Sole, Dover sole, Common sole

Solea solea

Method of production — Caught at sea
Capture method — Beam trawl
Capture area — North East Atlantic (FAO 27)
Stock area — North Sea
Stock detail

4.b, c


Certification

Marine Stewardship Council (MSC)


Picture of Sole, Dover sole, Common sole

Sustainability rating two info

Sustainability overview

The stock assessment in 2018 indicated the biomass of common sole in the North Sea was healthy yet fishing mortality a little above the level associated with the Maximum Sustainable Yield (FMSY). The Hastings Fleet Dover sole fishery and the Cooperative Fishery Organisation (CVO) North Sea plaice and sole fishery were certified by the Marine Stewardship Council (MSC) as environmentally responsible or sustainable fisheries in July 2009 and December 2012 respectively. Avoid eating immature sole (less than 30cm) and fresh (not previously frozen) fish caught during the breeding season (April-June).

Biology

Sole is a right-eyed flatfish (eyes on the right hand side of the body) and belongs to the family of flatfishes known as Soleidae. It spawns in spring and early summer in shallow coastal water, from April to June in the southern North Sea, from May-June off the coast of Ireland and southern England, and as early as February in the Mediterranean. Common sole become sexually mature at 3-5 years, when 25-35cm long, the males being somewhat smaller than the females. It can attain lengths of 60-70cm and weigh 3kg.The maximum reported age is 26 years. Sole is a nocturnal predator and therefore more susceptible to capture by fisheries at night than in daylight.

Stock information

Criterion score: 0.25 info

Stock Area

North Sea

Stock information

The spawning-stock biomass (SSB) has increased since 2007 and has been estimated at above MSY Btrigger since 2012. Fishing mortality (F) has declined since 1999 and is close to FMSY in 2017. Recruitment (R) has fluctuated without trend since the early 1990s, but without the large year classes that occurred in the preceding period.
ICES assesses that fishing pressure on the stock is above FMSY but within the EU Multiannual Plan (MAP) range and below Fpa and Flim; and spawning-stock size is above MSY Btrigger, BMGT, Bpa, and Blim.
ICES advises that when the proposed MAP for the North Sea is applied, catches in 2019 should be between 7451 tonnes and 21 644 tonnes, but according to the MAP, catches higher than those corresponding to FMSY (12 801 tonnes) can only be taken under certain conditions.

Management

Criterion score: 0 info

The EU adopted a management plan for flatfish in the North Sea in June 2007 which has been evaluated by ICES as precautionary. The EU is finalising a multi-annual plan for the North Sea. According to the MAP, catches higher than those corresponding to FMSY (12 801 tonnes) can only be taken under conditions specified in the MAP.

Capture Information

Criterion score: 0.75 info

In the southern North Sea sole are mainly caught by beam trawlers in mixed fisheries with plaice and other flat fish using 80 mm mesh nets. In other areas the mesh size for mobile fishing gears is 100 and 120 mm. The smaller minimum mesh size in the mixed flatfish beam trawl fishery in the southern North Sea means that large numbers of undersized plaice and cod (which are currently under a recovery plan) are discarded. The introduction of measures to reduce discarding such as larger mesh sizes, larger landing sizes and additional measures to protect juvenile fish should be implemented to increase the sustainability of this fishery. An increase in minimum mesh size will reduce discards of juvenile plaice and cod, however it would also lead to a loss of marketable sole. Discards of sole are in the order of 9%. Minimum conservation reference size for sole in EU waters is 24cm.

Choosing fish caught by more selective methods, e.g. gill, fixed net or seine net, can help reduce the negative impacts associated with beam trawling in this area. Ensure fixed nets are ‘dolphin friendly’. See Fishing Methods for information. Avoid eating immature sole (less than 30cm) and fresh (not previously frozen) fish caught during the breeding season (April-June).

Between 2014 and 2017 the use of pulse trawls in the main fishery operating in the North Sea has increased and less vessels are operating with traditional beam trawls. The pulse gear allows fishing of softer grounds and as a result the spatial distribution of the main fisheries has changed. Consequently, a larger proportion of the sole catch is now taken in the southern part of the area.

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)
Halibut, Pacific
Megrim
Plaice
Sole, Dover sole, Common sole
Sole, Lemon
Turbot (Caught at sea)
Turbot (Farmed)

References

ICES 2018. ICES Advice on fishing opportunities, catch, and effort Greater North Sea Ecoregion. Published 29 June 2018. Available at: http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2018/2018/sol.27.4.pdf (Accessed July 2018)