Alaska pollock

The Alaska pollock stock in the Sea of Okhotsk is in a good state but fishing pressure is above sustainable limits.The pollock fishery in the Sea of Okhotsk has existed for around 55 years and catches have fluctuated considerably over that time. Since 2002, the catch has been relatively evenly distributed among the three subzones: Northern Sea of Okhotsk, western Kamchatka and Kamchatka-Kuril. Recent catches have been around 950,000 tonnes.The most recent stock assessment was carried out in 2021 by VNIRO, the All-Russian Research Institute for Fisheries and Oceanography. No additional updates have been released about this stock. However, MSC surveillance audit report indicates that spawning stock biomass continues to be above biomass targets.Spawning stock biomass (SSB) was below safe biological levels (Blim, 2.583 million tonnes) in the 1960s, at around 2 million tonnes. It subsequently increased to around 7 million tonnes in the 1980s and 1990s before rapidly declining to Blim again in the early 2000s. It has shown a steady increase since then and has been above target levels (Btr, 5.089 million tonnes) since the late 2000s. There is too much uncertainty to confirm what the biomass level associated with Maximum Sustainable Yield (MSY) should be, but Btr is considered a reasonable proxy for it. SSB in 2020was 6.9 million tonnes, and projections indicate that it will decline slightly to 6.2 million tonnes in 2022. This is a slight decline from recent levels but still 22% above target levels. Therefore, the stock is not in an overfished state.Fishing mortality (F) has fluctuated significantly over the years, often exceeding upper limits that are set to protect the stock from overfishing (Flim, 0.305). F was above this level in 2019 but has since declined. In 2020, the most recent year available, F was estimated to be 0.273. This is below Flim but 16% above the level associated with Maximum Sustainable Yield (Ftr, 0.235), and above the halfway point between Flim and Ftr. Therefore, this stock is subject to overfishing and there is concern for the fishing level.Recruitment of young fish into the stock fluctuates. Assuming recent average levels, it is projected that the stock will decline slightly until 2024, and then increase again. It is not predicted to fall below the target level.

A number of appropriate management measures are in place. However, there are some concerns about the bycatch of juveniles. The Sea of Okhotsk fishery has been Marine Stewardship Council (MSC) certified since 2013.In the Sea of Okhotsk there are four management subzones: the North Okhotsk Sea, western Kamchatka, Kamchatka-Kuril (which are all part of the Sea of Okhotsk), and eastern Sakhalin. Only the first three areas are covered by this rating, as eastern Sakhalin is a separate stock. The MSC-certified component of the fishery is responsible for 80-90% of pollock catches in this area. There are no conditions that require improvements, but there are some recommendations. These relate to getting stock assessments independently reviewed, improving observer coverage, and employing extra measures to reduce seabird bycatch.The fishery is managed by the Russian Federal Fishery Agency (FFA) using a range of management measures, including: licensing, catch limits (Total Allowable Catches, TACs), closed seasons, gear and area restrictions, bycatch and juvenile catch limits, and move-on rules. Trawling is not permitted within 30 miles of the mainland, and 5-12 miles from islands.The FFA sets TAC limits for each management sub-area based on the recommendations given by the TINRO (Pacific Fisheries and Oceanography Institute, Vladivostok. A Harvest Control Rule (HCR) with target and limit reference points has been established for the stock. The components of the harvest strategy are reviewed and improved as necessary through an annual multi-stage internal and external review process. The harvest strategy is reviewed at least every five years and improved as necessary. If the catch is in excess of the TAC, the management authority can enforce time-area closures. TACs appear to be in line with scientific advice. A TAC of 1,0232 million tonnes was advised for 2022. The TAC finally set was a 7% lower than the recommendation (956,000t).Catches of juveniles can be up to 20% of the total catch (by number). If this limit is surpassed, the vessel must notify the management agency and move on from the area. Pelagic trawls are designed to allow juvenile pollock (less than 35cm) to escape through selectivity panels. While the use of this insert has proved to be effective, concerns remain about the catch of juveniles. There is a risk of illegal discards after the 20% limit has been reached. In 2019, TINRO calculated that the North Okhotsk pollock harvests exceeded official tallies by 33.4% after juvenile discards were included in the calculations. In 2019, more than 400 notifications of juvenile bycatch overrun of the 20% were received. PINRO is developing a design for a new pelagic trawl selectivity mirror insert to reduce the bycatch of juveniles in the fishery.All vessels have Vessel Monitoring Systems (VMS) installed and there is a daily catch reporting log. In the certified Sea of Okhotsk pollock trawl fishery, scientific observer coverage has increased from 4.2% of fishing operations in 2016 to 20% in 2021, covering 91% of the catch by volume.Vessels, trawling operations, and catches are observed by scientific observers from fishery research institutes, Coast Guard inspectors and FFA inspectors. The cross-referencing system in place between data systems and inspections suggests that there is little scope for misreporting of retained catches or discarding.

Most pollock is caught by mid-water trawling. There are no known habitat impacts, and bycatch is low.The industrial fishery for pollock in the Sea of Okhotsk is carried out by vessels of mainly large or medium tonnage, operating mid water trawls off the seabed.Mid-water trawl does not contact with the bottom and therefore, has minimal negative impact on the benthic ecosystem. Spatial restrictions have been set and trawling may not be conducted less than 30 miles offshore and 5-12 miles from islands.The fishery targets pollock aggregations with midwater trawls using 100 mm mesh nets. According to the most recent bycatch data, pollock makes up 95% of the catch in the North of Okhotsk fishery. Other species found in the catch include: herring, Greenland halibut and Bering flounder.All bycatch must be recorded and reported. There are regulations in place to reduce bycatch, including temporal and spatial closures. For example, if bycatch exceeds 2% of the pollock catch, the excess catch must be discarded and the vessel must relocate at least 5 miles from the area. Due to a low volume of bycatch species, there is not thought to be a biological threat to other pelagic species from this fishery.Interactions with Steller sea lions have been reported in the fishery. Rookeries and haul outs have been protected in the area to minimise the impact of the fishery on the species. The population of the species has increased in the Northern Sea of Okhotsk and Sakhalin Island areas but decreased in other areas, resulting in an overall decreasing in abundance.Interactions with seabirds have been noted, but mortality is thought to be less than 0.1%. Therefore, there are unlikely to be population-level effects.