in circumpolar Arctic using data from 2016–2019. Most changes reflect access to improved population estimates, orimproved data for monitoring trends,independent of recognized trends in population size.

Estimated consumption of polar cod by Atlantic cod in the Barents Sea (yellow line) and biomass of the Atlantic cod stock in the Barents Sea (red line) (ICES 2016). The blue line is the biomass of the Barents Sea polar cod (Prozorkevich 2016). STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/marine-fishes" target="_blank">Chapter 3</a> - Page 116 - Box figure 3.4.1

Workflow of the Circumpolar Biodiversity Monitoring Program (CBMP). STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/marine" target="_blank">Chapter 1</a> - Page 13 - Figure 1.1

Megafauna distribution of biomass (g/15 min trawling) in the Barents Sea in 2007, 2011 and 2015. The green circles show the distribution of the snow crab as it spreads from east to west, and the blue triangles show the invasion of king crab along the coast of the southern Barents Sea. Data from Institute of Marine Research, Norway and the Polar Research Institute of Marine Fisheries and Oceanography, Murmansk, Russia. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/benthos" target="_blank">Chapter 3</a> - Page 95 - Figure 3.3.2 The annual joint Norwegian–Russian Ecosystem Survey provides from more than 400 stations and during extensive cruise tracks covering more or less the whole Barents Sea in August– September. The sampling is based on a regular grid spanning about 1.5 millionkm2 with fixed positions of stations which make it possible to measure changes in spatial distribution over time. The trawl is a Campelen 1800 bottom trawl rigged with rock-hopper groundgear and towed on double Warps. The mesh size is 80 mm (stretched) in the front and 16–22 mmin the cod end, allowing the capture and retention of smaller fish and the largest benthos from the seabed (benthic megafauna). The horizontal opening was 11.7 m, and the vertical opening 4–5 m (Teigsmark and Øynes, 1982). The trawl configuration and bottom contact was monitored remotely by SCANMAR trawl sensors. The standard distance between trawl stations was 35 nautical miles (65 km), except north and west of Svalbard where a stratified sampling was adapted to the steep continental shelve. The standard procedure was to tow 15 min after the trawl had made contact with the bottom, but the actual tow duration ranged between 5 min and 1 h and data were subsequently standardized to 15 min trawl time. Towing speed was 3 knots, equivalent to a towing distance of 0.75 nautical miles (1.4 km) during a 15 min tow. The trawl catches were recorded using the same procedures on the Russian and the Norwegian Research vessels to ensure comparability across Barents Sea regions. The benthic megafauna was separated from the fish and shrimp catch, washed, and sorted to lowest possible taxonomic level, in most cases to species, on-Board the vessel. Species identification was standardized between the researcher teams by annually exchanging the benthic expert’s among the vessels and taxon names were fixed each year according toWORMSwhen possible.This resulted in an Electronic identification manual and photo-compendium as a tool to standardize taxon identifications, in addition to various sources of identification literature. Difficult taxa were photographed and, in some cases, brought back as preserved voucher specimens for further identification. Wet-weight biomass was recorded with electronic scales in the ship laboratories for each taxon.The biomass determination included all fragments.

Circumpolar depiction of species richness based on the distributions of the 11 ice-associated Focal Ecosystem Components (according to the distributions reported in IUCN Red List species accounts). A maximum of nine species occur in any one geographic location. The Arctic gateways in both the Atlantic and Pacific regions have the highest species diversity. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/marine-mammals" target="_blank">Chapter 3</a> - Page 152 - Figure 3.6.1

Global catches of Greenland halibut (FAO 2015). STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/marine-fishes" target="_blank">Chapter 3</a> - Page 121 - Figure 3.4.8