Prawn, Northern prawns, Northern shrimp

Pandalus borealis

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — North Sea (Norwegian Deep), Skagerrak and Kattegat
Stock detail — 4a, 3a
Picture of Prawn, Northern prawns, Northern shrimp

Sustainability rating four info

Sustainability overview

Updated: July 2019.

The stock is in an overfished state and fishing pressure is above sustainable levels, but reduced catches and high numbers of young prawns entering the fishery are expected to recover it to sustainable levels by 2020. There is a long term management plan in place for this stock, and some technical measures including closures when too many undersized prawns are being caught. Demersal trawling can have seabed impacts and catch vulnerable deep-sea species such as roundnose grenadier and sharks.

Biology

Pandalus borealis, the northern prawn, or cold-water prawn (also known as pink or deep-water shrimp in North America), are crustaceans belonging to the family Pandalidae. The species has a wide distribution throughout the North Atlantic and North Pacific Oceans (the Pacific form is generally regarded as a subspecies, Pandalus borealiseous). The species occurs as far south as the North Sea, Massachusetts, Oregon and Japan. Northern shrimp are hermaphroditic. They develop initially as males, then become female after around 3 years, and complete their lives as females. Life span is around 5 years, although possibly up to 8 years in northern latitudes. They spawn in autumn and females carry the eggs until April/May, when they hatch and the pelagic larvae are released. Total adult length is about 15 cm. This species inhabits areas of soft, muddy sediment with a depth range from 20-1300 m. Prawns migrate vertically at night to feed on zooplankton. Northern prawn are heavily predated on by fish and marine mammals.

Stock information

Criterion score: 0.75 info

Stock Area

North Sea (Norwegian Deep), Skagerrak and Kattegat

Stock information

The stock is in a poor state and fishing pressure is above sustainable levels, but catches in line with advice and high numbers of young prawns entering the fishery are expected to recover it to sustainable levels by 2020.

The spawning-stock biomass (SSB) declined after 2008 and has fluctuated at a lower level since then. SSB in 2019 is 6,377t, close to Blim (6,300t) and below sustainable levels (MSY BTrigger = 9,900t). Fishing mortality (F) in 2018 was 0.66. F has been above FMSY (0.6) every year since 2011, except in 2015. Recruitment has been below average since 2008, except for the 2013 and 2018 year classes.

In April 2018, a Long-Term Management Strategy (LTMS) was agreed by EU and Norway and ICES has evaluated it to be precautionary. The LTMS was implemented from 2019. ICES advises that when the LTMS is applied, catches in 2019 should be no more than 6,163 tonnes - a 28% decrease from the 8571 tonnes advised in 2018, owing to the decrease in SSB to close to BLim. This, and the strong recruitment of 2018, are expected to being SSB back to 9,952t in 2020. ICES also advise that catches for the first two quarters of 2020 should be no more than 6329 tonnes, with total catch for 2020 being around 12,439t. This doubling of advice from 2019 to 2020 is owing to the expected increase of SSB back to MSY BTrigger (assuming that catches are in line with advice). As northern prawns enter the fishery at age 1, catch options and short-term forecasts of SSB are strongly dependent on recruitment estimates.

Total Allowable Catches are split between areas 3a (Skagerrak and Kattegat) and 4a (Northern North Sea in the Norwegian Deep), and are generally set in line with advice. Actual catch usually falls in line with TACs.

Management

Criterion score: 0.5 info

There is a management strategy in place for setting TAC levels, which follows scientific advice. Some technical measures are in place to reduce discards, and others are being developed.

The stock within the North Sea is covered by the EU’s North Sea Multi Annual management Plan (MAP), and although the MAP has not been adopted by Norway, joint TACs are agreed through the EU-Norway Agreement. A Long-Term Management Strategy (LTMS) was agreed by EU and Norway in 2018 and implemented in 2019. ICES has evaluated it to be precautionary. It includes targets for F and B that follow ICES advice, and sets TACs for the year based on whether the stock is above or below MSY BTrigger. Total Allowable Catches (TACs) include all removals from the stock. ICES advises that when the LTMS is applied, catches in 2019 should be no more than 6,163 tonnes, and EU and Norway have set the 2019 TAC at this level, with an agreed split between the two parties. EU and Norway acknowledge some issues with adequate control and enforcement of cross-border fishing activities, and are looking into this. Technical measures are being developed, aimed at reducing discards, improving selectivity and harmonising where there are differences between the EU and Norway’s legislation. This includes a joint Real Time Closure: if more that 20% of at least 2 hauls in 96 hours, or 40% of one haul, is made up of undersize (below 6.5cm) prawns, the area in which they are caught (up to 50 sq. nautical miles) is closed for 14 days. This comes into force on 1st July 2019 and is in force across the EU-Norway border. Bottom trawls with mesh size of 35mm or more and a sorting grid with 19mm bar spacing at the top and 9.5mm bar spacing at the bottom (which allows small animals to escape the net) are allowed in the RTC.


In the European Union (EU), EU fishing vessels can fish up to 12 nautical miles of any Member State coast, and closer by agreement. There is overarching fisheries legislation for all Member States, but implementation varies between fisheries, Member States and sea basins.
The EU Common Fisheries Policy (CFP) is the primary overarching policy. Its key environmental objectives are to restore and maintain harvested species at healthy levels (above BMSY), and apply the precautionary and ecosystem-based approaches to fisheries management. To achieve the MSY objective, the MSY exploitation rate is supposed to be achieved by 2020, but this seems unlikely to happen.
The CFP also introduced a Landing Obligation (LO) which bans the discarding at sea of species which are subject to catch limits. Some exemptions apply to species with high post-capture survival, and where avoiding unwanted catches is very difficult. These exemptions are outlined in regional discard plans. Despite quota ‘uplift’ being granted to fleets under the LO, available evidence suggests there has been widespread non-compliance with the policy, and illegal and unreported discarding is likely occurring.
Multi-Annual Plans (MAPs) are a tool for implementing the CFP regionally, with one in place or being developed for each sea basin. They specify fishing mortality targets and ranges for the main targeted species, as well as lower biomass reference points. If populations drop below these points it should trigger a management response. The MAPs also empower Member States to jointly apply measures such as closures, gear or capacity limits, and bycatch limits. There is concern however that the MAPs do not provide adequate safeguards to maintain all stocks at healthy levels.
The EU Technical Measures regulation addresses how, where and when fishing can take place in order to limit unwanted catches and ecosystem impacts. There are common measures that apply to all EU sea basins, and regional measures that vary between sea basins. Measures include Minimum Conservation Reference Sizes (MCRS, previously Minimum Landing Sizes, MLS), gear specifications, mesh sizes, closed areas, and bycatch limits.
The Control Regulation, which is being revised in 2019, addresses application of and compliance with the above, e.g. keeping catches within limits, recording and sharing data, and satellite tracking of vessels over 12 metres (VMS).

Capture Information

Criterion score: 0.5 info

Shrimp trawling in this area regularly catches vulnerable deep sea species.

Northern shrimps are caught by trawling, mainly by 35-45 mm single- and twin-trawl nets (minimum legal mesh size 35 mm). Demersal nets may be towed between 2 boats as in pair-trawling, or one boat may tow more than one net as in twin or multi-rig otter trawling. It is not unknown for some boats to tow up to 8 or 10 nets. A large number of vessels use sorting grids, to reduce bycatch, on a voluntary basis. When sorting grids are not used bycatch species, dominated by saithe and cod, may constitute up to 30% of the landed catch. Deep-sea species, e.g. Argentines, roundnose grenadier, rabbitfish and sharks are frequently caught in shrimp trawls in the deeper parts of the Skagerrak and the Norwegian Deep. Legislation requiring a species-selective grid has been implemented in the Skagerrak since February 2013. Average discard rate was 13.5% in 2012-2014. Discards in 2017 were 15% of the total catch.

References

EU, 2019. EU-Norway Fisheries Consultation: Northern Prawn. London, 11 April 2019. Available at https://ec.europa.eu/fisheries/sites/fisheries/files/docs/body/2019-04-11-norway-fisheries-consultations-prawn_en.pdf [Accessed on 04.07.2019].

ICES. 2019. Northern shrimp (Pandalus borealis) in divisions 3.a and 4.a East (Skagerrak and Kattegat and northern North Sea in the Norwegian Deep). In Report of the ICES Advisory Committee, 2019. ICES Advice, pra.27.3a4a, doi: 10.17895/ices.advice.4892. Available at http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2019/2019/pra.27.3a4a.pdf [Accessed on 04.07.2019].