Halibut, Greenland

Reinhardtius hippoglossoides

Method of production — Caught at sea
Capture method — Gill or fixed net
Capture area — North East Atlantic (FAO 27)
Stock area — Iceland, Faroes, West of Scotland, North of Azores, East of Greenland
Stock detail — 5, 6, 12, 14
Picture of Halibut, Greenland

Sustainability rating four info

Sustainability overview

Updated November 2019.

Greenland halibut is a long-lived, low productivity species with low resilience to fishing pressure. The stock in this area is not overfished, but is subject to overfishing. There is an agreed management plan between Greenland and Iceland that aims to keep fishing pressure at sustainable levels through Total Allowable Catches, but this doesn’t adequately account for catches from the Faroe Islands EEZ, and total catches in the last 5 years have exceeded the advice by 10%, on average. The majority of Greenland halibut is caught by bottom trawling, and much of this activity takes place in the deep sea, i.e. below 600m. This is of concern as habitats at this depth are vulnerable to the impacts of bottom trawling.

The Icelandic ISF fishery for Greenland halibut is certified as sustainable by the Marine Stewardship Council. There are conditions on the certification to improve management through better Harvest Control Rules and more effective cooperation between all parties fishing the stock. Measures must also be implemented to protect all vulnerable marine habitats to ensure that the trawl fishery does not cause serious or irreversible harm to habitat structure, and some work has already been completed to improve monitoring on impacts on sponges and corals.

Biology

This is an Arctic species which feeds in mid-water. Unlike most other flatfish, its ‘blind side’ is dark grey rather than white. Greenland halibut spawns in summer (April to June). It is a relatively slow-growing and long-lived species. Males become sexually mature when 7-8 years old and 55-65 cm long and females when 9-11 years old and 65-80 cm. They move into deeper water as they grow and can reach lengths of 120cm. Maximum reported age 30 years.

Stock information

Criterion score: 0.5 info

Stock Area

Iceland, Faroes, West of Scotland, North of Azores, East of Greenland

Stock information

Greenland halibut is a long-lived, low productivity species with low resilience to fishing pressure. The biomass of the stock is currently above MSY BTrigger but is subject to overfishing.

Biomass reference points for this stock are measured as the ratio of biomass (B) to BMSY, and likewise fishing pressure is measured as the ratio of fishing pressure (F) to FMSY. Greenland halibut stock in this area steadily declined from 1960 (when B:BMSY = 2), dropping below BMSY in 1993, and since then has fluctuated between MSY BTrigger (B:BMSY=0.5) and BMSY. In 2019 it was 0.66 - the lowest level since 2010, but above the level at which management measures need to be triggered. Meanwhile, fishing pressure increased from 1960, exceeding FMSY in 1987 to peak in 1996 (when F:FMSY = 2.1). It has declined since then to fluctuate between FMSY and Flim (1.7) and in 2018 it was 1.34. The stock is therefore subject to overfishing, and F is at its highest level since 2005. There is high uncertainty in the estimates for fishing pressure, but the probability that overfishing has been taking place for most of the time series is high.

ICES advises that when the MSY approach is applied, catches in 2020 should be no more than 21,360 tonnes. This is a decrease of 12% from the previous year, owing to a decrease in estimated biomass.

Greenland halibut is a relatively slow-growing and late-maturing species. Low abundance of smaller fish has been recorded in the surveys in recent years, and these small year classes are now entering the fishable biomass, which is likely to cause an overall reduction in total biomass in the future. Since Greenland halibut is a slow-growing species that first appears in catches at ages 4-6, recruitment failure will only be detected some 5-10 years after it occurs.

The connectivity between this stock and the Barents Sea stock (ICES subareas 1 and 2) is unknown, but tagging experiments suggest high mixing. This adds to the uncertainty in the assessment and advice. Greenland halibut in ICES Subareas 5, 6, 12 and 14 are assessed as one stock unit although precise stock associations are not known. A workshop in August 2019 with trans-Atlantic participation from all major fishery research institutes aims to outline stock structure in the entire North Atlantic.

Management

Criterion score: 0.75 info

There is no management plan for the stock as a whole, and recent catches have been above the scientific advice. The stock is not in an overfished state, but is subject to overfishing.

The main country fishing for Greenland halibut in this area is Iceland, with (on average) 50% of catches over the past five years. Other countries include Germany (average 16%), Faroe Islands (15%), Greenland (10%), and Norway (4%). Total Allowable Catches (TACs) are set for Iceland’s and Greenland’s Exclusive Economic Zones (EEZ) - ICES areas 5a and 14, respectively. Since 2014 there has been a bilateral agreement between Iceland and Greenland, ensuring that their combined EEZ TACs reach 94% of the scientific advice, intended to keep fishing pressure close to FMSY. In the Faroe Islands EEZ (ICES 5b), the fishery is regulated by fixed numbers of licenses and technical measures, e.g. bycatch regulations for trawlers, and depth and gear restrictions for gillnetters. However, there is no agreed catch limit for the Faroes EEZ, and catches from this area exceed the 6% of the TAC that is not taken up by Iceland and Greenland. In 2018, quotas in Greenland EEZ and Iceland EEZ were fully utilized, as they have been in previous years. However, total catches in all areas were 27,000 tonnes - 20% higher than the scientifically recommended limit. While the TAC has limited fishing pressure compared to the levels it reached before 2014, on average in the past five years, catches have been 10% above recommended limits. With fishing pressure somewhat above FMSY, the management plan does not appear to be effective in keeping fishing pressure at sustainable levels. A Harvest Control Rule is expected to be developed by Iceland for Greenland halibut by 2020.

Discarding and bycatch are considered negligible. The mandatory use of sorting grids in the shrimp fishery in Iceland since the late 1980s, and in Greenland since 2002, has reduced bycatch of Greenland halibut considerably: based on sampling in 2006-2007, bycatch of halibut is estimated to be less than 1% by weight, compared to about 50% before the implementation of sorting grids. Reported discarding is less than 1% by weight.

The Icelandic ISF fishery for Greenland halibut is certified as sustainable by the Marine Stewardship Council. This fishery caught 9,282 tonnes of Greenland halibut in 2017/18, of which 8,750 tonnes was by demersal otter trawl. There is a condition on the certification to improve management through implementation of a Harvest Control Rule that reduces exploitation rates as limit reference points are reached, and to implement organised and effective cooperation between all parties that are fishing this stock (i.e. not just Greenland and Iceland, but the Faroes as well).

Capture Information

Criterion score: 0.5 info

In 2018, 64% of Greenland halibut landings were by bottom trawlers and shrimp trawlers, and 36% was by gillnet and longline.

About 50% of catches are by Iceland, and just over half of those are by trawl, with most of the rest by gillnet. Various measures are in place to protect small fish and vulnerable habitats, e.g. regulations on the type of fishing gear allowed in different areas, minimum mesh sizes, and small-fish sorting grids. If the percentage of small fish in the catch or the by-catch exceeds guideline limits, the relevant fishing area may be closed within a few hours. If small fish or by-catch repeatedly exceeds guideline limits, the relevant area is closed for a longer time. Time, area and gear closures are in place to protect redfish and other demersal species’ spawning grounds. Sharks and skates are taken as bycatch in Icelandic fisheries, but catch rates are incomplete and the status of stocks is unknown. The endangered Atlantic halibut is impacted by fisheries around Iceland, so a mandatory release of viable halibut and a landings ban were introduced in 2012.

In Greenland, around 80% of catches of Greenland halibut are from 800m or deeper. Fisheries are regulated through a system of licences that limits the target species, the area, the time of the year used for fishing and/or the amount of fish to be caught. There is a general ban on discarding, and all Greenlandic and foreign vessels operating in Greenland waters must record and report all catches, including birds and mammals, even if the vessels are below 6m. Large vessels are monitored through VMS, and an observer scheme aims for a minimum coverage of 50% of fishing trips in key fisheries and fisheries where there is a risk that one or more rules are not respected. It is forbidden to fish offshore with gillnets, to reduce the risk of lost fishing gear and subsequent ghost fishing, so the majority of offshore, deep-sea fishing is by bottom trawling. Trawling is almost entirely banned inshore, so the rest of the catch here is by gillnet and longline at depths of 300-600m. As of 2016, there were no records of by-catches of marine mammals in this fishery. There are a number of closed areas to trawling some to avoid conflicts between narwhal and beluga hunting and fishing, but it is not clear if any are designated to protect habitats.

In the North-East Atlantic Fisheries Commission (NEAFC) Regulatory Area, there are a number of closures to protect Vulnerable Marine Ecosystems from fishing, e.g. on the mid-Atlantic Ridge and in the Hatton-Rockall area.

The Icelandic ISF fishery for Greenland halibut is certified as sustainable by the Marine Stewardship Council. This fishery caught 9,282 tonnes of Greenland halibut in 2017/18, of which 8,750 tonnes was by demersal otter trawl.

Alternatives

Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Dab
Halibut, Atlantic (Farmed)
Megrim
Plaice
Sole, Dover sole, Common sole
Turbot (Caught at sea)
Turbot (Farmed)

References

Government of Greenland, 2017. Review of existing knowledge on marine mammal by-catch in Greenland. Report SC/24/BYC/14, The Government of Greenland Ministry of Fisheries & Hunting, May 2017. Available at https://nammco.no/wp-content/uploads/2018/11/fi-01-review-of-existing-knowledge-on-marine-mammal-by-catch-in-greenland-2017-draft.pdf [Accessed on 26.11.2019].

Government of Iceland, 2019. Statement on Responsible Fisheries in Iceland. Available at https://www.government.is/news/article/2018/05/15/Fisheries/ [Accessed on 25.11.2019]

ICES, 2013. Stock Annex: Greenland halibut (Reinhardtius hippoglossoides) in subareas 5, 6, 12, and 14 (Iceland and Faroes grounds, West of Scotland, North of Azores, East of Greenland). North Western Working Group (NWWG). Available at https://www.ices.dk/sites/pub/Publication%20Reports/Stock%20Annexes/2015/ghl-grn_SA.pdf [Accessed on 25.11.2019].

ICES, 2018. ICES Ecosystem Overviews: Icelandic Waters Ecoregion. Published 14 December 2018. doi: 10.17895/ices.pub.4669. Available at https://www.ices.dk/sites/pub/Publication%20Reports/Advice/2018/2018/IcelandicWatersEcoregion_EcosystemOverview.pdf [Accessed on 28.06.2019].

ICES, 2019. Greenland halibut (Reinhardtius hippoglossoides) in subareas 5, 6, 12, and 14 (Iceland and Faroes grounds, West of Scotland, North of Azores, East of Greenland). In Report of the ICES Advisory Committee, 2019. ICES Advice 2019, ghl.27.561214, https://doi.org/10.17895/ices.advice.4737. Available at http://ices.dk/sites/pub/Publication%20Reports/Advice/2019/2019/ghl.27.561214.pdf [Accessed on 25.11.2019].

ICES. 2019. North Western Working Group (NWWG). ICES Scientific Reports. 1:14. 638 pp. http://doi.org/10.17895/ices.pub.5298. Available at https://www.ices.dk/sites/pub/Publication%20Reports/Expert%20Group%20Report/Fisheries%20Resources%20Steering%20Group/2019/NWWG/01%20NWWG%20Report%202019.pdf [Accessed on 25.11.2019].

ICES. 2019. New information regarding vulnerable habitats in the NEAFC Regulatory Area. In Report of the ICES Advisory Committee, 2019. ICES Advice 2019, vme.neafc, https://doi.org/10.17895/ices.advice.5580. Available at http://ices.dk/sites/pub/Publication%20Reports/Advice/2019/2019/vme.neafc.pdf [Accessed on 26.11.2019].

MFRI, 2019. MFRI Assessment Reports 2019: Greenland Halibut - Graluda, Reinhardtius hippoglossoides. Marine and Freshwater Research Institute, 13 June 2019. Available at https://www.hafogvatn.is/static/extras/images/22-GreenlandHalibut_TR%20(1)1141511.pdf [Accessed on 26.11.2019].

MSC, 2019. ISF Greenland halibut. Available at https://fisheries.msc.org/en/fisheries/isf-greenland-halibut/@@assessments [Accessed on 26.11.2019].

NEAFC, 2014. Recommendation 19 2014: Protection of VMEs in NEAFC Regulatory Areas. Available at https://www.neafc.org/system/files/Rec.19-2014_as_amended_by_09_2015_and_10_2018_fulltext-and-map.pdf [Accessed on 26.11.2019].