Summary

IDENTIFICATION

SCIENTIFIC NAME

Thunnus albacares

SPECIES NAME(S)

Yellowfin tuna

An assessment unit is considered to exist in the Indian Ocean by the Indian Ocean Tuna Commission (IOTC, 2014).


ANALYSIS

Strengths

The stock assessment has been carried out regularly using a range of assessment methods.  The IOTC has recently adopted precautionary management, which includes the use of interim target and limit reference points and calls for the use of harvest control rules and management strategy evaluation. 

Weaknesses

Yellowfin tuna in the Indian Ocean are overfished and undergoing overfishing.  Catches have been over recommended level since 2011.  Recent advice calls for a 20% reduction but only a 5-15% reduction (depending on the fleet) has been adopted by the Commission (2016). IUU fishing and piracy has been a major issue in the Indian Ocean and there are compliance issues with regard to the quality of reported data {IOTC 2013b}.  The Commission has taken recent action to continue addressing these issues but the success of these measures is not yet known. A number of bycatch species, including sharks, sea turtles and sea birds are incidentally captured in fisheries targeting yellowfin tuna.  Observer coverage rates are low in fisheries targeting yellowfin tuna.

SCORES

Management Quality:

Management Strategy:

≥ 6

Managers Compliance:

≥ 6

Fishers Compliance:

< 6

Stock Health:

Current
Health:

7.6

Future Health:

7.6


RECOMMENDATIONS

CATCHERS & REGULATORS

1. Ensure member countries comply with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by individual members and cooperating non-members publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline and purse seine fleets, and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance. Encourage IOTC and parties to comply with current required onboard observer coverage rates.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Specifically, there is concern over inaccurate reporting of catches from Pakistan’s gillnet fishery, India’s purse seine and longline fisheries and there is uncertainty surrounding the reported catches from the coastal fisheries of Sri Lanka, Indonesia, Yemen and Madagascar. Catch and effort data are also missing from the fresh-tuna longline fishery of Indonesia, Taiwan and China along with coastal fisheries from Yemen, Indonesia and Madagascar. Catch and effort data from Iran, Pakistan and Sri Lanka’s gillnet fisheries are also lacking.
4. Encourage IOTC to conduct studies, increase monitoring where needed to meet scientific recommendations and make resulting datasets available for assessments of purse seine and longline interactions with endangered, threatened and Protected (ETP) and other bycatch species. Call upon IOTC to identify and mandate best practices bycatch mitigation techniques. Comply with recently adopted IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks and those requiring member countries to adopt fish aggregating device designs that reduce entanglements of bycatch species.

RETAILERS & SUPPLY CHAIN

1. Ask the Indian Ocean Tuna Commission (IOTC) and individual member countries to adopt precautionary and ecosystem-based management measures including effective harvest strategies and to increase observer coverage in fisheries where this is needed to meet scientific recommendations.
2. Require your suppliers to source only from fisheries that comply with all IOTC Conservation and Management Measures, and request that IOTC continue to make information on compliance by members and cooperating non-members publicly available (IOTC.org). An example of how this might be achieved is a control document that ensures recording and reporting interactions, and prohibition on retaining thresher and oceanic whitetip sharks.
3. Source from vessels registered on the International Seafood Sustainability Foundation (ISSF) Proactive Vessel Register (PVR) that are in full compliance with all PVR measures relevant to their gear type as demonstrated by annual independent audit reports that are made publicly available.
4. Ask ISSF to expand the ecological sustainability criteria against which tuna vessels using gear other than purse seine on the PVR are assessed.
5. Contact SFP to learn more about fishery improvement projects (FIPs) and SFP’s Supplier Roundtables.


FIPS

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

    Stage 4, Progress Rating A

  • Indian Ocean tuna - purse seine (SIOTI):

    Stage 3, Progress Rating C

  • Indonesia/Indian Ocean tuna and large pelagics - longline:

    Stage 4, Progress Rating B

  • Indonesia pole and line tuna:

    Stage 5, Progress Rating A

  • Longline tuna and large pelagics:

    Stage 4, Progress Rating B

  • Yellowfin tuna Indonesia:

    Stage 4, Progress Rating D

CERTIFICATIONS

  • Echebastar Indian Ocean purse seine skipjack, yellowfin and bigeye tuna:

    Not certified

  • Maldives handline yellowfin tuna:

    Withdrawn

  • Maldives pole & line skipjack & yellowfin tuna:

    MSC Certified

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
Indian Ocean IOTC India Hooks and lines
Longlines
Indonesia Gillnets and entangling nets
Handlines hand operated
Hooks and lines
Longlines
Mechanized lines
Pole-lines hand operated
Purse seines
Seine nets
Unassociated purse seining
Korea, Republic of Longlines
Malaysia Handlines hand operated
Maldives Pole-lines hand operated
Mauritius Purse seines
Unassociated purse seining
Oman Handlines hand operated
Spain Longlines
Purse seines
Unassociated purse seining
Sri Lanka Drifting longlines
Thailand Handlines hand operated
Longlines
Mechanized lines

Analysis

OVERVIEW

Last updated on 22 January 2015

Strengths

The stock assessment has been carried out regularly using a range of assessment methods.  The IOTC has recently adopted precautionary management, which includes the use of interim target and limit reference points and calls for the use of harvest control rules and management strategy evaluation. 

Weaknesses

Yellowfin tuna in the Indian Ocean are overfished and undergoing overfishing.  Catches have been over recommended level since 2011.  Recent advice calls for a 20% reduction but only a 5-15% reduction (depending on the fleet) has been adopted by the Commission (2016). IUU fishing and piracy has been a major issue in the Indian Ocean and there are compliance issues with regard to the quality of reported data {IOTC 2013b}.  The Commission has taken recent action to continue addressing these issues but the success of these measures is not yet known. A number of bycatch species, including sharks, sea turtles and sea birds are incidentally captured in fisheries targeting yellowfin tuna.  Observer coverage rates are low in fisheries targeting yellowfin tuna.

RECOMMENDATIONS

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure member countries comply with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by individual members and cooperating non-members publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline and purse seine fleets, and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance. Encourage IOTC and parties to comply with current required onboard observer coverage rates.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Specifically, there is concern over inaccurate reporting of catches from Pakistan’s gillnet fishery, India’s purse seine and longline fisheries and there is uncertainty surrounding the reported catches from the coastal fisheries of Sri Lanka, Indonesia, Yemen and Madagascar. Catch and effort data are also missing from the fresh-tuna longline fishery of Indonesia, Taiwan and China along with coastal fisheries from Yemen, Indonesia and Madagascar. Catch and effort data from Iran, Pakistan and Sri Lanka’s gillnet fisheries are also lacking.
4. Encourage IOTC to conduct studies, increase monitoring where needed to meet scientific recommendations and make resulting datasets available for assessments of purse seine and longline interactions with endangered, threatened and Protected (ETP) and other bycatch species. Call upon IOTC to identify and mandate best practices bycatch mitigation techniques. Comply with recently adopted IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks and those requiring member countries to adopt fish aggregating device designs that reduce entanglements of bycatch species.

Recommendations to Retailers & Supply Chain

1. Ask the Indian Ocean Tuna Commission (IOTC) and individual member countries to adopt precautionary and ecosystem-based management measures including effective harvest strategies and to increase observer coverage in fisheries where this is needed to meet scientific recommendations.
2. Require your suppliers to source only from fisheries that comply with all IOTC Conservation and Management Measures, and request that IOTC continue to make information on compliance by members and cooperating non-members publicly available (IOTC.org). An example of how this might be achieved is a control document that ensures recording and reporting interactions, and prohibition on retaining thresher and oceanic whitetip sharks.
3. Source from vessels registered on the International Seafood Sustainability Foundation (ISSF) Proactive Vessel Register (PVR) that are in full compliance with all PVR measures relevant to their gear type as demonstrated by annual independent audit reports that are made publicly available.
4. Ask ISSF to expand the ecological sustainability criteria against which tuna vessels using gear other than purse seine on the PVR are assessed.
5. Contact SFP to learn more about fishery improvement projects (FIPs) and SFP’s Supplier Roundtables.

Indonesia
Longlines

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014).. Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.
4. Source from vessels operating within the FIP and support the FIP’s work plan implementation.

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.

Purse seines

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.

Hooks and lines

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.

Pole-lines hand operated

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014).. Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.
4. Source from vessels operating within the FIP and support the FIP’s work plan implementation.

Seine nets

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.

Mechanized lines

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Ensure Indonesia complies with all Indian Ocean Tuna Commission’s (IOTC’s) conservation and management measures (CMMs), including measures aimed at both target and incidental market and non-market species, and all other obligations. Through your delegation to IOTC, encourage the compliance committee to make information on non-compliance by Indonesia publicly available in order to increase the incentive for compliance by all IOTC members and cooperating non-members.
2. Promote the adoption by the Indian Ocean Tuna Commission (IOTC) of precautionary and ecosystem-based management measures, including formal biological reference points (interim currently in place), harvest control rules, increased observer coverage for longline fleets, national management measures and monitoring efforts adequate to ensure harvest strategy objectives are being met. Adopt domestic laws and regulation to implement IOTC measures and provide monitoring and surveillance adequate for compliance.
3. Encourage IOTC to adopt management measures that will reduce catches of yellowfin tuna to be a minimum of 80% of current levels (2014). Improve data collection and reporting to ensure complete data sets (i.e. catches, effort, size), which are needed for robust stock assessments. Conduct studies, increase monitoring and publish information to assess purse seine and longline interactions with protected, endangered and threatened (PET) and other bycatch species. Identify and mandate best practices bycatch mitigation techniques. Comply with recently implemented IOTC management measures prohibiting the retention of oceanic whitetip and thresher sharks.

Maldives

Last updated on 6 February 2017

Improvement Recommendations to Catchers & Regulators

1. Monitor fishery and management system for any changes that could jeopardize MSC re-certification.

Recommendations to Retailers & Supply Chain

1. Support the sustainability achievements of this fishery by sourcing this product, and ensure that the producers are aware that sustainability certification played a role in your decision to source this product.

Thailand

Last updated on 6 February 2017

Improvement Recommendations to Catchers & Regulators

1. Monitor fishery and management system for any changes that could jeopardize MSC re-certification.

Recommendations to Retailers & Supply Chain

1. Support the sustainability achievements of this fishery by sourcing this product, and ensure that the producers are aware that sustainability certification played a role in your decision to source this product.

1.STOCK STATUS

STOCK ASSESSMENT

Last updated on 14 December 2015

Yellowfin tuna is assumed to be a single stock across Indian Ocean. This is supported by the tag recoveries that provide evidence of large movements of yellowfin tuna. The latest full stock assessment was conducted in 2015 and an updated assessment was conducted in 2016. Three assessment models were used in the 2015 assessment were the, BBPm, SCAA and Stock Synthesis III . This stock assessment included catch data from 1950 through 2014 {IOTC 2015}. The udated 2016 assessment utilized the Biomass Dynamic MOdel (BDM) and Stock Synthesis III and included catch and effort data through 2015 (IOTC 2016).

Indonesia
Longlines

Last updated on 13 April 2010

Yellowfin tuna is assumed to be a single stock across Indian Ocean. This is supported by the tag recoveries that provide evidence of large movements of yellowfin tuna. However, some more detailed analysis of fisheries data suggests that the stock structure may be more complex. A study of stock structure using DNA was unable to detect whether there were subpopulations of yellowfin tuna in the Indian Ocean (IOTC 2008a).

At regional level (Indian Ocean), a range of assessments were presented in the Meeting of the Working Party on Tropical Tunas (WPTT) in Bangkok, 23 to 31 November, 2008, which included Multifan-CL, a Stock Synthesis 2 (SS2) model and an Age-structured Production Model (ASPM). Multifan – CL is a size-based, age- and spatially-structured population model that has the functionality to integrate the tagging data obtained from the Indian Ocean Tagging Programme. Stock Synthesis 2 (SS2) model used catch-at-length data, growth and a CPUE series to model the stock dynamics while ASPM used catch-at-age data and a CPUE series to estimate biomass trends and management-related parameters. Most of the models appear to provide similar perspectives on the status of the stocks despite their different levels of complexity and the uncertainties. In overall, all assessment results indicated that the biomass is below the MSY-based level and that the catch and harvest rates are slightly above MSY levels (IOTC 2008b).

At Indonesia level, several workshops have been conducted as attempts to assess the stock size of tuna in Indonesian waters. However, up until now, due to lack of accurate statistical data (that meet data requirements for scientific stock assessments), there is no scientific stock assessments relating to tunas and tuna-like species in Indonesia. Therefore tuna experts then came into agreement that until this point, there is no one that can estimate the reasonable stock size of Indonesian tuna. The tuna experts then agreed that the most important thing to assess the stock size of Indonesian tuna fisheries is by studying indicators to predict the condition and status of Indonesian tuna fisheries rather than trying to estimate the Indonesian tuna stock size.

Seine nets

Last updated on 13 April 2010

Yellowfin tuna is assumed to be a single stock across Indian Ocean. This is supported by the tag recoveries that provide evidence of large movements of yellowfin tuna. However, some more detailed analysis of fisheries data suggests that the stock structure may be more complex. A study of stock structure using DNA was unable to detect whether there were subpopulations of yellowfin tuna in the Indian Ocean (IOTC 2008a).

At regional level (Indian Ocean), a range of assessments were presented in the Meeting of the Working Party on Tropical Tunas (WPTT) in Bangkok, 23 to 31 November, 2008, which included Multifan-CL, a Stock Synthesis 2 (SS2) model and an Age-structured Production Model (ASPM). Multifan – CL is a size-based, age- and spatially-structured population model that has the functionality to integrate the tagging data obtained from the Indian Ocean Tagging Programme. Stock Synthesis 2 (SS2) model used catch-at-length data, growth and a CPUE series to model the stock dynamics while ASPM used catch-at-age data and a CPUE series to estimate biomass trends and management-related parameters. Most of the models appear to provide similar perspectives on the status of the stocks despite their different levels of complexity and the uncertainties. In overall, all assessment results indicated that the biomass is below the MSY-based level and that the catch and harvest rates are slightly above MSY levels (IOTC 2008b).

At Indonesia level, several workshops have been conducted as attempts to assess the stock size of tuna in Indonesian waters. However, up until now, due to lack of accurate statistical data (that meet data requirements for scientific stock assessments), there is no scientific stock assessments relating to tunas and tuna-like species in Indonesia. Therefore tuna experts then came into agreement that until this point, there is no one that can estimate the reasonable stock size of Indonesian tuna. The tuna experts then agreed that the most important thing to assess the stock size of Indonesian tuna fisheries is by studying indicators to predict the condition and status of Indonesian tuna fisheries rather than trying to estimate the Indonesian tuna stock size.

Mechanized lines

Last updated on 13 April 2010

Yellowfin tuna is assumed to be a single stock across Indian Ocean. This is supported by the tag recoveries that provide evidence of large movements of yellowfin tuna. However, some more detailed analysis of fisheries data suggests that the stock structure may be more complex. A study of stock structure using DNA was unable to detect whether there were subpopulations of yellowfin tuna in the Indian Ocean (IOTC 2008a).

At regional level (Indian Ocean), a range of assessments were presented in the Meeting of the Working Party on Tropical Tunas (WPTT) in Bangkok, 23 to 31 November, 2008, which included Multifan-CL, a Stock Synthesis 2 (SS2) model and an Age-structured Production Model (ASPM). Multifan – CL is a size-based, age- and spatially-structured population model that has the functionality to integrate the tagging data obtained from the Indian Ocean Tagging Programme. Stock Synthesis 2 (SS2) model used catch-at-length data, growth and a CPUE series to model the stock dynamics while ASPM used catch-at-age data and a CPUE series to estimate biomass trends and management-related parameters. Most of the models appear to provide similar perspectives on the status of the stocks despite their different levels of complexity and the uncertainties. In overall, all assessment results indicated that the biomass is below the MSY-based level and that the catch and harvest rates are slightly above MSY levels (IOTC 2008b).

At Indonesia level, several workshops have been conducted as attempts to assess the stock size of tuna in Indonesian waters. However, up until now, due to lack of accurate statistical data (that meet data requirements for scientific stock assessments), there is no scientific stock assessments relating to tunas and tuna-like species in Indonesia. Therefore tuna experts then came into agreement that until this point, there is no one that can estimate the reasonable stock size of Indonesian tuna. The tuna experts then agreed that the most important thing to assess the stock size of Indonesian tuna fisheries is by studying indicators to predict the condition and status of Indonesian tuna fisheries rather than trying to estimate the Indonesian tuna stock size.

Sri Lanka
Drifting longlines

Last updated on 5 December 2009

Yellowfin tuna is assumed to be a single stock across Indian Ocean. This is supported by the tag recoveries that provide evidence of large movements of yellowfin tuna. However, some more detailed analysis of fisheries data suggests that the stock structure may be more complex. A study of stock structure using DNA was unable to detect whether there were subpopulations of yellowfin tuna in the Indian Ocean (IOTC 2008a).

A range of assessments were presented in the Meeting of the Working Party on Tropical Tunas (WPTT) in Bangkok, 23 to 31 November, 2008, which included Multifan-CL, a Stock Synthesis 2 (SS2) model and an Age-structured Production Model (ASPM).Multifan – CL is a size-based, age- and spatially-structured population model that has the functionality to integrate the tagging data obtained from the Indian Ocean Tagging Programme. Stock Synthesis 2 (SS2) model used catch-at-length data, growth and a CPUE series to model the stock dynamics while ASPM used catch-at-age data and a CPUE series to estimate biomass trends and management-related parameters. Most of the models appear to provide similar perspectives on the status of the stocks despite their different levels of complexity and the uncertainties. In overall, all assessment results indicated that the biomass is below the MSY-based level and that the catch and harvest rates are slightly above MSY levels (IOTC 2008b).

Although important progress in the quality and quantity of analyses conducted, there remain uncertainties in the application of the models that prevented the SC from determining the current status of yellowfin tuna in a precise way. Nevertheless, most of the analyses conducted coincide in indicating that the stock is very close to an overfished state, or already overfished, and that the exploitation rate in recent years has exceeded the optimal level (2008a).

SCIENTIFIC ADVICE

Last updated on 15 December 2015

In 2015, it was advised that catches of yellowfin tuna should be reduced to a minimum of 80% of current (2014) catch levels to rebuild by 2024 {IOTC 2015}. An intermin rebuilding plan was adopted in 2016, but the success of this plan has yet to be evaluated. No new advice was provided in 2016 as a result of the updated assessment but did indicate there is a risk of continuing to exceed the biomass reference point if catches increase or remain at 2015 levels until 2018 (IOTC 2016).

REFERENCE POINTS

Last updated on 15 December 2015

Reference points for yellowfin tuna in the Indian Ocean Tuna commission Area: Source: IOTC (2016)
2015 catch estimate: 4307,575 tonnes
Average Catches (2011-2015): 390,185 tonnes
MSY: 422,000 tonnes
SB2015/SBMSY = 0.89 (0.79—0.99)
F2015/FMSY = 1.11 (0.86-1.36)
SB2015/SB0 = 0.29 

CURRENT STATUS

Last updated on 15 December 2015

The stock is currently overfished ((B2015<BMSY) and undergoing occurring(F2015>FMSY) (IOTC, 2016).

TRENDS

Last updated on 15 December 2015

Catch per unit effort trends have been decreasing over time for yellowfin tuna in the Indian Ocean {IOTC 2016}.

2.MANAGEMENT QUALITY

MANAGERS' DECISIONS

Last updated on 22 January 2015

The Indian Ocean Tuna Commission (IOTC) is one of five global tuna-regional fisheries management organizations. IOTC is mandated to manage tuna and tuna-like species in the Indian Ocean and adjacent seas. Its objective is to promote cooperation among its Members with a view to ensuring, through appropriate management, the conservation and optimum utilization of stocks and encouraging sustainable development of fisheries based on such stocks. Members of IOTC include Australia, Belize, China, Comoros, Eritrea, European Community, France, Guinea, India, Indonesia, Republic Islamic of Iran, Japan, Kenya, Republic of Korea, Madagascar, Malaysia, Mauritius, Sultanate of Oman, Pakistan, Philippines, Seychelles, Sierra Leone, Sri Lanka, Sudan, Tanzania, Thailand, United Kingdom, and Vanuatu. The Cooperating Non-Contracting Parties are Senegal, South Africa and Uruguay.

A proposal for adopting a catch limit for yellowfin tuna was introduced in 2009, along with proposed TACs for bigeye tuna and swordfish. The proposal was to introduce catch restrictions on yellowfin tuna (to the levels recommended by the Scientific Committee), including catch allocations for Members (on the basis of the catch figures indicated in the IOTC Scientific Committee report 2008). These proposals were submitted in response to the advice from the Scientific Committee that yellowfin tuna stocks were evaluated to be at levels near or below MSY; and recognizing the importance of applying the precautionary approach for the management of the stock in the Indian Ocean.  However, after considerable debate, no consensus was reached on a formula to distribute the allowable catches between Members, and the proposals for catch limits were dropped from further consideration at the 2009 IOTC meeting. The advice from the 2015 stock assessment called for a reduction in catches of around 20%. The Commission adopted a reduction of 10% for gillnet and longline vessels, 15% for purse seine vessels (with catches higher than 5,000 mt during 2014) and 5% for other gears {IOTC 2016b}.

Other management measures in place include: required reporting and recording of catches and effort, providing a record of active fishing vessels, limiting fishing capacity to levels from 2007.   Artificial lights and the use of aircraft and/or unmanned aerial vehicles is prohibited in the purse seine fishery {IOTC 2016b}.
 

Indonesia
Longlines

Last updated on 30 March 2015

Indonesian seas are divided into eleven Fisheries Managament Areas (FMAs), of which two FMAs, covering the seas on the west of Sumatera, south of Java until south of east Nusa Tenggara are located within the Indian Ocean Tuna Commission area. Indonesia has a total of 5,8 million km2 of marine waters; the Exclusive Economic Zone (12 – 200 miles) covers an area of 2,7 million km2 and 2,7 million km2 is territorial waters (<12 miles).

The Indonesian tuna fisheries are comprised of artisanal/traditional and small-scale fisheries. The artisanal/traditional fisheries are characterized by the use of small non-motorized and motorized boats with small outboard or inboard engines. The sizes of the boats range from 10 to 15 meters in length. The vessels’ capacity is roughly between less than 10 GT and up to 30 GT. The small scale fisheries comprise vessels greater than 30 GT of greater than 24 meters length. The main tuna species caught are yellowfin, bigeye, albacore and skipjack.

Indonesia has created a National Plan of Action for the management of tuna and there is a draft National Tuna Management Plan. The plan includes ways to improve monitoring, identifying catch limits, and aiding in enforcement and compliance measures {MMAF 2012}{MMAF 2014a}. Indonesia also has a National Plan of Action, tuna skipjack and neritic tuna in place {MMAF 2014b}. Indonesia is also a member of the Indian Ocean Tuna Commission.

No catch limits are in place for yellowfin tuna in the Indian Ocean. A proposal for adopting a catch limit for yellowfin tuna was introduced in 2009, along with proposed TACs for bigeye tuna and swordfish. The proposal was to introduce catch restrictions on yellowfin tuna (to the levels recommended by the Scientific Committee), including catch allocations for Members (on the basis of the catch figures indicated in the IOTC Scientific Committee report 2008). These proposals were submitted in response to the advice from the Scientific Committee that yellowfin tuna stocks were evaluated to be at levels near or below MSY; and recognizing the importance of applying the precautionary approach for the management of the stock in the Indian Ocean. However, after considerable debate, no consensus was reached on a formula to distribute the allowable catches between Members, and the proposals for catch limits were dropped from further consideration at the 2009 IOTC meeting.

The Indian Ocean Tuna Commission (IOTC) is one of five global tuna-regional fisheries management organizations. IOTC is mandated to manage tuna and tuna-like species in the Indian Ocean and adjacent seas. Its objective is to promote cooperation among its Members with a view to ensuring, through appropriate management, the conservation and optimum utilization of stocks and encouraging sustainable development of fisheries based on such stocks. Members of IOTC are Australia, Belize, China, Comoros, Eritrea, European Community, France, Guinea, India, Indonesia, Republic Islamic of Iran, Japan, Kenya, Republic of Korea, Madagascar, Malaysia, Mauritius, Sultanate of Oman, Pakistan, Philippines, Seychelles, Sierra Leone, Sri Lanka, Sudan, Tanzania, Thailand, United Kingdom, and Vanuatu. The Cooperating Non-Contracting Parties are Senegal, South Africa and Uruguay.

Purse seines

Last updated on 17 February 2011

In regards to Indonesian capture fisheries policy, management target of capture fisheries is defined by MSY. Management target for capture fisheries is set at level of 80% of MSY (MMAF, 2005).

Management of the tuna fisheries, as in other fisheries in Indonesia, is mainly by input controls through licensing, implementation of log book system, installment of a vessel monitoring system, and institutional strengthening. License is granted on the basis of fish stock utilization status, and a new license will not be issued when fish stock is fully or over exploited. Fishing fee is charged on the basis of resource rent. Tuna fishery protection also covered through regulation and limitation on the fishing fleets, fishing ground and fish landing. However, direct impact of protection still not found in the ground level.

Seine nets

Last updated on 19 April 2010

There is no officially set TAC. In regards to Indonesian capture fisheries policy, management target of capture fisheries is defined by MSY. Management target for capture fisheries is set at level of 80% of MSY (MMAF, 2005).Using 1997, then MSY of yellowfin tuna in Indonesia’s waters of Indian Ocean is 33,020 tonnes. In the regional fisheries management, in 2007, Indonesia has just achieved of Full Member status of both Indian Ocean Tuna Commission (IOTC).

Currently, there is also no catch limits decided for yellowfin tuna in Indian Ocean. The proposal for catch limits for yellowfin tuna was put forward in the IOTC Meeting in 2009 together with bigeye and swordfish. The proposals was to introduce catch restrictions on yellowfin tuna (to the levels recommended by the Scientific Committee), including catch allocations for Members (on the basis of the catch figures indicated in the IOTC Scientific Committee report 2008). These proposals were submitted in response to the advice from the Scientific Committee that yellowfin tuna stocks are evaluated to be at levels near or below MSY; and recognizing the importance of applying the precautionary approach for the management of the stock in the Indian Ocean. However, after considerable debate, no consensus was reached on a formula to distribute the allowable catches between Members, and the proposals for catch limits were dropped from further consideration at this Session. The Chair encouraged Members interested in proposing similar measures to engage in consultations well in advance of the next Session, so as to increase the chances of adoption (IOTC, 2009a). In total, there are 3,363 vessels under Authorized Fishing Vessels as per 03 February 2009. Indonesia contributes the biggest portion of these vessels, contributing to 26% of them or about 874 vessels, followed by Iran (22.7%), European countries (14.6%), Japan (12.2%) and Republic of Korea (5.5%) (IOTC, 2009b).

Management of the tuna fisheries, as in other fisheries in Indonesia, is mainly by input controls through licensing, implementation of log book system, installment of a vessel monitoring system, and institutional strengthening. License is granted on the basis of fish stock utilization status, and a new license will not be issued when fish stock is fully or over exploited. Fishing fee is charged on the basis of resource rent. Tuna fishery protection also covered through regulation and limitation on the fishing fleets, fishing ground and fish landing. However, direct impact of protection still not found in the ground level.

Mechanized lines

Last updated on 19 April 2010

There is no officially set TAC. In regards to Indonesian capture fisheries policy, management target of capture fisheries is defined by MSY. Management target for capture fisheries is set at level of 80% of MSY (MMAF, 2005).Using 1997, then MSY of yellowfin tuna in Indonesia’s waters of Indian Ocean is 33,020 tonnes. In the regional fisheries management, in 2007, Indonesia has just achieved of Full Member status of both Indian Ocean Tuna Commission (IOTC).

Currently, there is also no catch limits decided for yellowfin tuna in Indian Ocean. The proposal for catch limits for yellowfin tuna was put forward in the IOTC Meeting in 2009 together with bigeye and swordfish. The proposals was to introduce catch restrictions on yellowfin tuna (to the levels recommended by the Scientific Committee), including catch allocations for Members (on the basis of the catch figures indicated in the IOTC Scientific Committee report 2008). These proposals were submitted in response to the advice from the Scientific Committee that yellowfin tuna stocks are evaluated to be at levels near or below MSY; and recognizing the importance of applying the precautionary approach for the management of the stock in the Indian Ocean. However, after considerable debate, no consensus was reached on a formula to distribute the allowable catches between Members, and the proposals for catch limits were dropped from further consideration at this Session. The Chair encouraged Members interested in proposing similar measures to engage in consultations well in advance of the next Session, so as to increase the chances of adoption (IOTC, 2009a). In total, there are 3,363 vessels under Authorized Fishing Vessels as per 03 February 2009. Indonesia contributes the biggest portion of these vessels, contributing to 26% of them or about 874 vessels, followed by Iran (22.7%), European countries (14.6%), Japan (12.2%) and Republic of Korea (5.5%) (IOTC, 2009b).

Management of the tuna fisheries, as in other fisheries in Indonesia, is mainly by input controls through licensing, implementation of log book system, installment of a vessel monitoring system, and institutional strengthening. License is granted on the basis of fish stock utilization status, and a new license will not be issued when fish stock is fully or over exploited. Fishing fee is charged on the basis of resource rent. Tuna fishery protection also covered through regulation and limitation on the fishing fleets, fishing ground and fish landing. However, direct impact of protection still not found in the ground level.

Korea, Republic of
Longlines

Last updated on 21 June 2012

Korean longliners operating in the Indian Ocean had 7.5% observer coverage in 2010 (Kim et al., 2011).

All Korean longliners and carrier vessels are equipped and operate a vessel monitoring system to monitor their fleets in the Indian Ocean (Kim et al., 2011), but it remains uncertain on whether such data is shared with IOTC for monitoring compliance issues.

Maldives
Pole-lines hand operated

Last updated on 19 December 2011

National level measures:
Purse seining and gillnetiing for tuna and other species is banned.
There is a ban on shark fishing, but it has never been enforced to date.

Sri Lanka
Drifting longlines

Last updated on 3 February 2015

The Sri Lankan Exclusive Economic Zone (EEZ) covers 517,000 km2. Marine fisheries are divided into coastal (those fisheries taking place within the continental shelf and undertaken by the fishing craft in single day operations) and offshore/deep sea (those which take place outside the continental shelf and beyond extending up to the edge of the Exclusive Economic Zone and even in the high seas by multi-day boats) (MFAR 2007).

Management of Sri Lankan fisheries is conducted through the Ministry of Fisheries and Aquatic Sciences. The Fisheries and Aquatic Resources Act No 2 of 1996 is the prime code of rule for fisheries management in Sri Lanka. The significance provisions of this Act are:
- setting up a fisheries and aquatic resources advisory council;
- stipulation of the necessity and importance of preparing a plan for the management, regulation, conservation and development of fisheries and aquatic resources;
- designation of fisheries management areas;
- designation of fisheries committees;
- designation of management authorities;
- licensing of all types of marine fisheries introduced;
- inclusion of a section for aquaculture management;
- inclusion of provisions to collect information on all imported fish and fish products;
- stipulating a course of action to be followed in handling fishing disputes, and
- inclusion of more types of offences and penalties for them;

Research is conducted by the National Aquatic Resources Research and Development Agency.

Sri Lanka has a data collection and reporting system that has been advanced in recent years. The methods used to collect data include logbooks, vessel monitoring systems (VMS) and an observer program. The logbook program is already in place, while the VMS and observer programs were being tested during 2014. Observers are to be required on vessels larger than 24 ft. The logbook program became mandatory for vessels larger than 34 ft. in 2012. Sri Lanka has database in place to record logbook data. A new logbook will be implemented during 2015. Since 2012, Sri Lanka has produced catch and effort data through their port sampling program. In addition, Sri Lanka published a National Plan of Action for Illegal, Unregulated and Unreported fishing. Foreign vessels that are registered as an authorized vessel by the Indian Ocean Tuna Commission and have a valid National registration number are allowed to land fish in Sri Lanka. No transshipment is allowed in Sri Lankan ports (Hewapathirana et al. 2014).

Sri Lanka is a cooperating member of the Indian Ocean Tuna Commission and must comply with those management measures while operating in the high seas.

RECOVERY PLANS

Last updated on 20 January 2015

Yellowfin tuna are currently managed by an interim rebuilding plan (IOTC 2016).

COMPLIANCE

Last updated on 22 January 2015

There is no TAC or other output controls for yellowfin tuna in the Indian Ocean. Therefore, compliance cannot be measured. However, the IOTC Scientific Committee has repeatedly pointed out that fishing levels of yellowfin tuna stock have exceeded recommended amounts (IOTC 2013). In addition, the Compliance Committee indicated that reporting of mandatory statistics is generally poor, due to incomplete and/or poorly documented data, although an improvement was noted in 2012 {IOTC 2013b}. The lack of quality data can negatively impact stock assessments.

IUU fishing in the Indian Ocean and piracy have been major issues, which includes a range of illicit activities: fishing without permission or out of season; harvesting prohibited species; using outlawed types of fishing gear; disregarding catch quotas; or non-reporting or underreporting catch weights. Of particular concern are the western Indian Ocean and the maritime areas along the coast of eastern Africa. There, fishing vessels of various flags have taken advantage of the absence in coastal countries of strong enforcement mechanisms (FAO 2007). The Commission has regularly established a list of vessels presumed to have carried out illegal, unregulated and unreported fishing in the IOTC area. In 2013, the IOTC adopted a new resolution to make a record of vessels authorized to operation in the IOTC area of competence (IOTC 2013c). In 2016, the Commission took further steps to address IUU fishing and compliance with catch reporting and other Conservation and Management Measure requirements {IOTC 2016}.

Indonesia
Longlines

Last updated on 5 March 2013

There is no TAC or other output controls for yellowfin tuna in the Indian Ocean. Therefore, compliance cannot be measured. However, the IOTC Scientific Committee has repeatedly pointed out that fishing levels of yellowfin tuna stock have exceeded MSY in recent years. Average annual catch over 2003-2007 was 369,912 tonnes, while the MSY was 330,000 tonnes.

In addition to that, IUU fishing in the Indian Ocean has been a major issue, which includes a range of illicit activities: fishing without permission or out of season; harvesting prohibited species; using outlawed types of fishing gear; disregarding catch quotas; or non-reporting or underreporting catch weights. Of particular concern are the western Indian Ocean and the maritime areas along the coast of eastern Africa. There, fishing vessels of various flags have taken advantage of the absence in coastal countries of strong enforcement mechanisms (FAO 2007). The Commission has regularly been also establishing a list of vessels presumed to have carried out illegal, unregulated and unreported fishing in the IOTC area.

The Scientific Committee also noted the increase in unreported catches from gillnet fisheries. A large number of vessels from Iran (42%), Sri Lanka (19%) and Pakistan (7%) are reported as operating on the high seas, but that the Secretariat has not received complete data sets from the countries involved.

IOTC Resolution on a Regional Scheme on Port State Measures to Combat Illegal, Unreported and Unregulated Fishing is proposed in the Meeting in 2009 which intention to contribute to the long-term conservation and sustainable use of living marine resources, and in particular of highly migratory stocks, in the IOTC Area through strengthened, harmonized and transparent port State measures to prevent, deter and eliminate illegal, unreported and unregulated (IUU) fishing.

In order to regulate and monitor the fishing activities, the Indonesian fisheries authority has issued regulations:

1) Ministerial regulation Number 05 year 2008 on the obligation for fishing vessels above 30 GT to install a Vessel Monitoring System, and to activate the transmitter.

2) Ministerial regulation Number 18 year 2010 which requires the use of logbook for vessels above 5 GT, which has to be submitted to the port authority prior to unloading the catch. The Indonesian fisheries authority has developed 3 logbook systems, one each for longline/handline, purse-seine/pole and line and other gears.

In 2011, a research institute for tuna fisheries (RITF) was established to conduct port sampling and a scientific observer program for tuna fisheries in the Indian Ocean. The number of scientific observer involved in 2012 was 7 observers. The average days at sea /trip varied from 30 d/trip to 94 d/trip, with the average total days at sea was 67 days. The Observer Program data set is currently the most comprehensive and most reliable data available from the tuna fisheries in term of catch and effort information.

Purse seines

Last updated on 17 February 2011

Compliance of tuna fisheries in Indonesian waters can be assessed using the management target defined by MMAF for each tuna species as Total Allowable Catch set by the managers.

In 1998 and 2005, total catch of tuna exceeded the management target. In 2005, total catch of tuna in Eastern Indian Ocean reached 76 thousands t or about 2 thousands t more than its management target. Actual catches of tuna (excluding Skipjack) in Western Central Pacific Ocean also have been very close to the management target. In 2002, actual catch of tuna in this area was at level of management target (102 thousands t). However after that year, the actual catch started to decline until recently.

Seine nets

Last updated on 19 April 2010

It is not easy to assess the compliance of this fishery since there is no set TAC by the fishery managers so far. However, compliance of tuna fisheries in Indonesian waters can preliminarily be assessed by using the single management target defined by MMAF for each tuna species as TAC (Total Allowable Catch) set by the managers.

Latest data from Indonesia Statistics of Capture Fisheries (2009) shows that actual catch for yellowfin tuna in Indonesia’s part of Indian Ocean (Hindia Ocean, Western Timor Sea, Bali Strait and Sawu Sea) have been far exceeding their management targets (or presumably set TACs).

In 2004, total catch of yellowfin tuna reached 42,862 tonnes, exceeding the management target by more than 30%.

See Management target (TAC) vs Actual Catch

Mechanized lines

Last updated on 19 April 2010

It is not easy to assess the compliance of this fishery since there is no set TAC by the fishery managers so far. However, compliance of tuna fisheries in Indonesian waters can preliminarily be assessed by using the single management target defined by MMAF for each tuna species as TAC (Total Allowable Catch) set by the managers.

Latest data from Indonesia Statistics of Capture Fisheries (2009) shows that actual catch for yellowfin tuna in Indonesia’s part of Indian Ocean (Hindia Ocean, Western Timor Sea, Bali Strait and Sawu Sea) have been far exceeding their management targets (or presumably set TACs).

In 2004, total catch of yellowfin tuna reached 42,862 tonnes, exceeding the management target by more than 30%.

See Management target (TAC) vs Actual Catch

Maldives
Pole-lines hand operated

Last updated on 13 August 2009

Compliance and enforcement of foreign tuna fishing vessels operating beyond the 75 nm limit is low (Huntington et al 2010).

Sri Lanka
Drifting longlines

Last updated on 3 February 2015

Sri Lankan provides a report on compliance with Indian Ocean Tuna Commission management recommendations on an annual basis. According to the 2013 report, Sri Lanka has provided information on the majority of mandatory measures. Information on observer coverage, and the distribution of fishing catch and effort was not provided. Sri Lanka indicates that they are working towards implementing an observer program and working to refine their logbook and vessel monitoring programs. The Scientific Committee noted that there is some uncertainty surrounding reported catches of yellowfin tuna from coastal Sri Lankan fisheries. There is no total allowable catch limit for yellowfin tuna in the Indian Ocean (Hewapathirana et al. 2014)(IOTC 2014).

3.ENVIRONMENT AND BIODIVERSITY

ETP SPECIES

Last updated on 22 January 2015

Longlines incidentally capture vulnerable species including sea birds and sea turtles. Bycatch of seabirds, sea turtles, marine mammals and sharks in pelagic longline tuna fisheries threatens some populations with extinction. Purse seines can also incidentally capture sea turtles. The Indian Ocean Tuna Commission (IOTC) has implemented several management measures addressing these incidental captures.

Regarding sea birds, a 2010 resolution, superseding previous measures, requires, when south of 25oS, use of at least two seabird mitigation methods selected from two lists of nine alternatives (IOTC, 2010b).

A 2009 resolution requires member countries to report data on sea turtle interactions and for vessels to follow sea turtles handling and release guidelines and posses and use specified turtle release equipment (IOTC, 2009c). Purse seine vessels are not allowed to encircle sea turtles while setting their nets (IOTC 2013).

There are extremely low bycatch levels in pole-and-line fisheries, where bycatch that does occur generally consists of juvenile kawakawa tuna (Euthynnus affinis_), frigate mackerel (Auxis rochei_), mahimahi (Coryphaena hippurus), and rainbow runner (Elagatis bupinnulata). Discards are believed to have high post release survival rates due to the use of barbless hooks and flick-off practices (FAO, 1997). However, concern over bycatch of reef fish and juvenile classes of target species in baitfish fisheries that supply live bait to pole-and-line fisheries has been raised, as have other ecological issues (ecosystem effects of removal of baitfish species, overexploitation of target baitfish species, habitat degradation) and socioeconomic issues (food security impacts with coastal communities) (FAO, 2008; Gillett, 2010).

Required observer coverage rates and compliance with these rates are low in the Indian Ocean. In 2016, the Commission adopted a new resolution to develop a pilot program to promote the regional observer scheme of the IOTC {IOTC 2016}.

Indonesia
Longlines

Last updated on 5 March 2013

Bycatch of seabirds, sea turtles, marine mammals and sharks in purse seine and pelagic longline tuna fisheries threatens some populations with extinction. Bycatch of juvenile tunas and unmarketable species and/or sizes of other fish in purse seine fisheries, and juvenile swordfish in longline fisheries, contribute to the overexploitation of some stocks, and is an allocation issue among gear types and fishing nations (Gilman, 2011). Bycatch of several vulnerable species groups, including sea turtles, marine mammals and sharks, has been documented in gillnet fisheries (e.g., Gilman et al., 2009).

IOTC conducted a level 2 assessment across species subject to fishing mortality in various purse seine and longline fisheries (Murua et al., 2006). Findings were that pelagic and coastal sharks and teleosts are of relatively highest risk from mortality in assessed longline and purse seine fisheries.

The following binding measures have been adopted by IOTC to address bycatch in IOTC-managed longline and purse seine tuna fisheries (Gilman, 2011):

Seabirds: A 2010 resolution, superseding previous measures, requires, when south of 25ºS, use of at least two seabird mitigation methods selected from two lists of nine alternatives.

Sea turtles: A 2009 resolution requires members to report data on sea turtle interactions and for vessels to follow sea turtles handling and release guidelines and possess and use specified turtle release equipment. Purse seine vessels are required to: (i) Avoid encircling sea turtles; (ii) when a turtle is encircled or entangled, take measures to safely release the turtle, including stopping the net roll as soon as the turtle comes out of the water, disentangling the turtle before resuming net roll, and to the extent practicable, resuscitating the turtle before returning it to the water; and (iii) release all turtles observed entangled in FADs or other gear. Longline vessels are encouraged to use whole fish bait.

Sharks: A 2005 resolution requires: (i) annual reporting of data on shark catches; (ii) keep all parts of retained sharks, excluding head, guts and skins, to the point of first landing; (iii) have onboard fins that total < 5% of the weight of sharks onboard, up to the first point of landing, or otherwise ensure compliance with the 5% rule through certification, observer monitoring or other method. IOTC prohibits the retention, transshipment or landing of all species of thresher sharks, intended to address concerns over the status of the bigeye thresher shark (Aliopias superciliosus), but applicable to all thresher species due to the difficulty in differentiating between bigeye and other thresher species.

Juvenile tunas: To ease pressure on juvenile and small tunas, temporal one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012. Encourages retention and landing of all purse seine-caught bigeye, skipjack and yellowfin, and incidental species.

The Indonesian fisheries authority recently issued the Minsiterial decree number 12 year 2012 to regulate the management and conservation of bycatch and ecologically related species on tuna fisheries, which includes sharks, turtles, seabirds and mammals.

In October 2010, Indonesia produced a National Plan of Action for Sharks (NPOA-Shark), which addresses key issues and actions for shark and ray management in Indonesia. The key actions suggested in the NPOA include: 1) Review of the status of shark- and ray fisheries in Indonesia. 2) Compilation of methods and data collection process. 3) Development of shark and ray research. 4) Improvement of management measures 5) Raising of concerns and awareness concerning the shark and ray fisheries in Indonesia. 6) Institutional Strengthening. As a member of the Indian Ocean Tuna Commission (IOTC) since 2007, Indonesia is required to comply with the Commission’s resolution 10/12, concerning the protection of thresher sharks.

Commercial species of shark identified in Indonesia’s NPOA-Sharks include: Pelagic Thresher, Bigeye Thresher, Silky Shark, Tiger Shark, Shortfin and Longfin Mako, Scalloped Hammerhead , Spottail Shark, Crocodile Shark, Western Angel Shark, Spinner Shark, dogfish Squalidae spp.

The Reserach Institute for Tuna Fisheries observer program recorded 51 turtles caught by tuna longliners during 2005 – 2010, where 14 were dead and 37 were released. These included Leatherback, Olive ridley, Loggerhead, Hawksbill and Green turtles. WWF Indonesia has trained 400 longline vessels crew to collect data and on how to handle sea turtle bycatch, on how to treat wounded turtle and releasing techniques to increase the survival rate of the animal. During the period from 2006 – 2012, data on turtle bycatch was recorded from 35 vessels, which documented 71 (58 were alive and 13 were dead) (IOTC, 2012b).

Purse seines

Last updated on 17 February 2011

Bycatch of seabirds, sea turtles, marine mammals and sharks in purse seine and pelagic longline tuna fisheries threatens some populations with extinction.Bycatch of juvenile tunas and unmarketable species and/or sizes of other fish in purse seine fisheries, and juvenile swordfish in longline fisheries, contributes to the overexploitation of some stocks, and is an allocation issue among gear types and fishing nations (Gilman and Lundin, 2010; Gilman, In Press).

Yellowfin tuna are harvested with a diverse variety of gear types, from small-scale artisanal fisheries in Pacific Island and Southeast Asian waters to large, distant-water longliners and purse seiners that operate widely in equatorial and tropical waters. Purse seiners catch a wide size range of yellowfin tuna, whereas the longline fishery takes mostly adult fish (WCPFC 2007).

IOTC sea turtle CMM
A 2009 resolution requires members to report data on sea turtle interactions and for vessels to follow sea turtles handling and release guidelines and posses and use specified turtle release equipment (IOTC, 2009c).Purse seine vessels are required to: (i) Avoid encircling sea turtles; (ii) when a turtle is encircled or entangled, take measures to safely release the turtle, including stopping the net roll as soon as the turtle comes out of the water, disentangling the turtle before resuming net roll, and to the extent practicable, resuscitating the turtle before returning it to the water; and (iii) release all turtles observed entangled in FADs or other gear.Longline vessels are encouraged to use whole fish bait.

IOTC shark CMM
A 2005 resolution requires: (i) annual reporting of data on shark catches; (ii) keep all parts of retained sharks, excluding head, guts and skins, to the point of first landing; (iii) have onboard fins that total < 5% of the weight of sharks onboard, up to the first point of landing, or otherwise ensure compliance with the 5% rule through certification, observer monitoring or other method (IOTC, 2005).IOTC (2010c) prohibits the retention, transshipment or landing of all species of thresher sharks, intended to address concerns over the status of the bigeye thresher shark (Aliopias superciliosus), but applicable to all thresher species due to the difficulty in differentiating between bigeye and other thresher species.

IOTC CMM relating to bycatch of Juvenile and Small Tunas / Unmarketable Species and/or Sizes of Fish
Temporal one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012 (IOTC, 2010a).Encourages retention and landing of all purse seine-caught bigeye, skipjack and yellowfin, and incidental species (IOTC, 2010d).

IOTC conducted a Level 2 ecological risk assessment across species subject to fishing mortality in purse seine and longline fisheries (Mura et al., 2009).

Seine nets

Last updated on 19 April 2010

Fishing gears for the tuna fishery in Indonesia are longliner, traditional hook & line, and purse-seiner combined with FADs – Fish Aggregation Devices. Longline fishing is controversial in some areas because the lines can lead to bycatch, in endangered species such as sea turtles and this can sometimes have a significant effect on populations.

NOAA Fisheries has provided funding to World Wildlife Fund-Indonesia (WWF) to supportsea turtle conservation and management institutional capacity building Indonesia. The focus is on commercial and traditional fisheries with significant sea turtle interactions. The project emphasizes participation of the industry on a voluntary basis and works closely with recognized industry groups, including the Indonesia Tuna Association (ASTUIN) and the Indonesia Tuna Longline Association (ATLI).

Through this project, sea turtle bycatch in tuna longline industries in Indonesia was surveyed from May to September 2005 in several fishing ports, i.e. Muara Baru (Jakarta), Cilacap (Central Java), Bitung (North Sulawesi), Kendari/Bau-bau (Southeast Sulawesi) and Makassar/Bone (South Sulawesi). Longline fishermen (boat captains and crews) and non-longline fishermen (i.e. those using gillnets and purse seine) were interviewed. Most respondents (95%) acknowledged usually catching at least one sea turtle per month. With an estimated 1,600 Indonesian tuna longline vessels catching three sea turtles per trip (one trip takes three months on average), the average sea turtle bycatch is estimated to range from 6,400 to 19,200 animals per annum (p.a.). The most common sea turtle bycatch species in both the Indian and Pacific Oceans is loggerhead turtles. Leatherback turtles were also frequently caught in both oceans, although catch rates in the Pacific Ocean were higher. Indonesian tuna longline bycatch in the Pacific is estimated to be 256 to 768 animals p.a. for leatherback turtles and 768 to 2,304 animals p.a. for loggerhead turtles. In the Indian Ocean, bycatch for leatherback turtles is estimated to be 1,349 to 4,032 animals p.a., while bycatch for loggerhead turtles is 4,032 to 12,098 animals p.a. This Indian Ocean estimate exceeds Lewison’s (2004) bycatch calculation for the year 2000, of 4,000 leatherback turtles and 6,000 loggerhead turtles, and confirms the importance of longline fisheries in bycatch issues in Indonesia.

Together with some early adopters in the Tuna longline (Pelabuhan Ratu-West Java, Benoa-Bali, Bitung-North Sulawesi) and shrimp trawl fisheries industries (Sorong-Papua), WWF initiated trial observer programs and trained crew members on appropriate release techniques that can increase survival rates of turtles captured in the gear. Gear trials will soon be implemented adjusting long-line hooks with a more circular model that reduces the hook-up rate of turtles and allows for easier release in case a turtle is hooked after all.However, since the hook is still imported from USA, then the implementation of it is still on piloting scheme (under collaboration program of WWF Indonesia and the Research Center of Captured Fisheries Ministry of Marine Affairs and Fisheries (Lovita, 2007).

Mechanized lines

Last updated on 19 April 2010

Fishing gears for the tuna fishery in Indonesia are longliner, traditional hook & line, and purse-seiner combined with FADs – Fish Aggregation Devices. Longline fishing is controversial in some areas because the lines can lead to bycatch, in endangered species such as sea turtles and this can sometimes have a significant effect on populations.

NOAA Fisheries has provided funding to World Wildlife Fund-Indonesia (WWF) to supportsea turtle conservation and management institutional capacity building Indonesia. The focus is on commercial and traditional fisheries with significant sea turtle interactions. The project emphasizes participation of the industry on a voluntary basis and works closely with recognized industry groups, including the Indonesia Tuna Association (ASTUIN) and the Indonesia Tuna Longline Association (ATLI).

Through this project, sea turtle bycatch in tuna longline industries in Indonesia was surveyed from May to September 2005 in several fishing ports, i.e. Muara Baru (Jakarta), Cilacap (Central Java), Bitung (North Sulawesi), Kendari/Bau-bau (Southeast Sulawesi) and Makassar/Bone (South Sulawesi). Longline fishermen (boat captains and crews) and non-longline fishermen (i.e. those using gillnets and purse seine) were interviewed. Most respondents (95%) acknowledged usually catching at least one sea turtle per month. With an estimated 1,600 Indonesian tuna longline vessels catching three sea turtles per trip (one trip takes three months on average), the average sea turtle bycatch is estimated to range from 6,400 to 19,200 animals per annum (p.a.). The most common sea turtle bycatch species in both the Indian and Pacific Oceans is loggerhead turtles. Leatherback turtles were also frequently caught in both oceans, although catch rates in the Pacific Ocean were higher. Indonesian tuna longline bycatch in the Pacific is estimated to be 256 to 768 animals p.a. for leatherback turtles and 768 to 2,304 animals p.a. for loggerhead turtles. In the Indian Ocean, bycatch for leatherback turtles is estimated to be 1,349 to 4,032 animals p.a., while bycatch for loggerhead turtles is 4,032 to 12,098 animals p.a. This Indian Ocean estimate exceeds Lewison’s (2004) bycatch calculation for the year 2000, of 4,000 leatherback turtles and 6,000 loggerhead turtles, and confirms the importance of longline fisheries in bycatch issues in Indonesia.

Together with some early adopters in the Tuna longline (Pelabuhan Ratu-West Java, Benoa-Bali, Bitung-North Sulawesi) and shrimp trawl fisheries industries (Sorong-Papua), WWF initiated trial observer programs and trained crew members on appropriate release techniques that can increase survival rates of turtles captured in the gear. Gear trials will soon be implemented adjusting long-line hooks with a more circular model that reduces the hook-up rate of turtles and allows for easier release in case a turtle is hooked after all.However, since the hook is still imported from USA, then the implementation of it is still on piloting scheme (under collaboration program of WWF Indonesia and the Research Center of Captured Fisheries Ministry of Marine Affairs and Fisheries (Lovita, 2007).

Maldives
Pole-lines hand operated

Last updated on 13 August 2009

Huntington et al (2010) report that interactions with PET species is low, but lack of adequate scientific data leads to absence of any credible conclusions on this issue.

Yellowfin tuna schools have often observed associated with Bryde’s whales (Balaenoptera edeni) as both feed on same prey (Anderson, 1993; Anderson et al., 1998). Yellowfin tuna have also been frequently observed in schools of spotted dolphins and spinner dolphins (Anderson 2005).

Spain
Longlines

Last updated on 3 December 2013

Bycatch of seabirds, sea turtles, marine mammals and sharks in purse seine and pelagic longline tuna fisheries threatens some populations with extinction. Bycatch of juvenile tunas and unmarketable species and/or sizes of other fish in purse seine fisheries, and juvenile swordfish in longline fisheries, contribute to the overexploitation of some stocks, and is an allocation issue among gear types and fishing nations (Gilman, 2011). Bycatch of several vulnerable species groups, including sea turtles, marine mammals and sharks, has been documented in gillnet fisheries (e.g., Gilman et al., 2009).

IOTC conducted a level 2 assessment across species subject to fishing mortality in various purse seine and longline fisheries (Murua et al., 2006). Findings were that pelagic and coastal sharks and teleosts are of relatively highest risk from mortality in assessed longline and purse seine fisheries.

The following binding measures have been adopted by IOTC to address bycatch in IOTC-managed longline and purse seine tuna fisheries (Gilman, 2011):

Seabirds: A 2010 resolution, superseding previous measures, requires, when south of 25ºS, use of at least two seabird mitigation methods selected from two lists of nine alternatives.

Sea turtles: A 2009 resolution requires members to report data on sea turtle interactions and for vessels to follow sea turtles handling and release guidelines and possess and use specified turtle release equipment. Longline vessels are encouraged to use whole fish bait.

Sharks: A 2005 resolution requires: (i) annual reporting of data on shark catches; (ii) keep all parts of retained sharks, excluding head, guts and skins, to the point of first landing; (iii) have onboard fins that total < 5% of the weight of sharks onboard, up to the first point of landing, or otherwise ensure compliance with the 5% rule through certification, observer monitoring or other method. IOTC prohibits the retention, transshipment or landing of all species of thresher sharks, intended to address concerns over the status of the bigeye thresher shark (Aliopias superciliosus), but applicable to all thresher species due to the difficulty in differentiating between bigeye and other thresher species.

Juvenile tunas: To ease pressure on juvenile and small tunas, temporal one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012.

Sri Lanka
Drifting longlines

Last updated on 3 February 2015

Longline and gillnet fisheries typically capture incidental bycatch species including sea turtles and sea birds and potentially marine mammals. There are five Acts in Sri Lanka that pertain to the protection and management of these bycatch species. These include 1) Fauna and Flora protection Act 1937, 2)Fisheries and Aquatic Resources Act NO. 2 (1996), 3) National Environment Act NO. 47 1980, 4) Coast Conservation Act 1981 and 5) Marine Pollution Prevention Act of Sri Lanka.

The National Aquatic Resources and Research (NARA) Development Agency has conducted on-board research studies to examine bycatch interactions. Sri Lanka reports that sea bird interactions do not occur in their fisheries due to the location of the fisheries and the nature of the fisheries.For example, Sri Lanka indicates that the small nature of their longline vessels reduces any potential sea bird interactions from occurring. In addition, Sri Lanka suggests the the monofilament gear used in the gillnet fisheries is visible to sea birds and therefore reduces any chance for interactions to occur.

Sea turtles are protected under the Fauna and Flora Protection Act and Fisheries and Aquatic Resources Act. Large-scale drift gillnets are restricted to being 2.5 km in length or less, which reduces turtle entanglements. Longlines typically use circle and not “J” hooks. A research study conducted by the NARA, indicated that sea turtle bycatch in the Sri Lankan gillnet and longline fisheries is low. However, it needs to be noted that logbook data currently used to report sea turtle interactions is of poor quality.

Marine mammals are prohibited from being captured in Sri Lanka under the Fisheries and Aquatic Resources Act No. 2. No recordings of incidental captures of marine mammals have been made in Sri Lanka. However, logbook recordings are poor and therefore the NARA will be conducted research on marine mammals in the future (Hewapathirana et al. 2014.

In addition, because Sri Lanka is a cooperating member of the IOTC they must comply with their management measures. Vessels must take reasonable steps to release any incidentally captured cetaceans and to report incidental captures {IOTC 2013l}.Any interactions between vessel and sea turtles must be reported to the Commission and fishermen are required to attempt proper mitigation measures, aid in recovery when necessary and release all incidentally captured sea turtles.Longline vessels must carry line cutters and dehooking devices. Countries are also requested to conduct studies on the use ofcircle hooks and whole finfish bait, handling techniques and other mitigation measures. {IOTC 2013l}.All interactions with sea birds must be recorded and countries must provide information on how they are implementing observer programs to aid in the recording and reporting of these interactions.Mitigation measures are required, south of 25 degrees two pre-approved mitigation measures must be used, but mitigation methods in other areas must be used as well {IOTC 2013l}.

Thailand
Longlines

Last updated on 22 June 2012

Thai vessels do not record interactions with marine mammals in the Indian Ocean (Saikliang and Nootmorn 2011).

Bycatch of seabirds, sea turtles, marine mammals and sharks in purse seine and pelagic longline tuna fisheries threatens some populations with extinction. Bycatch of juvenile tunas and unmarketable species and/or sizes of other fish in purse seine fisheries, and juvenile swordfish in longline
fisheries, contribute to the overexploitation of some stocks, and is an allocation issue among gear types and fishing nations (Gilman, 2011). Bycatch of several vulnerable species groups, including sea turtles, marine mammals and sharks, has been documented in gillnet fisheries (e.g., Gilman et al., 2009).

IOTC conducted a level 2 assessment across species subject to fishing mortality in various purse seine and longline fisheries (Murua et al., 2006). Findings were that pelagic and coastal sharks and teleosts are of relatively highest risk from mortality in assessed longline and purse seine fisheries. The following binding measures have been adopted by IOTC to address bycatch in IOTC-managed longline and purse seine tuna fisheries (Gilman, 2011):

Seabirds: A 2010 resolution, superseding previous measures, requires, when south of 25oS, use of at least two seabird mitigation methods selected from two lists of nine alternatives.

Sea turtles: A 2009 resolution requires members to report data on sea turtle interactions and for vessels to follow sea turtles handling and release guidelines and possess and use specified turtle release equipment. Longline vessels are encouraged to use whole fish bait.

Sharks: A 2005 resolution requires: (i) annual reporting of data on shark catches; (ii) keep all parts of retained sharks, excluding head, guts and skins, to the point of first landing; (iii) have onboard fins that total < 5% of the weight of sharks onboard, up to the first point of landing, or otherwise ensure compliance with the 5% rule through certification, observer monitoring or other method. IOTC prohibits the retention, transshipment or landing of all
species of thresher sharks, intended to address concerns over the status of the bigeye thresher shark (Aliopias superciliosus), but applicable to all thresher species due to the difficulty in differentiating between bigeye and other thresher species.

Juvenile tunas: To ease pressure on juvenile and small tunas, temporal one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012. Encourages retention and landing of all purse seine-caught bigeye, skipjack and yellowfin, and incidental species.

OTHER TARGET AND BYCATCH SPECIES

Last updated on 22 January 2015

Large longline vessels generally catch older age classes of bigeye tuna (Thunnus obesus) and bluefin tunas (T. maccoyii [southern], T. orientalis [Pacific] and T. thynnus [Atlantic]) for the sashimi market and some longline fleets target albacore (T. alalunga) for canning.Purse seine vessels target younger age classes of skipjack (Katsuwonus pelamis) and yellowfin (T. albacares) tuna for canning with incidental catch of bigeye tuna

Purse seine sets on anchored and drifting Fish Aggregating Devices (FADs) and natural floating objects (logs, flotsam) is widespread, with about half of tropical tuna catches coming from FAD sets (Fonteneau et al., 2000).FAD sets have high catch rates of small and juvenile bigeye and yellowfin tunas and unmarketable species and sizes of other fish species, as well as high sea turtle and shark bycatch rates, relative to unassociated sets (Fonteneau et al., 2000; IOTC, 2002; Romanov, 2002; Bromhead et al., 2003; Secretariat of the Pacific Community, 2006; WCPFC, 2007; An et al., 2009; Nicol et al., 2009).Networks of thousands of artificial drifting and anchored FADs aggregate tunas from surrounding waters and possibly act as ‘ecological traps’ of pelagic species by altering their natural spatial and temporal distributions, habitat associations, migration patterns and residence times (Marsac et al., 2000; Bromhead et al., 2003; Hallier and Gaertner, 2008; WCPFC, 2009; Dagorn et al., 2010).

Smaller swordfish are often discarded in pelagic longline tuna fisheries due to minimum size requirements or low market value (Cramer, 2003; Ward et al., 2008).

There are extremely low bycatch levels in pole-and-line fisheries, where bycatch that does occur generally consists of juvenile kawakawa tuna (Euthynnus affinis), frigate mackerel (Auxis rochei), mahimahi (Coryphaena hippurus), and rainbow runner (Elagatis bupinnulata).Discards are believed to have high post release survival rates due to the use of barbless hooks and flick-off practices (FAO, 1997).However, concern over bycatch of reef fish and juvenile classes of target species in baitfish fisheries that supply live bait to pole-and-line fisheries has been raised, as have other ecological issues (ecosystem effects of removal of baitfish species, overexploitation of target baitfish species, habitat degradation) and socioeconomic issues (food security impacts with coastal communities) (FAO, 2008; Gillett, 2010).

Between 1995 and 2003, the FAD component of the purse seine fishery represented 48-66% of the sets undertaken (60-80% of the positive sets) and took 36-63 % of the yellowfin catch by weight (59-76% of the total catch).

Preliminary quantitative estimates of the main bycatch species and species groups (billfishes, sharks, rays and fin fishes) were made for the whole purse seine fishery since 2003. Data are from the French and Spanish observer programs from 2003 to 2007, representing a total of 1958 observed sets (4% of the total number of sets during this period). Annual raising factors by fishing mode based on tuna production (tonnes per 1000 tonnes of tuna landed) were estimated for each species group from logbooks and observer information stratified by quarter, fishing area and fishing mode. According to these estimations, total bycatch was estimated at 9,585 tonnes, corresponding to 35.5 tonnes bycatch per 1000 tonnes of tuna landed. Tuna discards represents 54% of the total amount, followed by other fin fish (34%), sharks (10%), billfishes (1.5%) and rays (0.7%) (IOTC, 2009).

These mean ratios were applied to the whole purse seine fishery annual catches from 2003 to 2008 to compute total bycatches by species groups, and then distributed within the groups according to the proportion in weight of the main species or families. The bulk of the bycatch consisted of tuna discards (average annual catch 6,700 tonnes; range 5,100-8,300 tonnes). The annual bycatch of all other groups averaged some 4,000 tonnes (range 2,750-4,400 tonnes). Of this the majority was made up of “fin fishes”, with an annual mean catch close to 2,500 tonnes (range 1550-2,800 tonnes). The main species was rainbow runner (Elagatis bipinnulatus, 37% of the total), followed by triggerfishes (Balistidae, 24%), dolphinfishes (Coryphaena spp., 11%) and carangids (Carangidae, 7%), with the balance (21%) being made up of some 50 other species. Most were caught under FADs (95%). Fin fish species composition between FAD and log schools was rather similar, although there were more dolphinfishes on FADs, and the greatest diversity was from free schools. The next most important bycatch group was “sharks”, with a total average annual catch close to 1,300 tonnes (range 1,000-1,650 tonnes). Shark bycatch was dominated by carcharhinids, the most important being the silky shark (Carcharhinus falciformis, 79%) followed by the oceanic whitetip shark (C. longimanus, 11%). 97% of sharks were caught on FADs. Shark species composition was quite similar between FAD and free schools sets. “Billfish” bycatch was relatively low, with an average annual catch of 180 tonnes (range 140-210 tonnes). The most important species were marlins (70%, mainly M. indica and T. audax) and sailfishes (27%). Most billfishes (72%) were caught on FADs. Billfish species composition was quite similar between FAD and log sets. “Rays” were caught in smaller quantities, with an average annual catch of 50 tonnes (range 40-70 tonnes). 65% of rays were caught on FADs. The most important species group was the Mobulidae (42%), followed by the giant manta (Manta birostris, 37%) and other and unidentified rays (20%). Ray species composition is rather similar between FAD and free schools, but with a larger diversity on free schools. Overall, discards by the purse seine fishery (excluding tuna discards) remains relatively low when compared to many other fisheries, with the large majority coming from FAD sets (IOTC, 2009).

India
Hooks and lines

Last updated on 21 June 2012

Reefish are used as baitfish in the pole and line fishery around Lakshadweep islands. Caesionids (Spratelloides delicatulus), clupeids, and apogonids are the principal fish caught for use as baitfish around Minicoy islands (Naseer 1999; Lakshadweep Development Report 2007). Over the years, increase in pole and line fishing effort has lead to seasonal shortage of baitfish in many of the Lakshadweep islands (Gopakumar 1991).

Bait fish is collected from lagoon and reeef areas around Minicoy, Agatti, Suheli, Perumal Par, Valiapani, Bitra and Cheriapani (Lakshadweep Development Report 2007). A detailed study of different species exploited in the bait fish fisheries is available in Gopakumar, et.al., (1991); Pillai, et. al., (2002).

Other fish which are caught as bycatch in handline and hook & line fisheries include snappers, groupers, baracudas, carangids, dolphin fish, perches, sharks and rays. These fish constitute around one fourth of the total fish production in the islands caught using traditional gear like hook and line, surface trolling and other minor gears.

Indonesia
Longlines

Last updated on 5 March 2013

There are at least 5 species of billfish recorded as bycatch from Indonesian tuna longliners operated in the Indian Ocean. These were 3 species of marlins; black marlin (BLM) (Makaira indica), blue marlin (BLZ) (Makaira mazara), striped marlin (MLZ) (Tetrapturus audax), and two non-marlin species: sailfish (Istiophorus platypterus) and the swordfish (Xiphias gladius) (IOTC, 2012b).

Large longline vessels generally catch older age classes of bigeye tuna (Thunnus obesus) and bluefin tunas (T. maccoyii [southern], T. orientalis [Pacific] and T. thynnus [Atlantic]) for the sashimi market and some longline fleets target albacore (T. alalunga) for canning. Purse seine vessels target younger age classes of skipjack (Katsuwonus pelamis) and yellowfin (T. albacares) tuna for canning with incidental catch of bigeye tuna.

Smaller swordfish are often discarded in pelagic longline tuna fisheries due to minimum size requirements or low market value (Cramer, 2003; Ward et al., 2008).

Purse seines

Last updated on 17 February 2011

IOTC established a regional observer program in 2009, which will require 5% coverage of sets for vessels > 24 m overall length for each gear type while fishing in the IOTC Area (AIDCP, 2009a).IOTC will further require, by January 2013, 5% coverage for vessels < 24 m overall length when fishing at grounds outside their Exclusive Economic Zone (AIDCP, 2009a; IOTC, 2010e).The IOTC observer program will be operated by Member states (IOTC, 2010e).

Seine nets

Last updated on 19 April 2010

Data from IOTC (2005) noted that based on research vessel undertook purse seine and longline fishing in the eastern Indian Ocean between 2001 and 2005, about fifteen families with about 30 species of fishes and one family of octopus were caught by purse seine and longline operations targeted and caught yellowfin, bigeye and skipjack tunas. Other species caught included mainly sharks (thresher, blue, white-tip, spot tail, crocodile and silky) and also stringrays.

Mechanized lines

Last updated on 19 April 2010

Data from IOTC (2005) noted that based on research vessel undertook purse seine and longline fishing in the eastern Indian Ocean between 2001 and 2005, about fifteen families with about 30 species of fishes and one family of octopus were caught by purse seine and longline operations targeted and caught yellowfin, bigeye and skipjack tunas. Other species caught included mainly sharks (thresher, blue, white-tip, spot tail, crocodile and silky) and also stringrays.

Korea, Republic of
Longlines

Last updated on 21 June 2012

Data collection on bycatch is poor for Korean longliners operating in the Indian Ocean, especeially for marine turtles and marine mammals. Limited data is available on bycatch of sharks caught by Korean longliners operating in the Indian Ocean. In 2010, 11 mt of sharks were retained by Korean longliner, while 54,358 kgs of blue sharks, 1796 kgs of Mako sharks were reported by longliners (Kim et al., 2011).

15 Yellow nosed albatross, 24 Black browed albatross, 9 Buller’s albatross, 1 Cape petrel, 2 Grey headed albatross, 1 Southern Giant albatross, 11 Wandering albatross and 3 Shy albatross were observed through national observer porgram in the IOTC region (Kim et al., 2011).

Maldives
Pole-lines hand operated

Last updated on 13 August 2009

6 species of marine turtles are reported to interact with tuna fisheries in the Indian Ocean (IOTC 2011). However, there are no reported interactions between pole and line fisheries with turtles or marine mammals in Maldives tuna fisheries.
Relatively small quantities of yellowfin tuna are caught as by-catch in the pole and line fisheries. Substantial quantities of skipjack are caught around FADS, which can lead to unwanted by-catch of many non-target species. Livebait used in the pole and line tuna fisheries needs to be quantified on a regular basis. Discards in the skipjack targeted pole and line fisheries have not been formally quantified. Collection of baitfish is not monitored and operations during the night using lights can lead to unwanted by-catch of other non-target species.

Spain
Longlines

Last updated on 3 December 2013

Large longline vessels generally catch older age classes of bigeye tuna (Thunnus obesus) and bluefin tunas (T. maccoyii [southern], T. orientalis [Pacific] and T. thynnus [Atlantic]) for the sashimi market and some longline fleets target albacore (T. alalunga) for canning.Purse seine vessels target younger age classes of skipjack (Katsuwonus pelamis) and yellowfin (T. albacares) tuna for canning with incidental catch of bigeye tuna

Smaller swordfish are often discarded in pelagic longline tuna fisheries due to minimum size requirements or low market value (Cramer, 2003; Ward et al., 2008).

Sri Lanka
Drifting longlines

Last updated on 3 February 2015

In addition to target tuna species (bigeye, skipjack and yellowfin), billfish, sharks and rays are also incidentally captured in Sri Lanka’s fisheries. In 2013, bycatch made up 3% of the total catch, with sharks and rays being the primary represented species.Bycatch of sharks is reported to occur more frequently in the gillnet and longline/gillnet combination fisheries compared to the longline fishery.Several species of rays are commonly caught in gillnet fisheries, including manta and devil rays. Commonly captured shark species in this fishery include silky and hammerhead sharks. In the longline fishery silky sharks are the primary incidentally captured shark species.Overall, silky shark made up 68% of the reported shark catch during 2013.

Sri Lanka has a National Plan of Action for Sharks that was made public in 2014. There is a species identification guide available, on-site sampling programs have been improved to include all species of sharks, Sri Lanka enforces the rules that sharks must be landed with their fins attached and the prohibition for the retention of thresher sharks.Sri Lanka reports continuing issues with data reporting in their current logbooks, although they are working on improving them (Hewapathirana et al. 2014).

Thailand
Longlines

Last updated on 22 June 2012

Large longline vessels generally catch older age classes of bigeye tuna (Thunnus obesus_) and bluefin tunas (_T. maccoyii [southern], T. orientalis [Pacific] and T. thynnus [Atlantic]) for the sashimi market and some longline fleets target albacore (T. alalunga_) for canning. Purse seine vessels target younger age classes of skipjack (Katsuwonus pelamis_) and yellowfin (T. albacares) tuna for canning with incidental catch of bigeye tuna. Smaller swordfish are often discarded in pelagic longline tuna fisheries due to minimum size requirements or low market value (Cramer, 2003; Wardet al., 2008).

Thai tuna longliners do not record shark by-catch from their operations in the Indian Ocean. By-catch study by Thai Dept. of Fisheries Research vessel showed that blacktip sharks, blue sharks, crocodile sharks, silky sharks, blue marlins, dolphin fish and sting rays were caught by longliners operating in the Indian Ocean. Other species reported included Great barracuda, Lancet fish, sickel pomfret, snake mackerel, swordfish and wahoo (Saikliang and Nootmorn 2011).

HABITAT

Last updated on 5 July 2011

In general, primary gear used to catch yellowfin tuna, including purse seine, pelagic longline and pole-and-line gear, do not come in direct contact with the seafloor.Lost and discarded gillnet gear can damage coastal habitats.

Indonesia
Longlines

Last updated on 19 April 2010

The impact on marine habitats in longlining is far less than that of seafloor trawling or dredging. With longline gear, juvenile or unwanted fish can be identified and returned to the sea, very often unharmed depending on the species. However, due to the length of time fish remain on the hook, many are inadvertently killed. Strict regulation and scientific observation are the most important steps towards ecological sustainability no matter what the fishing method.

Purse seines

Last updated on 17 February 2011

Pelagic gear does not come in direct contact with the seafloor.Lost and discarded gear can damage coastal habitats.

Seine nets

Last updated on 19 April 2010

The impact on marine habitats in longlining is far less than that of seafloor trawling or dredging. With longline gear, juvenile or unwanted fish can be identified and returned to the sea, very often unharmed depending on the species. However, due to the length of time fish remain on the hook, many are inadvertently killed. Strict regulation and scientific observation are the most important steps towards ecological sustainability no matter what the fishing method.

Mechanized lines

Last updated on 19 April 2010

The impact on marine habitats in longlining is far less than that of seafloor trawling or dredging. With longline gear, juvenile or unwanted fish can be identified and returned to the sea, very often unharmed depending on the species. However, due to the length of time fish remain on the hook, many are inadvertently killed. Strict regulation and scientific observation are the most important steps towards ecological sustainability no matter what the fishing method.

Maldives
Pole-lines hand operated

Last updated on 13 August 2009

The fishery is conducted in pelagic waters targeting surface swimming stocks and stocks surrounding FADS.
Baitfish fishery in Maldives is reported to have caused substantial damage to reefs in the past (Anderson and Saleem 1995), although there is no evidence to state that such practices continue today. More recent data on bait fish collection shows that it is collected using lights at night.

Spain
Longlines

Last updated on 3 December 2013

In general, primary gear used to catch yellowfin tuna, do not come in direct contact with the seafloor.

Sri Lanka
Drifting longlines

Last updated on 5 December 2009

According to MFAR (2007), degradation of the coastal and marine environment which includes coastal pollution and the threats to the sustainability of coastal habitats has emerged as a major problem adversely affecting the fishing industry (MFAR 2007).However, no specific information found regarding to the impact of yellowfin tuna fisheries to the habitat in Sri Lanka.

Thailand
Longlines

Last updated on 24 May 2012

In general, primary gear used to catch yellowfin tuna, including purse seine, pelagic longline and pole-and-line gear, do not come in direct contact with the seafloor. Lost and discarded gillnet gear can damage coastal habitats.

MARINE RESERVES
Indonesia
Longlines

Last updated on 5 March 2013

In 2011, there were over 88 MPAs in Indonesia, covering an area of 13, 9 million Ha. The government hope to achieve 20 million Ha of MPAs by 2020. One large MPA situated in the Indian Ocean is Savu Marine National Park, in East Nusa Tenggara province, encompassing an area of 3.5 million hectares.

To ease pressure on juvenile and small tunas, IOTC has adopted a one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012. Several coastal States also have time/area closures in domestic waters (e.g., Sri Lanka).

Appended content

There are 35 marine conservation areas (protected areas) in Indonesia by 2002, totaling 47 thousand km2. Compared to Indonesia’s total marine territory of 7.9 million km2 (including the Exclusive Economic Zone), this is far from sufficient. Many of these protected areas include mangrove forests, the spawning grounds for shrimp and other marine biotas.

Purse seines

Last updated on 17 February 2011

There are 35 marine conservation areas (protected areas) in Indonesia by 2002, totaling 47 thousand km2. Compared to Indonesia’s total marine territory of 7.9 million km2 (including the Exclusive Economic Zone), this is far from sufficient. Many of these protected areas include mangrove forests, the spawning grounds for shrimp and other marine biotas.

IOTC established a one month per year closure to longline and purse seine vessels of an area off Somalia, which is in effect from 2011 to 2012, in an attempt to reduce mortality of small and juvenile tunas (IOTC, 2010a).

Seine nets

Last updated on 19 April 2010

There are 35 marine conservation areas (protected areas) in Indonesia by 2002, totaling 47 thousand km2. Compared to Indonesia’s total marine territory of 7.9 million km2 (including the Exclusive Economic Zone), this is far from sufficient. Many of these protected areas include mangrove forests, the spawning grounds for shrimp and other marine biotas.

Mechanized lines

Last updated on 19 April 2010

There are 35 marine conservation areas (protected areas) in Indonesia by 2002, totaling 47 thousand km2. Compared to Indonesia’s total marine territory of 7.9 million km2 (including the Exclusive Economic Zone), this is far from sufficient. Many of these protected areas include mangrove forests, the spawning grounds for shrimp and other marine biotas.

Sri Lanka
Drifting longlines

Last updated on 5 December 2009

The Sri Lankan Coast Conservation Act No 57 of 1981 (and its amendments, 1988) provide the legal foundation for activities within the coastal zone. As mandated by the Act, the Coastal Conservation Department developed a Coastal Zone Management Plan (CZMP) for the management of the coastal zone and this document is updated every five years. Special Area Management (SAM) is managing sites of special significance and public access, regulatory mechanisms, and integrating coastal fisheries aquaculture with coastal zone management. SAM actions articulated under the CZMP include the management of MCPAs.

Currently, there are 13 MCPAs in Sri Lanka, covering area of 314,754 ha. Within this list, there are only 2 Marine Sanctuaries, namely Bar Reef (30,670 ha) and Rumassala (1,707 ha). See: List of MCPAs .

Thailand
Longlines

Last updated on 22 June 2012

To ease pressure on juvenile and small tunas, IOTC has adopted a one month per year closure to longline and purse seine vessels of an area off Somalia is in effect from 2011 to 2012. Several coastal States also have time/area closures in domestic waters (e.g., Sri Lanka).

FishSource Scores

Last updated on 13 November 2017

SELECT SCORES

MANAGEMENT QUALITY

As calculated for 2015 data.

The score is ≥ 6.

There are interim target and limit reference points in place. The IOTC adopted a precautionary management approach in 2012 that will utilize reference points, harvest control rules and management strategy evaluation.

As calculated for 2015 data.

The score is ≥ 6.

Managers have adopted measures to reduce catches of yellowfin by 5-15% (depending on the fleet) but this is below the scientifically requested 20%.

As calculated for 2015 data.

The score is < 6.

Yellowfin tuna catches have been increasing since 2012 to unsustainable levels. In addition, there are significant issues with the quality of data reported by some countries to the Commission.

STOCK HEALTH:

As calculated for 2015 data.

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

The Ratio SSB/SSBmsy is 0.890 . The SSB=SSBmsy is 1.00 .

The underlying Ratio SSB/SSBmsy/SSB=SSBmsy for this index is 89.0%.

As calculated for 2015 data.

This measures the Harvest rate as a percentage of the F management target.

The Harvest rate is 1.11 (Y/TSB). The F management target is 1.00 .

The underlying Harvest rate/F management target for this index is 111%.

HUMAN RIGHTS ABUSE RISK

High Medium Low

This indicates the potential risk of human rights abuses for all fisheries operating within this stock or assessment unit. If there are more than on risk level noted, individual fisheries have different levels. Click on the "Select Scores" drop-down list for your fisheries of interest.

No data available for recruitment
DATA NOTES

F and SSB are provided relative to MSY (F/FMSY, B/BMSY) and reference points have been set accordingly. F to be adopted at low biomass is not defined and there is no set TAC. Therefore, Scores 1, 2 and 3 have been determined qualitatively (please mouse-over for explanation).

 

Download Source Data

Registered users can download the original data file for calculating the scores after logging in. If you wish, you can Register now.

Fishery Improvement Projects (FIPs)

SELECT FIP

Access FIP Public Report

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

Comments:

Progress ratng A. Stage 4 activities over past 12 months.

 

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

Certifications

Marine Stewardship Council (MSC)

SELECT MSC

NAME

Echebastar Indian Ocean purse seine skipjack, yellowfin and bigeye tuna

STATUS

Not certified

SCORES

This fishery entered Marine Stewardship Council full assessment in January of 2013. The fishery was deemed not certified in September 2015.

Principle Level Scores:

Principle Yellowfin tuna Score Skipjack tuna Score Bigeye tuna Score
Principle 1 – Target Species 82.5 81.9 81.3
Principle 2 - Ecosystem 85.0 85.0 85.0
Principle 3 – Management System 80.5 80.5 80.5

Certification Type:

Sources

Credits

An H-H, Kwon Y-J, Kim DN, Moon DY, Hwang SJ. 2009. Effects of set type on catch of small-sized tuna by the Korean tuna purse seine fishery in the WCPO. Western and Central Pacific Fisheries Commission Scientific Committee Fifth Regular Session, 10-21 August 2009, Port Vila, Vanuatu. Information Paper Number WCPFC-SC5-2009/FT-WP-02. Western and Central Pacific Fisheries Commission, Palikir, Pohnpei, Federated States of Micronesia.

Bromhead D, Foster J, Attard R, Findlay J, Kalish J. 2003.. A review of the impacts of fish aggregating devices (FADs) on tuna fisheries. Final Report to the Fisheries Resources Research Fund. Bureau of Rural Sciences, Canberra, ACT, Australia.

Cramer, J. 2003. Distribution of juvenile swordfish (Xiphias gladius) caught by pelagic longline in the Atlantic Ocean. Col. Vol. Sci. Pap. ICCAT 55(4): 1587-1596.

Dagorn, L., Holland, K.N., Filmalter, J., Are drifting FADs essential for testing the ecological trap hypothesis? Fisheries Research (2010),
doi:10.1016/j.fishres.2010.07.002.

FAO. 2008. Fishing Gear Types. Lift nets. Food and Agriculture Organization of the United Nations, Fisheries and Aquaculture Department, Rome.

Fonteneau A, Pallares P, Pianet R. 2000. A worldwide review of purse seine fisheries on FADs. In: Le Gall JY, Cayré P, Taquet M (eds) Pêche thonière et dispositifs de concentration de poissons. Actes Colloques‐IFREMER 28:15–35.

Gillett, R. 2010. Replacing Purse Seining with Pole-and-Line Fishing in the Western Pacific: Some Aspects of the Baitfish Requirements. International Seafood Sustainability Foundation, Washington, D.C., USA.

Gilman, E. 2011. Bycatch governance and best practice mitigation technology in global tuna fisheries. Marine Policy 35: 590-609.

Hallier, J.P., Gaertner, D., 2008. Drifting fish aggregation devices could act as an ecological trap for tropical tuna species. Mar. Ecol. Prog. Ser. 353, 255-264.

IOTC. 2011a. Report of the Thirteenth Session of the IOTC Working Party on Tropical Tunas, Indian Ocean Tuna Commission, Maldives, 16-23 October 2011, 94 pp.

IOTC. 2010a. Report of the Fourteenth Session of the Indian Ocean Tuna Commission. Indian Ocean Tuna Commission, Mahé, Seychelles.

IOTC. 2010b. Report of the Twelfth Session of the IOTC Working Party on Tropical Tunas. Victoria, Seychelles, 18-25 October 2010.

IOTC. 2010c. Report of the Thirteenth Session of the Scientific Committee. Victoria, Seychelles, 6-10 December 2010. Indian Ocean Tuna Commission, Seychelles.

IOTC. 2009d. Report of the Twelfth Session of the Science Committee, Victoria, Seychelles, 30 November – 4 December 2009. Indian Ocean Tuna Commission, Mahé, Seychelles.

IOTC. 2002. Resolution 02/08 on the Conservation of Bigeye and Yellowfin Tuna in the Indian Ocean. Indian Ocean Tuna Commission, Mahé, Seychelles.

IOTC. 2015. Status of the Indian Ocean yellowfin tuna (YFT: Thunnus albacares) resource. IOTC-2015-SC18-ES04[E].

IOTC. 2013b. Summary report on the level of compliance. IOTC-2013-CoC10-03. Available at: http://www.iotc.org/files/proceedings/2013/coc/IOTC-2013-CoC10-03%5BE%5D.pdf

IOTC. 2013c. Compendium of active and pending conservation and management measures for the Indian Ocean Tuna Commission. September 15, 2013. Available at: http://www.iotc.org/files/CMM/IOTC%20-%20Compendium%20of%20ACTIVE%20CMMs%2015%20September%202013.pdf

IOTC. 2016. Status of the Indian Ocean yellowfin tuna (YFT: Thunnus albacares) resource. IOTC-2016-SC19-ES04


IOTC. 2016b. Conservation and Management Measures adopted by the IOTC at its 20th Session. IOTC Circular 2016-054.

Langley, A. 2010. Stock assessment of Yellowfin Tuna in the Indian Ocean using MULTIFAN-CL. IUTC-2010-WPTT-23.

Marsac, F., Fonteneau A., Ménard, F., 2000. Drifting FADs used in tuna fisheries: and ecological trap? In: Le Gall, J.Y., Cayré, P., Taquet, M. (Eds.), Pêche thonière et dispositifs de concentration de poisons. Actes Colloques-IFREMER. 28, 537-552.

Murua, H., Arrizabalaga, H., Huang, J., Romanov, E., Bach, P., de Bruyn, P., Chavance, P., de Molina, A., Pianet, R., Ariz, J., Ruiz, J. 2009. Ecological Risk Assessment (ERA) for Species Caught in Fisheries Managed by the Indian Ocean Tuna Commission (IOTC): A First Attempt. IOTC-2009-WPEB-20. Indian Ocean Tuna Commission, Mahé, Seychelles.

Nicol S., Lawson T., Briand K., Kirby D., Molony B., Bromhead D., Williams P., Schneiter E., Kumoru L., Hampton J. 2009. Characterisation of the tuna purse seine fishery in Papua New Guinea. Australian Centre for International Agricultural Research, Canberra, Australia. ISBN 978 1 921531 77.

Nishida. 2010. IO YFT stock assessment by ASPIC (revised version 3). Indian Ocean Tuna Commission, Victoria, Seychelles.

Romanov, E. 2002. Bycatch in the tuna purse-seine fisheries of the western Indian Ocean. Fish. Bull. 100(1): 90-105

Secretariat of the Pacific Community. 2006. Preliminary Review of the Western and Central Pacific Ocean Purse Seine Fishery. Prepared for the Internal Meeting of Pacific Island Parties to the South Pacific Regional U.S. Multilateral Treaty, March 6-8, Honolulu, Hawaii. Oceanic Fisheries Programme, Secretariat of the Pacific Community, Noumea, New Caledonia. 18 pp.

Ward, P., Porter, J., Elscot, S. 2008. Broadbill swordfish: status of established fisheries and lessons for developing fisheries. Fish and Fisheries 1(4): 317-336.

WCPFC. 2009. Conservation and Management Measure for Sharks. Conservation and Management Measre 2009-04. Sixth Regular Session, 7-11 December 2009, Papeete, Tahiti, French Polynesia. Western and Central Pacific Fisheries Commission, Palikir, Federated States of Micronesia.

WCPFC. 2007. Conservation and Management Measure to Mitigate the Impact of Fishing for Highly Migratory Fish Stocks on Seabirds. CMM 2007-04. Western and Central Pacific Fisheries Commission, Palikir, Federated States of Micronesia.

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References

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