Bass, seabass (Caught at sea)

Dicentrarchus labrax

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — Bay of Biscay (North and Central)
Stock detail — 8a, 8b
Picture of Bass, seabass (Caught at sea)

Sustainability rating three info

Sustainability overview

Updated: July 2020

The seabass stock in the north and central Bay of Biscay, is in a good state and fishing pressure has recently reduced, and now within sustainable levels. Stock identity remains poorly understood and further studies (including tagging, genetics, or other types of markers) are needed. The combination of slow growth, late maturity, spawning aggregation and strong site fidelity, increase the vulnerability of seabass to overexploitation and localized depletion. The EU multiannual plan for stocks in the Western Waters and adjacent waters applies to this stock. ICES considers the plan to be precautionary. Seabass are not subject to EU TACs (Total Allowable Catch) or quotas, and are caught both commercially and recreationally. Landings have been in line with advice in recent years, but as a non-TAC species there is potential for displacement of fishing effort from other species with limiting quotas, as observed with netters in Bay of Biscay, reporting their catches from sole to seabass. With no effective limits to control the fishery, there can be risks to increase landings as observed in 2014. Seabass are caught using a variety of fishing gears (e.g. gillnet, hook and line, trawl and seine), some of which, can have high levels of bycatch of non-target species, and habitat impacts upon the seabed, by abrasion and smothering in this ecoregion. Pelagic trawling in the Bay of Biscay is associated with concerning levels of dolphin bycatch and mortality, particularly of common dolphin. Harbour porpoises are being caught as bycatch off Iberia in set-nets to the extent that the local population of the species may become extinct.

Biology

Bass or seabass belongs to a family of spiny-finned fish called Moronidae, which are closely related to groupers. Bass breed from March to mid-June, mostly in April, in British coastal and offshore waters, from January to March in the Bay of Biscay and from February to May in the English Channel and eastern Celtic Sea. It is a long-lived and slow growing species - up to 30 years of age - and can achieve a length of up to 1m with a weight of 12kg. Male bass mature at 31-35cm (aged 3-6 years) and females mature at 40-45cm (aged 5-8 years). Once mature, bass may migrate within UK coastal waters and occasionally further offshore. Increases in sea water temperature in recent decades has likely led to a more northerly distribution of seabass, as it is now found further north into the North Sea. Climate warming may also have lengthened the time adult seabass spend in the summer feeding areas. After spawning, seabass tend to return to the same coastal sites each year.

Stock information

Criterion score: 0.25 info

The stock is in a good state and fishing pressure has come down, which is now within sustainable limits.

The spawning-stock biomass (SSB) has been declining since 2010, in 2020 it was 18,294 tonnes. SSB is now just above MSY Btrigger (16,688 tonnes). In 2020, the ratio of B:BMSY was 1.1. Fishing mortality (F) has fluctuated around the Maximum Sustainable Yield (FMSY) (0.123) since 2000. In 2019, F declined to 0.118, which included F from commercial (0.090) and recreational (0.028) catches. In 2019, the ratio of F:FMSY was 0.96. Recruitment has been variable over the time-series and uncertainties around recruitment remain high throughout. Recruitment is estimated to have improved in recent years, and the lowest values in the time series occurred in 2009.

ICES advises that when the EU multiannual plan (MAP) for Western Waters and adjacent waters is applied, catches in 2021 that correspond to the F ranges in the MAP are between 2,966 tonnes and 3,770 tonnes. According to the MAP, catches higher than those corresponding to FMSY (3,108 tonnes) can only be taken under conditions specified in the MAP, whilst the entire range is considered precautionary when applying the ICES advice rule. The advised catch for 2021 is increased compared to the 2020 advice, owing to improved recruitment in recent years, an increase in the forecast SSB and the advice for 2021 being provided based on the unreduced FMSY.

For recreational removals the fishing pressure estimate is based on French data from 2010. This was rescaled in 2012 and 2017 following changes in management rules. Improved information on recreational removals would improve the quality of the assessment and advice.

There are no scientific surveys available to provide recruitment information from the Bay of Biscay. Recruitment estimates from the model are, therefore, uncertain; indices are needed to address this data gap. A pilot survey, was conducted by France in the Bay of Biscay in 2016-2019. ICES recommends that this survey be continued in order to develop a time-series.

Stock identity remains poorly understood, and tagging and genetics studies are ongoing. There are four assumed sea bass stocks: Northern (Divisions 4b-c, 7a, 7d-h); Southern Ireland and Western Scotland (Divisions 6a, 7b and 7j); Biscay (Divisions 8a-b); Portugal & Northern Spain (Divisions 8c, 9a). Stock identity has not been changed, but research on population structure are under progress.

Management

Criterion score: 0.5 info

There are management measures in place, which are partly effective in managing the stock.

The EU multiannual plan (MAP) for stocks in the Western Waters and adjacent waters applies to this stock. The plan specifies conditions for setting fishing opportunities depending on stock status and making use of the FMSY range for the stock. It aims to ensure that stocks, in particular seabass stocks, are exploited sustainably and that the decisions on fishing opportunities are based on the most up-to-date scientific information. ICES considers that the FMSY range for this stock used in the MAP as precautionary.

Seabass are not subject to EU TACs (Total Allowable Catch) and quotas. In 2015, landings exceeded advice by 23%, since then landings have been in line with or marginally under catch advice, ranging between 88% and 102% of advice (2016-2019). A total fishing closure in the Bay of Biscay took place on 28 December 2019 due to the overall annual ceiling for 2019 being deemed to be exhausted.

A high increase in the French landings for the nets fishery is observed from 2011. Indeed, as seabass is currently a non-TAC species, there is potential for displacement of fishing effort from other species with limiting quotas as observed with netters in Bay of Biscay reporting their catches from sole to seabass. With no effective limits to control the fishery, there can be risks to increase landings as observed in 2014.

Under EU regulation, the Minimum Landings Size (MLS) of sea bass in the Northeast Atlantic, is 36 cm total length (EC regulation 850/98), 40cm for French vessels in the Bay of Biscay, and 42 cm for recreational catch as of 2020. However, in the Bay of Biscay the size at which 50% of females mature is just over 42 cm (ranging between 41.31 cm and 43.08 cm). Therefore, seabass are being caught before they have had chance to reproduce.

Discards which were considered negligible previously are now estimated to account for 4.2%.

A variety of national restrictions on commercial seabass fishing are in place. These include: an historical landings limit of 5 tonnes/boat/week for French and UK trawlers landing seabass (not based on biological reference points); and a voluntary closed season from February to mid-March for longline and handline seabass fisheries in Brittany, France.

Since 2012, a national professional quota system for seabass fishing licences, defined and implemented by the Committees for Maritime Fisheries and Fish Farming, has regulated French professional catches of the species, both for the Bay of Biscay (Divisions 8a-b, 8d) and the Northern stocks (Divisions 4b-c, 7a and 7d-h). In 2017, the framework for seabass fishing activities in the Bay of Biscay was supplemented by the French introduction of a specific national administrative scheme for the management of commercial fisheries, aimed at limiting both fishing effort and capacity of the commercial fishery, at levels compatible with the ICES recommendations. These concern annual and periodic limitations of fishing opportunities, at the level of both the fishery and individual vessels. Since then, various measures have been applied to French vessels in the area: Fixing the minimum fishing size for seabass at 38 cm (French commercial vessels only) then to 40 cm since February 2020; Overall annual limit on landed catches in the Bay of Biscay, which is re-assessed each year in line with ICES recommendations on fishing opportunities for this stock; Implementation of production monitoring throughout the year (monthly during spring and summer, and biweekly during winter and autumn) which can be reinforced if necessary.

In 2018, the professional system was overhauled and replaced by a more restrictive licensing system, governing seabass fishing in the Bay of Biscay. Strengthened in 2019 and again in 2020, this latest national licensing system aims to limit effort and adjust fishing capacity by taking into account, the wide diversity of fishing practices and strategies and, the administrative measures governing the fishery, in particular the annual overall limit on authorised catches. It shall apply to all French professional fishing vessels operating in the Bay of Biscay. Since 2019, this annual scheme provides for the following measures: The requirement to hold a licence to fish seabass in the area beyond a certain quantity. This licence is divided into two categories (“Targeted fishing” and “Bycatch”). It is subjected to quotas by metier and by category; The fixing of individual seabass catch limits for both licence and non-license holders. These limits are either on an annual or monthly basis, at different levels according to the fishing method(s) and, where applicable, according to the category of licence; The contribution to the monitoring of the individual production of licensed vessels.

Since 2019, under the administrative arrangements, French vessels, by each production unit under the occupational scheme were subject to an individual annual catch limit. In addition, the following specific limits have been added: in October and November, an individual limit of 50 Kg of seabass per vessel and per trip, up to a maximum of 50 Kg per day; in December, an individual limit of 250 Kg of seabass per vessel per trip, except for vessels holding a seabass licence for pelagic trawling as “Targeted fishing”.

A series of management measures have also been implemented for the French recreational fishery, including, a MLS of 42 cm which has been implemented since 2013 (French association of anglers) and recreational removals were reduced to a two fish-bag limit in 2020.

The importance of seabass to recreational fisheries, artisanal and other inshore commercial fisheries and large-scale offshore fisheries in different regions indicates that resource sharing is an important issue for management consideration.


The UK is due to leave the EU on 31st December 2020, and new UK Fisheries legislation is being developed during 2020. MCS will update ratings with new management information when new legislation comes into force.

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

Seabass are caught by a variety of methods (i.e. nets, lines, bottom trawl, pelagic trawl, Danish seine and purse seine) in the north and central Bay of Biscay.

Seabass (Dicentrarchus labrax), are caught by commercial and recreational fishers. There is significant recreational fishing for seabass in inshore waters, and many small-scale artisanal fisheries, especially line fishing. These fisheries have developed a high seasonal dependency on seabass. Approximately 22% of the total estimated catch in this fishery is from recreational fishing and 78% from commercial fishing, based on 2020 catch forecasting (not dissimilar to recent preceding years). In 2018, commercial catch was split between the following capture methods as follows: nets 36%; lines 23%; bottom trawl 23%; pelagic trawl 8%; Danish seine 3.7%; purse seine 1.28%; and others gears 0.51%. Most commercial seabass catches are taken in targeted fisheries, although some are caught as bycatch in other fisheries. Seabass in the Bay of Biscay is mainly targeted by France with more than 95.6% of the international landings in 2019, Spain was responsible for the rest (4.4%).

For France, line fisheries (handlines and longlines) take place all year round (especially in quarters 3 and 4), while nets, pelagic and bottom trawl fisheries take place November-April, the period when pre-spawning and spawning seabass aggregate to reproduce. Fisheries targeting offshore aggregation are mainly netters and, to a lesser extent, pelagic trawlers which operate December-March. In 2019, an increase was observed for liners and other gears, and a decrease for netters, pelagic trawlers and bottom trawlers. Netters are very dependent on weather conditions.

Demersal otter trawls use doors to hold nets open that penetrate the seabed, resulting in the abrasion of habitat features, and smothering in soft sediment areas, within this ecoregion. Bycatches of non-target species can make up a high proportion of catch weight in demersal otter trawls and can take bycatches of protected, endangered and threatened species in certain circumstances. The common skate, and less often spurdogs, are caught as bycatch in demersal trawl fisheries within the Bay of Biscay and Iberian waters.

In autumn and winter, seabass seems to primarily target small pelagic fish. most notably mackerel (Scomber scombrus), scads (Trachurus spp.), anchovy (Engraulis encrasicolus), and sardine (Sardina pilchardus). These four species also dominate the diets of common dolphins. This overlap in feeding preferences is thought to increase the risk of dolphins being caught by pelagic trawls while feeding among sea bass, and may be an underlying mechanism to explain the high rate of common dolphin bycatch observed in the pelagic trawl fishery for seabass in the Bay of Biscay.

The behaviour of seabass, forming predictable aggregations for spawning in winter and moving inshore to feed at other times of the year increase the stock vulnerability to exploitation by offshore and inshore fisheries. The effects of targeting offshore spawning aggregations of seabass are poorly understood, particularly how the fishing effort is distributed in relation to the mixing of fish from different nursery grounds or summer feeding grounds, given the strong site fidelity of seabass.

Seabass is a widely distributed species in northeast Atlantic shelf waters with a range from southern Norway, through the North Sea, the Irish Sea, the Bay of Biscay, the Mediterranean and the Black Sea to North-west Africa. The species is at the northern limits of its range around the British Isles and southern Scandinavia. Warm conditions facilitate northward migration of seabass in the Northeast Atlantic, and enhance the growth and survival of young fish in estuarine and other coastal nursery habitats.

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.

Basa, Tra, Catfish or Vietnamese River Cobbler
Cod, Atlantic Cod
Cod, Pacific Cod
Coley, Saithe
Haddock
Hake, European
Monkfish, Anglerfish, White
Pollock, Alaska, Walleye
Sturgeon (Farmed)
Tilapia

References

Dars, C., Dabin, W., Demaret, F., Doremus, G., Meheust, E., Mendez-Fernandez, P., Peltier, H., Spitz, J. and Van Canneyt, O. (2017). Les echouages de mammiferes marins sur le littoral francais en 2017. Reseau National Echouages (RNE), Rapport annuel. Available at http://www.observatoire-pelagis.cnrs.fr/IMG/pdf/rapportechouages2017.pdf [Accessed on 23.07.2020]

ICES (2019). Bay of Biscay and the Iberian Coast ecoregion – Ecosystem overview. Available at http://ices.dk/sites/pub/Publication%20Reports/Advice/2019/2019/EcosystemOverview_BayofBiscayandIberianWaters_2019.pdf [Accessed 23.07.2020]

EU (2019). Regulation (EU) 2019/472 of the European Parliament and of the Council of 19 March 2019 establishing a multiannual plan for stocks fished in the Western Waters and adjacent waters, and for fisheries exploiting those stocks, amending Regulations (EU) 2016/1139 and (EU) 2018/973, and repealing Council Regulations (EC) No 811/2004, (EC) No 2166/2005, (EC) No 388/2006, (EC) No 509/2007 and (EC) No 1300/2008. Official Journal of the European Union, L 83. 17 pp. Available at http://data.europa.eu/eli/reg/2019/472/oj [Accessed 22.07.2020]

EU (2020). Council Regulation (EU) 2020/123 of 27 January 2020 fixing for 2020 the fishing opportunities for certain fish stocks and groups of fish stocks, applicable in Union waters and, for Union fishing vessels, in certain non-Union waters, ST/15319/2019/INIT, OJ L 25, 30.1.2020, p. 1–156. Available at https://eur-lex.europa.eu/eli/reg/2020/123/oj [Accessed 24.07.2020]

Froese, R. and Luna, S. (2020). European seabass, Dicentrarchus labrax. Available at https://www.fishbase.se/summary/dicentrarchus-labrax.html [Accessed 24.07.2020]

ICES (2020). Sea bass (Dicentrarchus labrax) in divisions 8.a–b (northern and central Bay of Biscay). In Report of the ICES Advisory Committee, 2020. ICES Advice 2020, bss.27.8ab. https://doi.org/10.17895/ices.advice.5938. Available at http://ices.dk/sites/pub/Publication%20Reports/Advice/2020/2020/bss.27.8ab.pdf [Accessed 22.07.2020]

ICES (2020). Working Group for the Bay of Biscay and the Iberian Waters Ecoregion (WGBIE). ICES Scientific Reports. 2:49. http://doi.org/10.17895/ices.pub.6033. Available at http://www.ices.dk/sites/pub/Publication%20Reports/Expert%20Group%20Report/Fisheries%20Resources%20Steering%20Group/2020/WGBIE_2020.pdf [Accessed 22.07.2020]

Peltier, H., Authier, M., Deaville, R., Dabin, W., Jepson, P. D., van Canneyt, O., Daniel, P. and Ridoux, V. (2016). Small cetacean bycatch as estimated from stranding schemes: The common dolphin case in the northeast Atlantic. Environmental Science and Policy, 63: 7-18. doi: 10.1016/j.envsci.2016.05.004. Available at https://www.sciencedirect.com/science/article/abs/pii/S1462901116301514 [Accessed 23.07.2020]

Peltier H., Authier M., Caurant F., Dabin W., Dars C., Demaret F., Meheust E., Ridoux V., Van Canneyt, O. and Spitz, J. (2019). Etat des connaissances sur les captures accidentelles de dauphins communs dans le golfe de Gascogne – Synthèse 2019. Rapport scientifique dans le cadre de la convention avec le MTES. Observatoire PELAGIS – UMS 3462, La Rochelle Université / CNRS, 23 pages. Available at https://www.observatoire-pelagis.cnrs.fr/IMG/pdf/Rapports/ByCatch_Rapport_CAPECET_DEB_2019.pdf [Accessed 18.09.2020]

WKBASS and IBPBass (2018). Stock Annex: Sea bass (Dicentrarchus labrax) in division 8ab (Bay of Biscay). Available at http://www.ices.dk/sites/pub/Publication%20Reports/Stock%20Annexes/2018/bss.27.8ab_SA.pdf [Accessed 22.07.2020]