Last updated on 18 February 2016

SUMMARY

SUMMARY

IDENTIFICATION

SCIENTIFIC NAME(s)

Katsuwonus pelamis

SPECIES NAME(s)

Skipjack tuna

There remains uncertainty around the stock structure of skipjack in the Atlantic but the hypothesis of separate Eastern and Western stocks is the most plausible (ICCAT, 2006).


ANALYSIS

Strengths

The population of skipjack tuna in the western Atlantic is most likely healthy and fishing mortality rates are sustainable. Catches have been below maximum sustainable levels. The fishing effort of the Brazilian baitboat fishery, the primary fishery for skipjack in the region, has remained stable over the past 20 years. The International Commission for the Conservation of Atlantic Tunas manages skipjack tuna in the western Atlantic.

Weaknesses

There are no formally adopted target or limit reference points and although the framework exists, no harvest control rule. No management measures are in place, including an absence of catch limits. Information on bycatch interactions is limited.

FISHSOURCE SCORES

Management Quality:

Management Strategy:

≥ 6

Managers Compliance:

≥ 6

Fishers Compliance:

≥ 6

Stock Health:

Current
Health:

9.2

Future Health:

9.2


RECOMMENDATIONS

CATCHERS & REGULATORS

1. Ensure member countries comply with all conservation and management measures (CMMs) of the International Commission for the Conservation of Atlantic Tunas (ICCAT), including measures aimed at both target and bycatch species, and all other mandated obligations. Member countries must make information on monitoring and compliance with all ICCAT obligations publicly available, including actions being taken to address any identified non-compliance with ICCAT CMM’s.
2. Promote the adoption by the ICCAT and member countries of precautionary management measures, including target and limit biological reference points, harvest control rules, increased observer coverage for all fisheries, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met.
3. Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. The Scientific Committee specifically noted that countries should improve logbook and sampling forms. Countries should maintain catches below the maximum sustainable level (MSY), as suggested by the Scientific Committee.
4. Conduct studies, increase monitoring and publish information to assess purse seine interactions with protected, endangered and threatened (PET) and other bycatch species. Conduct studies on the ecosystem impacts of fish aggregating devices (FADs). Identify and mandate best practices bycatch mitigation techniques. Demand compliance with ICCAT management measures prohibiting the retention of oceanic whitetip, silky, thresher and hammerhead sharks.

RETAILERS & SUPPLY CHAIN

1. Encourage the International Commission for the Conservation of Atlantic Tunas (ICCAT) and individual member countries to adopt precautionary and ecosystem-based management measures. Demand that member countries comply with all ICCATs Conservation and Management Measures.
2. Explore implementation of control documents to ensure supplier compliance with ICCAT conservation and management measures (CMMs) (e.g. around bycatch). Source from vessels registered on the International Seafood Sustainability Foundation (ISSF) Proactive Vessel Register (PVR). Encourage ISSF to fully implement PVR resolutions, and to expand the PVR list to include all relevant gear types.
3. Encourage the ICCAT and member countries to conduct studies, increase monitoring and publish information to assess purse seine interactions with protected, endangered and threatened (PET) and other bycatch species. Explore opportunities to support studies and data gathering.
4. Contact SFP to learn more about fishery improvement projects (FIPs) and SFP’s Supplier Roundtables.


FIPS

  • Atlantic Ocean tropical tuna - purse seine (OPAGAC):

    Stage 4, Progress Rating A

CERTIFICATIONS

No related MSC fisheries

Fisheries

Within FishSource, the term "fishery" is used to indicate each unique combination of a flag country with a fishing gear, operating within a particular management unit, upon a resource. That resource may have a known biological stock structure and/or may be assessed at another level for practical or jurisdictional reasons. A fishery is the finest scale of resolution captured in FishSource profiles, as it is generally the scale at which sustainability can most fairly and practically be evaluated.

ASSESSMENT UNIT MANAGEMENT UNIT FLAG COUNTRY FISHING GEAR
Western Atlantic Ocean Antigua Barbuda Antigua and Barbuda Associated purse seining
Unassociated purse seining
ICCAT Brazil Pole-lines hand operated
Curaçao Associated purse seining
Panama Associated purse seining
Spain Purse seines
Unassociated purse seining

Analysis

OVERVIEW

Last updated on 9 January 2015

Strengths

The population of skipjack tuna in the western Atlantic is most likely healthy and fishing mortality rates are sustainable. Catches have been below maximum sustainable levels. The fishing effort of the Brazilian baitboat fishery, the primary fishery for skipjack in the region, has remained stable over the past 20 years. The International Commission for the Conservation of Atlantic Tunas manages skipjack tuna in the western Atlantic.

Weaknesses

There are no formally adopted target or limit reference points and although the framework exists, no harvest control rule. No management measures are in place, including an absence of catch limits. Information on bycatch interactions is limited.

RECOMMENDATIONS

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure member countries comply with all conservation and management measures (CMMs) of the International Commission for the Conservation of Atlantic Tunas (ICCAT), including measures aimed at both target and bycatch species, and all other mandated obligations. Member countries must make information on monitoring and compliance with all ICCAT obligations publicly available, including actions being taken to address any identified non-compliance with ICCAT CMM’s.
2. Promote the adoption by the ICCAT and member countries of precautionary management measures, including target and limit biological reference points, harvest control rules, increased observer coverage for all fisheries, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met.
3. Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. The Scientific Committee specifically noted that countries should improve logbook and sampling forms. Countries should maintain catches below the maximum sustainable level (MSY), as suggested by the Scientific Committee.
4. Conduct studies, increase monitoring and publish information to assess purse seine interactions with protected, endangered and threatened (PET) and other bycatch species. Conduct studies on the ecosystem impacts of fish aggregating devices (FADs). Identify and mandate best practices bycatch mitigation techniques. Demand compliance with ICCAT management measures prohibiting the retention of oceanic whitetip, silky, thresher and hammerhead sharks.

Recommendations to Retailers & Supply Chain

1. Encourage the International Commission for the Conservation of Atlantic Tunas (ICCAT) and individual member countries to adopt precautionary and ecosystem-based management measures. Demand that member countries comply with all ICCATs Conservation and Management Measures.
2. Explore implementation of control documents to ensure supplier compliance with ICCAT conservation and management measures (CMMs) (e.g. around bycatch). Source from vessels registered on the International Seafood Sustainability Foundation (ISSF) Proactive Vessel Register (PVR). Encourage ISSF to fully implement PVR resolutions, and to expand the PVR list to include all relevant gear types.
3. Encourage the ICCAT and member countries to conduct studies, increase monitoring and publish information to assess purse seine interactions with protected, endangered and threatened (PET) and other bycatch species. Explore opportunities to support studies and data gathering.
4. Contact SFP to learn more about fishery improvement projects (FIPs) and SFP’s Supplier Roundtables.

1.STOCK STATUS

STOCK ASSESSMENT

Last updated on 13 January 2015

The stock was last assessed in 2014 and included catch and effort data from 1952 through 2013. Stock assessment of skipjack is a challenge as it spawns continuously during the year, growth varies by area and cohorts cannot be identified (ICCAT, 2012a). Four models were used for this assessment: A mean length based mortality estimator,a catch-only model, a Bayesian surplus production model and a Stock Production Model Incorporating Covariates (ASPIC) (ICCAT, 2014b).

SCIENTIFIC ADVICE

Last updated on 13 January 2015

No specific management recommendations have been provided other than keeping catches below maximum sustainable levels (MSY) (ICCAT 2014b).

Reference Points

Last updated on 13 Jan 2015

Parameter Value
Fcurrent/FMSY ~0.7
Bcurrent/BMSY ~1.3
MSY 30,000-32,000 mt
CURRENT STATUS

Last updated on 13 January 2015

The stock was determined to most likely not be overfished (B2013/BMSY>1) or undergoing overfishing (F2013/FMSY<1). Catches in 2013 (17,996 tons) were well below the estimated maximum sustainable yield estimates (30,000-32,000 tons) (ICCAT, 2014a).

Trends

Last updated on 13 Jan 2015

Abundance indices from fisheries operating in the western Atlantic (Brazilian baitboat, Venezuelan purse seine and US longline) have been variable with a slight increase over time. Catches of skipjack tuna in this region reached close to historically high levels in 2011 (32,383 t) and 2012 (32,846 t) but decreased significantly during 2013 (17,996 t) (ICCAT 2014a).

2.MANAGEMENT QUALITY

MANAGEMENT

Last updated on 13 January 2015

No specific management measures are in effect for the stock (ICCAT, 2014a).

Recovery Plans

Last updated on 13 Jan 2015

There is no recovery plan in place but skipjack tuna populations appear to be healthy.

COMPLIANCE

Last updated on 9 December 2009

There are no specific management measures for skipjack tuna so no information on compliance is available.

Brazil
Pole-lines hand operated

Last updated on 17 March 2013

A national on-board observers program is in operation and Vessel Monitoring Systems are mandatory for certain classes of vessels (ICCAT, 2012b). Logbooks are mandatory for the skipjack pole-and-line fishery (Interministerial Rule No. 26, 2005).

3.ENVIRONMENT AND BIODIVERSITY

BYCATCH
ETP Species

Last updated on 13 January 2015

Bycatch of sea turtles can occur in purse seine and longline fisheries. In the Atlantic Ocean, green, hawksbill, leatherback, loggerhead and olive ridley sea turtles have the potential to be incidentally captured in these fisheries. Green, leatherback, and loggerhead sea turtles have been classified as Endangered by the International Union for the Conservation of Nature (IUCN), hawksbill as Critically Endangered and olive Ridley as Vulnerable (Seminoff 2004)(Mortimer and Donnelly 2008)(TEWG 2007)(MTSG 2006)(Abreu-Grobis and Plotkin 2008). Purse seines are prohibited from setting around sea turtles and any incidentally captured sea turtles (purse seine or longline cpatured) must be released using safe handling techniques (ICCAT 2010a).Several species of sharks, silky, oceanic whitetip and hammerhead sharks are prohibited from being retained if incidentally captured {ICCAT 2011}{ICCAT 2010b}{ICCAT 2010c}.

Brazil
Pole-lines hand operated

Last updated on 18 March 2013

Pole and line fisheries using live bait are mentioned in the Brazilian National Plan of Action for the Conservation of Albatrosses and Petrels as being potentially threatening to seabirds (MMA, undated). Cory’s shearwater (Calonectris diomedea: IUCN Least Concern but decreasing; BirdLife International, 2012a), Cape Verde shearwater (Calonectris edwardsii: IUCN Near Threatened; BirdLife International, 2012b) and great shearwater (Puffinus gravis: IUCN Least Concern and stable in trend; BirdLife International, 2012c) are reportedly among the birds attracted to the live bait release. A whip is reported to be often used to disperse seabirds, injuring or killing them and monitoring and education should be priorities in the fishery (Neves et al., 2007) – seabird and sea turtle bycatch monitoring and mitigation have mainly focused on longline fisheries. Although rates are not available from the fishery, in general bycatch levels in pole-and-line tuna fisheries are low, and survival rates are high as barbless hooks are used (Gilman & Lundin, 2008).

A 2011 regulation prohibits the retention on board and sale of Bigeye thresher shark Alopias superciliosus, which is classified on the IUCN Red List as Endangered in the western central Atlantic and Near Threatened in the southwest Atlantic, but is most frequently reported as bycatch in longline than pole and line fisheries (Amorim et al., 2009).

Other Species

Last updated on 13 January 2015

In Atlantic purse seine (associated) fisheries, billfish, bony fish, other tuna species and sharks can be incidentally captured. Bycatch in unassociated purse seine fisheries typically consists of fewer species and occurs in less amounts. Observer rerecords from French and Spanish purse seiners indicate that blue marlin, dolphinfish, rainbow runner, triggerfish, silky and oceanic whitetip sharks are bycatch species in associated fisheries(Amande et al. 2010). Blue marlin are currently fished at unsustainable levels (ICCAT 2011a). Bycatch in fisheries such as purse seine are considered to be a contributing factor to silky shark population declines (Bonfil 20009). The status of the other species is unknown in the Atlantic. In unassociated fisheries, Atlantic sailfish have been reported as a common bycatch species (Chassot et al. 2008). Atlantic sailfish populations in the eastern Atlantic are likely undergoing overfishing (ICCAT 2009).

Under the International Commission for the Conservation of Atlantic Tunas (ICCAT), countries are required to report bycatch and discards. In addition, several species of sharks, silky, oceanic whitetip and hammerhead, are prohibited from being retained if incidentally captured {ICCAT 2011b}{ICCAT 2010b}{ICCAT 2010c}. Management measures for other bycatch species, such as dolphinfish, wahoo, rainbow runner and triggerfish are not in place.

Brazil
Pole-lines hand operated

Last updated on 16 July 2013

Skipjack is the main target species but is caught along with juvenile yellowfin and with bigeye tunas around FADs (ICCAT, 2012a). Skipjack composes 88% of baitboat catches, and yellowfin at 4% is the second largest catch (ICCAT, 2012b). The pole and line fishery tends to catch smaller yellowfin than other gears; and an analysis found undersized yellowfin consistently exceeded the ICCAT-recommended 15% tolerance, but this recommendation was repealed in 2006 due to impracticality (Mayer & Andrade, 2008). Yellowfin was found in 2010 to be in an overfished condition (ICCAT, 2012a).

HABITAT
Brazil
Pole-lines hand operated

Last updated on 17 March 2013

There is no contact of the gear with benthic habitats so negative impacts are not to be expected.

Marine Reserves

Last updated on 17 Mar 2013

No management closures operate in the West Atlantic.

FishSource Scores

Last updated on 22 October 2018

SELECT SCORES

MANAGEMENT QUALITY

As calculated for 2013 data.

The score is ≥ 6.

There are no specific management plans in place but Score 2 AND Score 4 have been equal to or above 6 in recent years. The stock is NOT managed through

As calculated for 2013 data.

The score is ≥ 6.

Management targets are lacking and quotas are not set but the stock was determined at the last assessment not to be overfished or undergoing overfishing and catch levels have remained below MSY levels on average.

As calculated for 2013 data.

The score is ≥ 6.

No quotas are set but the stock was determined at last assessment to be not overfished or undergoing overfishing and catch levels have remained below MSY levels on average.

STOCK HEALTH:

As calculated for 2013 data.

The score is 9.2.

This measures the Ratio SSB/SSBmsy as a percentage of the SSB=SSBmsy.

The Ratio SSB/SSBmsy is 1.30 . The SSB=SSBmsy is 1.00 .

The underlying Ratio SSB/SSBmsy/SSB=SSBmsy for this index is 130%.

As calculated for 2013 data.

The score is 9.2.

This measures the Ratio F/Fmsy as a percentage of the F management target.

The Ratio F/Fmsy is 0.700 . The F management target is 1.00 .

The underlying Ratio F/Fmsy/F management target for this index is 70.0%.

To see data for biomass, please view this site on a desktop.
To see data for catch and tac, please view this site on a desktop.
To see data for fishing mortality, please view this site on a desktop.
No data available for recruitment
No data available for recruitment
To see data for management quality, please view this site on a desktop.
To see data for stock status, please view this site on a desktop.
DATA NOTES

1) The time series of F and SSB are provided relative to MSY (F/FMSY, B/BMSY); the thresholds have been set accordingly. 2) There is no harvest control rule in place so score 1 has been determined qualitatively. 3) TACs are not set so scores 2 and 3 have also been assigned qualitative scores.

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Fishery Improvement Projects (FIPs)

SELECT FIP

Access FIP Public Report

Progress Rating: A
Evaluation Start Date: 1 Sep 2016
Type: Comprehensive

Comments:

 

FIP rated A. FIP reported Stage 4 result within the  last 12 months  - verification of successful implementation and outcomes of  the code of practice  (observers on vessels) 

1.
FIP Development
Sep 15
2.
FIP Launch
Jan 16
Sep 16
3.
FIP Implementation
Jul 18
4.
Improvements in Fishing Practices and Fishery Management
Sep 17
5.
Improvements on the Water
Verifiable improvement on the water
6.
MSC certification (optional)
MSC certificate made public

Certifications

Marine Stewardship Council (MSC)

No related MSC certifications

Sources

Credits

Amande, M.J., Ariz, J., Chassot, E., de Molina, A.D., Gaerner, D., Murua, H., Pianet, R., Ruiz, J. and Chavance, P. 2010. Bycatch of the European purse seine tuna fishery in the Atlantic Ocean from 2003-2007 period. Aquatic Living Resources 23:353-362.

Chassot, E., Amande, M.J., Chavance, P. Pianet, R. and Dedo, R.G. 2008. A preliminary attempt to estimate tuna discards and bycatch in the French purse seine fishery of the eastern Atlantic Ocean. SCRS/2008/117.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2009a. Report of the 2009 sailfish stock assessment. Reciefe, Brazil, 1-5 June 2009.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2010a. Recommendation by ICCAT on the by-catch of sea turtles in ICCAT fisheries. Recommendation 10-09.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2010b. Recommendation by ICCAT on hammerhead sharks (family Sphyrnidae) caught in association with fisheries managed by ICCAT. Recommendation 10-08.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2010c. Recommendation by ICCAT on hammerhead sharks (family Sphyrnidae) caught in association with fisheries managed by ICCAT. Recommendation 10-08.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2011a. Report of the 2011 blue marlin stock assessment and white marlin data preparatory meeting. Madrid, Spain, 25-29 April 2011.

International Commission for the Conservation of Atlantic Tuna (ICCAT). 2011b. Recommendation by ICCAT on the conservation of silky sharks caught in association with ICCAT fisheries. Recommendation 11-08.

International Commission for the Conservation of Atlantic Tunas (ICCAT). 2014a. Report of the standing committee on research and statistics (SCRS). Madrid, Spain 29 September to 3 October 2014.

International Commission for the Conservation of Atlantic Tunas (ICCAT). 2014b. Report of the 2014 ICCAT east and west Atlantic skipjack stock assessment meeting. Dakar, Senegal June 23 to July 1, 2014.

References

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    Skipjack tuna - Western Atlantic Ocean

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