SUMMARY

SUMMARY

IDENTIFICATION

SCIENTIFIC NAME(s)

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. 

 Sri Lanka is working on developing a vessel monitoring and observer program. A National Plan of Action for Sharks was published in 2014. Sri Lanka complies with a number of IOTC management measures. The incidental capture of sea birds and marine mammals does not appear to be an issue in Sri Lanka’s tuna fisheries.

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.

Yellowfin tuna in the Indian Ocean are overfished and undergoing overfishing. Currently, there is no catch limit for yellowfin tuna in Indian Ocean.  Catches have been over recommended level since 2011.  Recent advice calls for a 20% reduction in catches but this has yet to be adopted. 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}.  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.. There have been continuing issues with the accuracy of logbook data from Sri Lanka. IUU fishing has led to the issuance of a Red Card from the EU. The lack of an observer program has hindered accurate recording of all bycatch. Several sharks and rays are reported as incidentally captured in Sri Lanka’s tuna fisheries.

FISHSOURCE SCORES

Management Quality:

Management Strategy:

≥ 6

Managers Compliance:

≥ 6

Fishers Compliance:

< 6

Stock Health:

Current
Health:

7.6

Future Health:

7.6


RECOMMENDATIONS

RETAILERS & SUPPLY CHAIN
  • Work with IOTC Members and Cooperating Non-Contracting Parties to:
    • Ensure full compliance with Resolution 17/01, the interim rebuilding plan for yellowfin tuna.
    • Improve data collection (i.e. catches, effort, size) for all gear types, for both target and bycatch species, and reporting through measures such as electronic logbooks.
    • Develop and implement comprehensive, precautionary harvest strategies with specific timelines for all tuna stocks, including the adoption and implementation of limit and target reference points, harvest control rules, monitoring strategies, operational objectives, performance indicators, and management strategy evaluation.
    • Strengthen compliance processes and make information on non-compliance public and continue to provide evidence of compliance with all IOTC Conservation and Management Measures in a timely manner.
    • Implement a 100% observer coverage requirement for at-sea transshipment activities, as well as other measures that ensure transshipment activity is transparent and well-managed, and that all required data are collected and transmitted to the appropriate bodies in a timely manner.
    • Increase compliance with the mandatory minimum 5% longline observer coverage rates by identifying and correcting non-compliance.
    • Implement a 100% observer coverage requirement – human and/or electronic – within five years for longline fisheries.  Adopt a 100% observer coverage requirement for purse seine vessels where it is not already required and require the use of the best-available observer safety equipment, communications and procedures.
    • Adopt effective measures for the use of non-entangling FAD designs as a precautionary measure to minimize the entanglement of sharks and other non-target species, and support research on biodegradable materials and transition to their use to mitigate marine debris.
    • More effectively implement, and ensure compliance with, existing RFMO bycatch requirements and take additional mitigation action, such as improving monitoring at sea, collecting and sharing operational-level, species-specific data, and adopting stronger compliance measures, including consequences for non-compliance for all gear types.
  • Ensure all products are traceable back to legal sources. Verify source information and full chain traceability through traceability desk audits or third party traceability certification. For fisheries without robust traceability systems in place, invest in meaningful improvements to bring the fisheries and supply chain in compliance with best practices.

FIPS

  • Sri Lanka tuna and swordfish - longline:

    Stage 3, Progress Rating C

CERTIFICATIONS

No related MSC fisheries

Fisheries

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

ASSESSMENT UNIT MANAGEMENT UNIT FLAG COUNTRY FISHING GEAR
Indian Ocean IOTC France Associated purse seining
FAD-free
India Hooks and lines
Longlines
Indonesia FAD-free
Gillnets and entangling nets
Handlines hand operated
Hooks and lines
Longlines
Mechanized lines
Pole-lines hand operated
Purse seines
Seine nets
Italy Associated purse seining
FAD-free
Korea, Republic of Longlines
Malaysia Handlines hand operated
Longlines
Maldives Pole-lines hand operated
Mauritius FAD-free
Hooks and lines
Longlines
Purse seines
Mozambique Longlines
Oman Handlines hand operated
Seychelles Associated purse seining
FAD-free
Spain FAD-free
Longlines
Purse seines
Sri Lanka Drifting longlines
Thailand Handlines hand operated
Longlines
Mechanized lines

Analysis

OVERVIEW

Last updated on 3 February 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. 

IOTC
Sri Lanka
Drifting longlines

Last updated on 3 February 2015

 Sri Lanka is working on developing a vessel monitoring and observer program. A National Plan of Action for Sharks was published in 2014. Sri Lanka complies with a number of IOTC management measures. The incidental capture of sea birds and marine mammals does not appear to be an issue in Sri Lanka’s tuna fisheries.

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.

IOTC
Sri Lanka
Drifting longlines

Last updated on 3 February 2015

Yellowfin tuna in the Indian Ocean are overfished and undergoing overfishing. Currently, there is no catch limit for yellowfin tuna in Indian Ocean.  Catches have been over recommended level since 2011.  Recent advice calls for a 20% reduction in catches but this has yet to be adopted. 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}.  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.. There have been continuing issues with the accuracy of logbook data from Sri Lanka. IUU fishing has led to the issuance of a Red Card from the EU. The lack of an observer program has hindered accurate recording of all bycatch. Several sharks and rays are reported as incidentally captured in Sri Lanka’s tuna fisheries.

RECOMMENDATIONS

Last updated on 7 August 2018

Recommendations to Retailers & Supply Chain
  • Work with IOTC Members and Cooperating Non-Contracting Parties to:
    • Ensure full compliance with Resolution 17/01, the interim rebuilding plan for yellowfin tuna.
    • Improve data collection (i.e. catches, effort, size) for all gear types, for both target and bycatch species, and reporting through measures such as electronic logbooks.
    • Develop and implement comprehensive, precautionary harvest strategies with specific timelines for all tuna stocks, including the adoption and implementation of limit and target reference points, harvest control rules, monitoring strategies, operational objectives, performance indicators, and management strategy evaluation.
    • Strengthen compliance processes and make information on non-compliance public and continue to provide evidence of compliance with all IOTC Conservation and Management Measures in a timely manner.
    • Implement a 100% observer coverage requirement for at-sea transshipment activities, as well as other measures that ensure transshipment activity is transparent and well-managed, and that all required data are collected and transmitted to the appropriate bodies in a timely manner.
    • Increase compliance with the mandatory minimum 5% longline observer coverage rates by identifying and correcting non-compliance.
    • Implement a 100% observer coverage requirement – human and/or electronic – within five years for longline fisheries.  Adopt a 100% observer coverage requirement for purse seine vessels where it is not already required and require the use of the best-available observer safety equipment, communications and procedures.
    • Adopt effective measures for the use of non-entangling FAD designs as a precautionary measure to minimize the entanglement of sharks and other non-target species, and support research on biodegradable materials and transition to their use to mitigate marine debris.
    • More effectively implement, and ensure compliance with, existing RFMO bycatch requirements and take additional mitigation action, such as improving monitoring at sea, collecting and sharing operational-level, species-specific data, and adopting stronger compliance measures, including consequences for non-compliance for all gear types.
  • Ensure all products are traceable back to legal sources. Verify source information and full chain traceability through traceability desk audits or third party traceability certification. For fisheries without robust traceability systems in place, invest in meaningful improvements to bring the fisheries and supply chain in compliance with best practices.

1.STOCK STATUS

STOCK ASSESSMENT

Last updated on 16 January 2018

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).

IOTC
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 16 January 2018

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 16 Jan 2018

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 16 January 2018

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

Trends

Last updated on 16 Jan 2018

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

IOTC
Sri Lanka
Drifting longlines

Last updated on 28 March 2012

Trends

Last updated on 28 Mar 2012

According to official data from FAO, total catch of yellowfin tuna from Sri Lanka in 2007 was 40,397 tonnes, making this country the biggest yellowfin tuna producer in Indian Ocean, contributing to 13.35% of total yellowfin tuna landing in this ocean, followed by Spain (12.53%). Yellowfin tuna contributes more than 34% of total tuna catch in the country; the biggest one is skipjack with more than 50% of total tuna landing. Yellowfin tuna catch in Sri Lanka has shown the upward trend, though the production dropped significantly once in 2005, where the catch dropped by 30% from 35,512 tonnes to 24,887 tonnes due to the tsunami which was hit the country in December 2004.The 2004 Tsunami caused damage to one third of marine fishing fleet in Sri Lanka. Subsequent reconstruction funds have increased the fishing capacity to pre-tsunami level or far above the pre-2004 level.

According to the latest data from Department of Fisheries and Aquatic Resources (2009), yellowfin tuna landing in 2008 reached 47,590 tonnes. The main landing sites of yellowfin tuna are Matara (31.1%), Trincomalee (21.3%), Kalutara (14.1%), Negombo (10.6%) and Tangalle (7.9%) – See the Map of Districts in Sri Lanka .

Small scale gillnets and tuna long lines are the two main fishing methods used by Sri Lankan fishermen to target for tuna and tuna like fishes. There are over 3,000 boats are now engaged in tuna fisheries in Sri Lanka, with about 1,700 operating in offshore areas (IOTC 2007).“Multiday” operations are more frequent, producing a corresponding increase in effort. The average catch rate of the fleet operating in coastal waters is about 100 kg/fishing day, whereas in offshore waters, it ranges from 250 to 435 kg/ fishing day. Tunas and tuna-like species constitute 50 % of the total large pelagic catch in Sri Lanka (IOTC 1998).

Eventhough the main fishing gear is gill netting more than 40% of the fleet carry long lines specially during non-monsoon seasons. Other than this Sri Lanka owns 8 small sized (52ft) fresh tuna longliners targeted for yellowfin and bigeye. These boats operate throughout the year in EEZ of Sri Lanka and high seas. It is estimated that a further 26,000 tonnes of medium sized yellowfin and other tuna are landed by coastal tuna longline fishery operated with 20-40 km distance from the shore especially in the north west and northeast coasts of Sri Lanka. The fishery is conducted by 5-6 m long outboard engine day-boats. The reported species composition was dominated by 65% of yellowfin tuna (IOTC 2007).

With the issue of permits to fishing companies to land the tuna catch of longliners operated in international waters, a few local boat owners have started conducting tuna longlining at 50-100m depths, targeting on large, deep swimming yellowfin and bigeye tuna. Recently, a resource survey using longlining has been commenced.

2.MANAGEMENT QUALITY

MANAGEMENT

Last updated on 17 September 2018

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}. Discarding yellowfin tuna caught by purse seine's is prohibited (IOTC 2017).

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}. There are interim limit and target reference points in place for yellowfin tuna in the Indian Ocean (IOTC 2015).


 

Recovery Plans

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

IOTC
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.

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}.

IOTC
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

BYCATCH
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}.

IOTC
Sri Lanka
Drifting longlines

Last updated on 21 December 2018

Longline 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. 

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. During 2017, 34 olive ridley, 45 green, 7 hawksbill and 10 leatherback sea turtles were observed as incidentally captured in the longline fishery (Hewapathirana et al. 2018).

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 of circle 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}.

Other Species

Last updated on 17 December 2018

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).

IOTC
Sri Lanka
Drifting longlines

Last updated on 21 December 2018

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. In the longline fishery blue and silky sharks are the primary incidentally captured shark species. Overall, silky shark made up 68% of the reported shark catch during 2013. The longline fishery also catches billfish and other bony fish such as mahi mahi (Hewapathirana et al. 2018).

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. The Shark Fisheries Management Regulation of 2015 also prohibits the retention of oceanic white tip sharks, requires the recording of shark catches/discards in logbooks, among other things (Hewapathirana et al. 2018)

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.

IOTC
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.

Marine Reserves

Last updated on 05 Dec 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 .

FishSource Scores

Last updated on 17 September 2018

MANAGEMENT QUALITY

As calculated for 2017 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 2017 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 2017 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.

The score is 7.6.

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.

The score is 7.6.

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%.

ECOSYSTEM IMPACTS

Click on the score to see subscore

Click on the score to see subscore

Click on the score to see subscore

×

Bycatch Subscores

Sri Lanka instituted an observer program in 2014 on a pilot basis. During 2017, 13% observer coverage was reported on vessels over 24 m (IOTC mandate). However, the majority of the Sri Lanka's vessels are between 10-18 m in length and are considered too small to carry an observer (Hewapathirana et al. 2018).

Sea turtles are reported as incidentally captured in this fishery but the impact of this mortality to the entire population is unknown (Hewapathirana et al. 2018).

Bycatch of several species of sharks, along with billfish and bony fish occurs in this fishery and the impact of this mortality on their populations is unknown (Hewapathirana et al. 2018).

Sri Lanka has some measures in place to address bycatch. These include requlations for sea bird mitigation and safe release of turtles and voluntary use of circle hooks. Several species of sharks are prohibited from being captured but there are no bycatch mitigation measures in place for these species (Hewapathirana et al. 2018).

×

Habitat Subscores

There is some information on the timing of the fishery on the habitat (Chuenpagdee et al. 2003).

Some priority habitats have been identified and there is some reliable information on their location and status (IOTC 2017).

The fishery does not reduce the function of the habitat.

Measures are not in place to protect the habitat but this gear has minimal impact to habitats (Chuenpagdee et al. 2003).

×

Ecosystem Subscores

There is some information available to determine the impacts of the fishery on the ecosystem structure (IOTC 2017).

There is some availalbe information allowing for characterization of the ecosytem (IOTC 2017).

The fishery likely disrupts the ecosystem but the full impact is unknown.

There are some measures in place to manage the impact to the ecosystem (Hewapathirana et al. 2018).

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

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).

 

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Fishery Improvement Projects (FIPs)

SELECT FIP

Access FIP Public Report

Progress Rating: C
Evaluation Start Date: 18 May 2018
Type: Basic

Comments:

FIP is less than a year old but making stage 3 progress.

1.
FIP Development
Mar 18
2.
FIP Launch
May 18
Dec 18
3.
FIP Implementation
Jun 19
4.
Improvements in Fishing Practices and Fishery Management
Verifiable improvement in policy/management and fishing practices
5.
Improvements on the Water
Verifiable improvement on the water
6.
MSC certification (optional)
MSC certificate made public

Certifications

Marine Stewardship Council (MSC)

No related MSC certifications

Sources

Credits

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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