Swordfish

Xiphias gladius

Method of production — Caught at sea
Capture method — Longline
Capture area — Mediterranean (FAO 37)
Stock area — Mediterranean
Stock detail — All Areas
Picture of Swordfish

Sustainability rating five info

Sustainability overview

The last assessment for swordfish in the Mediterranean was carried out in 2016 and indicated that the whilst the biomass has remained stable over the last 20years, it is badly overfished and still being subject to overfishing. Catches need to be further reduced in order to recover the stock. A 15 year recovery plan is due to commence in 2017 with the goal of achieving BMSY with at least 60% probability, but there is concern that this plan is too gradual. There are still a number of countries in the region not reporting catches which poses problems for stock assessment.

Pelagic longlining is also associated with the bycatch of vulnerable species, including sharks, sea turtles and seabirds. There are a range of mitigation measures that can be employed such as tori lines, weighted baits, circle hooks, subsurface deployment and night deployment of gear. ICCAT require two such measures to be employed, yet monitoring and reporting is generally deficient.

Biology

Swordfish is the only member of the family Xiphiidae. It is a highly migratory species, moving towards temperate or cold waters in summer to feed and returning to warmer waters to spawn. They are apex predators that feed opportunistically. Squids and fishes are major prey items. In the Atlantic, spawning takes place in spring in the southern Sargasso Sea. In the Pacific, spawning occurs during spring and summer, and in the Mediterranean between June-August. Usually solitary, it forms large schools during spawning. A fast growing fish, swordfish begin to mature at two years of age, when they are about 150 to 170 cm in length, and by age four all are mature. They can attain a maximum size of 4.5m and a weight of 650kg. Swordfish tolerate temperatures of about 5 to 27C, but their optimum range is about 18 to 22C, and larvae have been found only at temperatures exceeding 24C.

Stock information

Stock Area

Mediterranean

Stock information

Swordfish fisheries in the Mediterranean are assessed by the International Commission for the Conservation of Atlantic Tunas (ICCAT). Swordfish stocks were significantly overfished in the 1980s. In the last 15 years annual catch levels have fluctuated between 12,000-16,000 t. As reported for other species in the Mediterranean, these levels are relatively high and similar to those of bigger areas such as the North Atlantic. This could be related to higher recruitment levels in the Mediterranean than in the North Atlantic, different reproduction strategies (larger spawning areas in relation to the area of distribution of the stock) and the lower abundance of large pelagic predators (e.g. sharks) in the Mediterranean. Catches in recent years have decreased to approximately 10,000t a year and have been the lowest on record. It is thought that changes to key fishing methods and the new regulations are mostly responsible for these reductions. The latest assessment carried out in 2016 indicates that whilst the stock has remained relatively stable over the last 20 years, it is significantly overfished (Biomass, B, at 0.12Bmsy) and is subject to significant overfishing (Fishing mortality, F, 1.85Fmsy). Catches need to be further reduced in order to recover the stock.

Large catches of small swordfish, many of which have never spawned, and the low number of large individuals in the catch are cause for concern in these fisheries and has reduced the Maximum Sustainable Yield (MSY) that could be achieved.

Management

Swordfish stocks range across and are accessed by numerous coastal states, making harmonised and effective management of these individual stocks very difficult. To try and achieve this, Intergovernmental Regional Fisheries Management Organisations (RFMOs) have been established. There are five main tuna RFMOs worldwide and it is their responsibility to carry out data collection, scientific monitoring and management of these fisheries. Whilst the RFMOs are responsible for the development of management and conservation measures, the degree to which they are implemented, monitored and enforced still varies significantly between coastal states. For this reason, it is important to choose tuna that has been caught by vessels that are well regulated by their flag state. The ICCAT scientific committee recognised that there may be additional fleets taking swordfish in the Mediterranean, for example, Egypt, Israel, Lebanon, Monaco, and Syria, but the data are not reported to ICCAT or FAO.

Recent decreases in catches may be a result of improved regulation and temporal closures to the fishery, yet large catches of small swordfish, many of which have never spawned, and the low number of large individuals in the Mediterranean catch is cause for concern in these fisheries. Regulations have included fishery closures, minimum landing size regulations, a list of authorized vessels, driftnet bans and specifications on the technical characteristics of the longline gear. Several countries have also adopted additional fishery restrictions at the national level. Reported catches of juvenile swordfish of less than 90 cm have decreased on average 54% in the last two years compared with the levels of the decade of 2000s. However, these regulations appear to be insufficient in bringing the stock back to high enough levels, or reducing juvenile catches sufficiently.

A 15 year Recovery plan will start in 2017 and continuing through 2031, with the goal of achieving BMSY with at least 60% probability. Key measures include:

The introduction of a Total Allowable Catch (TAC) in 2017 of 10,500 t, reducing by 3% per year between 2018 and 2022. There are concerns that this TAC is too high and the reductions too gradual.

Introduction of a limit per country on the number of fishing vessels authorised to fish for Mediterranean swordfish to 2013-2016 average numbers.

Continuation of a 3 month fishery closure

An increase in: minimum landing / retention size from 90 to 100 cm (Lower Jaw to Fork Length (LJFL)); minimum landing / retention weight from 10 kg (round) / 7.5 kg (gilled and gutted) to 11.4 kg (round) and 10.2 kg (gilled and gutted)

Continuation of a list of authorized vessels with permits to access the various fisheries, and the introduction of a list of ports where swordfish can be landed - maintained and submitted to ICCAT.

Introduction of a list of authorised sport/fishing vessels - 'rod and line' only, allowed a maximum of 1 swordfish per vessel per day.

Commercial gear restrictions include a maximum number of hooks (2,500), minimum height (7 cm), and maximum pelagic longline length (30 NM (55 km)).

Vessels over 15m must communicate weekly information, including the date, time, location and the weight and number of Mediterranean swordfish taken in the plan area.

In addition, ICCAT have developed an IUU vessel register and a register of vessels authorised to undertake transhipments at sea. Transhipments at sea of Mediterranean swordfish are prohibited.

ICCAT has noted that the current mandatory level of observer coverage of 5% has not been implemented by many of the fleets and in 2016, updated their recommendation for a minimum of 5% observer coverage of fishing effort in each of the pelagic longline, purse seine, bait boat, traps, gillnet and trawl fisheries.

Capture Information

The biggest producers of swordfish in the Mediterranean Sea in recent years (2003-2015) have been Italy (45%), Morocco (14%), Spain (13%), Greece (10%) and Tunisia (7%). The main fishing gears used in the fishery during this time have been longlines (on average, representing 84% of the annual catch) and gillnets. While drifting gillnets have been for the most part eliminated following an EU ban in 2002 and ICCAT recommendations in 2012, some fisheries are still known to employ them either illegally or through loopholes in the regulation. Minor catches are also reported from harpoon, trap and fisheries targeting other large pelagic species (e.g. albacore).

A number of management measures are in place, including fishery closures, minimum landing size regulations, authorized vessels lists, and gear restrictions. Several countries have also adopted additional fishery restrictions at the national level. The surface longline gear in several Italian and Spanish swordfish fleets has been partially replaced by deeper set (mesopelagic) longline gear. Reported catches have decreased significantly, with average catches of juvenile swordfish (less than 90 cm) from the last two years decreasing by 54% compared with the levels in the 2000s. However, fish less than three years old usually represent 50-70% of the total yearly catches in terms of numbers (only 25-30% in weight). These large catches of small swordfish, many of which have never spawned, and the low number of large individuals in the catch are cause for concern.

Pelagic longlining is also associated with the bycatch of vulnerable species, including sharks, sea turtles and seabirds. There are a range of measures that are available and required to be employed to reduce bycatch and mortality of these species including: circle and/or barbless hooks to prevent turtle capture, and chemical, magnetic and rare earth metal shark deterrents. While longline vessels in the Atlantic must use night setting, bird-scaring lines and / or line weighting, in the Mediterranean, seabird mitigation measures are voluntary. There is also a prohibition to retain at risk shark species including: bigeye thresher, oceanic whitetip, hammerhead, silky and Porbeagle sharks. This has been in place for over four years, yet ICCAT has not received records of compliance from the majority of member states. Porbeagle is significantly overfished, and whilst there is a zero EU TAC for Porbeagle, it is still caught incidentally and discarded, and also landed by other fleets. In 2016 additional measures for blue shark were introduced, mainly focussed on improved data recording, with potential to introduce Harvest Control Rules. Monitoring of bycatch is deficient in these fisheries and the scientific committee strongly recommends improvements in data collection.

In 2016, work was begun to improve ICCAT's understanding of the trophic ecology of pelagic ecosystems that are important and unique for species managed in this area. ICCAT also introduced a number of recommendations, to improve compliance and reporting. ICCAT has noted that the current mandatory level of observer coverage of 5% has not been implemented by many of the fleets and in 2016, updated their recommendation for a minimum of 5% observer coverage of fishing effort in each of the pelagic longline, purse seine, bait boat, traps, gillnet and trawl fisheries.

References

Froese, R. and D. Pauly. Editors. 2016. FishBase. Available at www.fishbase.org [Accessed Dec 2016].

ICCAT, 2016. Resolutions, recommendations and other decisions. Available at https://www.iccat.int/en/RecsRegs.asp [Accessed Dec 2016].

ICCAT, 2016. Report of the standing committee on research and statistics. Madrid, Spain 3 to 7, October 2016. Available at https://www.iccat.int/Documents/Meetings/Docs/2016_SCRS_ENG.pdf [Accessed Nov 2016].

ISSF, 2016. Status of the world fisheries for tuna: Management of tuna stocks and fisheries, 2016. ISSF Technical Report 2016-14.International Seafood Sustainability Foundation, Washington, D.C., USA. Available at http://iss-foundation.org/downloads/13305/ [Accessed Nov 2016].