WCPFC’s 16th Scientific Committee (SC16) was held virtually from 12–19 August 2020. During this meeting new WCPO bigeye and yellowfin stock assessments were presented by the Secretariat of the Pacific Community (SPC), indicating that both stocks remain healthy.
The previous full stock assessment for bigeye was conducted in 2017. It indicated a positive change in WCPO bigeye stock status to ‘healthy’ from ‘overfished’, with overfishing occurring. For the 2020 assessment, median values of relative recent spawning biomass (2015–2018) and fishing morality (2014–2017) indicate that the bigeye stock remains not overfished (with 100% probability) and likely continues to not be experiencing overfishing (with 87.5% probability).
However, levels of bigeye fishing mortality and depletion differ among the nine regions used in SPC’s stock-assessment models, with higher impacts in the four tropical regions, particularly on juvenile bigeye. Hence, overall bigeye stock status is buffered by lower catches in the temperate regions.
Similarly, the 2020 stock assessment indicates that the WCPO yellowfin stock is not overfished, nor subject to overfishing (both with 100% probability). Like bigeye, yellowfin exploitation is higher in tropical regions where fishing effort is concentrated by the equatorial purse-seine fishery and ‘other’ fisheries (e.g. pole-and-line and handline vessels operating in Indonesia); there is low yellowfin exploitation in temperate regions.
Hence, for both bigeye and yellowfin, SC16 recommended that WCPFC17 continue to consider management measures that reduce fishing mortality from fisheries that take juveniles (i.e. purse-seine fishery) to increase bigeye and yellowfin fishery yields and reduce any further impacts on spawning biomass in the tropical regions.
SC16 also recommended that a precautionary approach be maintained, with bigeye and yellowfin fishing mortality kept at a level that maintains spawning biomass at 2012–2015 levels until the Commission can agree on appropriate target reference points (i.e. the optimal level of spawning biomass or fishing mortality that ensures long-term sustainability of the stock).
The WCPO continues to be the only ocean where stocks of the four key tuna species – skipjack, yellowfin, bigeye and albacore – are deemed to be in a healthy state.
Majuro – Despite millions of pounds of tuna transhipped through Pacific island ports, nobody has a precise count of the tonnage.
The entire system for both industry and island fisheries managers revolves around estimates of the tonnage – a deficiency the Marshall Islands Marine Resources Authority (MIMRA) is attempting to remedy.
“Knowing how much fish a purse seiner really caught is not an easy task, not for industry or for the authorities,” said Francisco Blaha, the Offshore Fisheries Adviser at MIMRA in Majuro.
“Traditional scales don’t work on board, and getting fish into low temperatures as soon as possible is fundamental for food safety and quality particularly when you have a big set of over 100 tons in the water.”
As a result, tuna boat captains and fisheries observers work on estimates. “While they are very good, it is still an estimate,” said Mr Blaha. “Only once the fish is unloaded for ‘weigh in’, generally at the cannery, or sometimes before containerisation do we get to know the real verified weights.”
But, he added, this often happens months after the tuna is caught, and the catch tonnage data may never actually be seen by the island fisheries managers.
Mr Blaha, an experienced commercial fisher whose position in Majuro is supported by the New Zealand Ministry of Foreign Affairs and Trade, said this has negative implications for stock assessments and fisheries assessments, but also financial impacts for the fishing crew.
Gaining accurate weights is good for everyone since “weights are fundamental and benefit all sorts of fisheries decision making”, said Mr Blaha, who ticked off those interested in catch weights: crew and skipper who are paid partly based on the volume of fish caught; vessel managers who deal with profitability and insurance issues; carrier vessels that deliver the tuna to canneries; and scientists and regulators who generate stock assessments and advice about allowable catch levels. “Quite simply, the more accurate the data, the better decision making,” he said.
Majuro is currently the busiest tuna transhipment port in the world, with over 400 purse seiners annually transshipping about 300,000 tons of tuna. The process of transferring between 800 and 1,700 metric tons of fish from purse seiner to carrier vessel can take up to a week and involves putting the frozen fish in nets and hoisting them into the carrier from the deck of the purse seiner.
MIMRA science and boarding officers saw transhipment operations as an excellent opportunity to verify the weights caught by purse seiners by weighing each the of the nets with frozen fish as they are transshipped using hanging scales attached to the hooks of the cranes used during the operation.
MIMRA gained support from the Forum Fisheries Agency (FFA) and Pacific Community (SPC) to research the feasibility of the concept and to evaluate what type of hanging crane scales will do the job best.
Last month, MIMRA started what is believed to be a world-first research program to determine the best system for weighing fish coming off a purse seiner to a carrier vessel. A team composed of FFA, SPC and MIMRA people launched the testing of four different types of remotely operated electronic crane scales during the transshipment of a Marshall Islands flagged tuna vessel.
Mr Blaha said they evaluated each model against attributes such as precision, robustness and ease of use, battery performance, recyclability, and price and connectivity.
“The results will benefit not only the Marshall Islands but the whole region as there is transshipment activity in Kiribati, Federated States of Micronesia, Tuvalu, Papua New Guinea and Solomon Islands,” said Mr Blaha.
The work is expected to continue in 2020 with the general aim of standardizing the use of crane scales for monitoring the weights of all tuna transhipped in the region. It has additional benefit for management and data acquisition for port monitoring operations, he said.
It said all four species that are economically important in the region – skipjack, South Pacific albacore, yellowfin and bigeye – are being fished sustainably.
In the parlance of the report, “none is being overfished, and overfishing is not occurring”, although there was “no room for complacency” in how fish stocks are managed because all four species continue to decline overall.
The abundance of a species is estimated against a benchmark, called a target reference point (TRP), which is a desirable level of stock needed to maintain the healthy functioning of the species, the environment it lives in, and the sustainability of fishing.
The report card said that numbers of skipjack tuna are above the target reference point (TRP) for that species. TRPs are being developed for the other three species.
The report noted that the value of tuna fishing to the region is increasing, and had passed the target for 2020.
Local employment in the tuna industry was also increasing, and was on target to meet the 2023 target.
Japanese fisheries officials heard from their international counterparts about methods for incorporating more data into their fisheries science and management at a recent workshop in Tokyo.
The workshop,“New Resource Management Based on Data Innovation: Current State of the United States and Future Vision of Japan,” took place at the Japanese Ministry of Agriculture, Forestry, and Fisheries building on 7 March. The event was co-sponsored by the Fisheries Agency, the Fisheries Research and Education Organization, and the U.S.-based non-governmental organization Environmental Defense Fund (EDF).
Japan’s Fisheries Reform Act, the first major reform of Japan’s fishing laws in 70 years, was approved in the Diet at the end of last year. The law will move Japan from a total allowable effort (TAE) system – in which the number, size, and period of operation of fishing boats, and the types of gear allowed, are regulated – to a total allowable catch (TAC) system with vessel quotas for most species.
In comparison with other countries, Japan has so far set a TAC for only a few species. Those include saury, Alaska pollock, sardines, mackerel, Southern mackerel, horse mackerel, squid, and snow crab – and recently for juvenile bluefin tuna. But with the reform, Japan will have to set TAC for many more species and fisheries, some of them data-poor, and also monitor and enforce the TACs. To accommodate the move, the government is planning an expansion of the country’s stock assessment system and an expansion of the use of data from fishing operations.
Masanori Miyahara, president of the Japan Fisheries Research and Education Agency (FRA), said under Japan’s current slow paper-based system, scientific assessments and quotas are made based on two or three-year old data. That leads to complaints from fishermen that stock assessments do not reflect what they are actually seeing when they fish. When a stock is recovering, this results in a TAC that is too low, and so it is bad for the fishermen. He also said that computerization of survey and landing data is becoming a global standard and may be required in future for sustainability certification schemes. Japan may find itself at a disadvantage in global markets if it cannot meet these standards, Miyahara said.
Guest speakers at the workshop included Dorothy Lowman and Shems Jud. Lowman is a U.S. commissioner of the Western and Central Pacific Fisheries Commission (WCPFC), though she did not speak in that capacity at the meeting. In the past, she organized a national workshop on data modernization/electronic monitoring, and played a leadership role in the Pacific Fishery Management Council’s decision-making on groundfish. Her main activity now as part of the leadership team of the Net Gains Alliance, which is an initiative to support U.S. data modernization. Shems Jud is deputy director for the Pacific region for the Environmental Defense Fund (EDF), who was involved in changes to the management and data collection systems in the U.S. West Coast groundfish fishery.
Lowman explained the steps involved in setting up an electronic monitoring (EM) program, including a sample timeline, with special emphasis on involving all of the parties involved. For example, teaching some fishermen how to use the system, and then getting them to train others was effective. Lowman emphasized the benefit of not putting too much detail in the regulations, but rather referring to a vessel monitoring plan (VMP) for the details, in order to keep some flexibility.
“It takes two years to change a regulation,” while a VMP can be changed more easily, she said.
Jud reviewed the experience of the U.S. West Coast groundfish fishery, which adopted an individual transferable quota (ITQ) system in 2011. This required shipboard monitors to enforce the quota and ensure operators were not discarding bycatch. But using shipboard monitors on all vessels was expensive and problematic, Jud said. For example, if observers were unavailable, the vessel could not fish. And if an observer was scheduled and paid for, operators felt pressure go out even if conditions became dangerous. For smaller vessels, the additional person meant the loss of space for a crewmember. As a result of these problems, the Pacific Fishery Management Council voted to allow camera-based electronic monitoring (EM) systems in some fisheries from 2017. Under the “optimized retention” approach adopted by the council, fishermen’s logbook entries are the primary data source, and they are checked against the videos by authorized third-parties. Jud noted that due to success in rebuilding stocks, environmental groups that were previously critical of the industry are now even involved in joint marketing.
“That fishery is hard to attack now,” he said.
There has been movement toward utilizing artificial intelligence (AI) for reviewing of the footage and the Japanese would like to learn about and employ such systems. The Japanese side is also hoping to digitize stock assessment data, such as having fishermen enter the catch on a tablet computer on the trip to shore instead of a paper based system that is slowly compiled and assessed. The goal is to use electronic reporting (ER) to get stock assessments that reflect real-time conditions.
The panelists in the workshop faced audience questions over concerns regarding the confidentiality of data, since fishermen like to keep their favorite spots a secret. Additionally, there were many questions for Lowman from the Japanese side about who owns and has access to the data, especially from vessel monitoring systems (VMS) that show vessel movements.
As the average age of Japanese fishermen is over 60, many questioned whether they could master the input of catch data by tablet computers, due to the fact that many older Japanese have low computer literacy. Everyone had a laugh when a video that was to be played at the workshop could not be made to run due to technical issues. Complicated modern technology was blamed.
Just five of the world’s 19 commercial tuna stocks have earned a passing “Principle 1” score from the Marine Stewardship Council, the International Seafood Sustainability Foundation (ISSF) notes in a report issued Friday.
Principle 1 is the standard for operating in a way that does not deplete the fishery.
Though The South Pacific albacore Principle 1 score has improved thanks to further progress by the Western and Central Pacific Fisheries Commission on this stock’s harvest strategy work plan, two other stocks have seen their overall Principle 1 scores worsen, ISSF noted. The eastern Pacific bigeye fishery saw its score decline “due mostly to uncertainties in its latest stock assessment”, while the Atlantic yellowfin tuna dropped “due to weak tools in place to control exploitation that may be hindering its rebuilding plan”, the group said.
The time is ideal for the Western and Central Pacific region to put in measures to ensure robust tuna stocks for the future.
The most recent assessments on the tuna stocks in the region by the Pacific Community (SPC) show they are all in the green zone, with fishing activity at sustainable levels.
Bubba Cook, Western and Central Pacific Tuna Programme Manager at WWF (World Wide Fund), says taking the right measures will help the region address issues that other regions have failed to address, notably depleted stocks.
“We have a chance to get management right. The resources are robust and stock levels are in the green zone,” Cook says. “We don’t want to end up like other places around the world where they have seen the stock collapse and have to talk about recovery.
“These countries have seen the economic consequences. We are in a really good position to sort out problems other regions have not addressed successfully.”
The state of tuna stocks
Assessments of the four major tuna stocks have been completed recently: yellowfin and bigeye tuna in 2017, skipjack in 2016 and albacore in 2015.
Dr John Hampton, chief scientist and deputy director of SPC’s Division of Fisheries, Aquaculture and Marine Ecosystems (FAME), says they usually assess the stock level of at least one species every three years in order to evaluate different management strategies.
According to the assessment, skipjack tuna stock stands at 58 per cent, yellowfin at 33 per cent, albacore at 40 per cent and bigeye tuna at 32 per cent. Pacific bluefin is at historic low at 2.6 per cent.
“When we say the stock level is at 40 per cent for albacore, it means fish are at a level 40 per cent of what the stock would have been if we never had any fishing,” he says.
“At the moment, skipjack tuna, yellowfin and bigeye are not overfished, and nor is overfishing occurring.”
A new understanding of the growth rates of bigeye tuna meant that the scientific assessment of these stocks changed last year. The assessment of bigeye tuna was amended from ‘overfished’ to ‘not being overfished’.
“It’s quite a big level of depletion before we say it’s overfished, which means that these stocks are pretty resilient,” he says. “A stock is not classified as ‘overfished’ until the spawning population is reduced to less than 20 per cent of the unfished level.”
A rebuilding plan for Pacific Bluefin has been implemented by the Northern Committee of the Western and Central Pacific Fisheries Commission (WCPFC). The initial target is to increase the spawning biomass to the 20% level. This has involved catch restrictions particularly on those fisheries catching very small Pacific bluefin tuna (PBF). The International Scientific Committee for Tuna and Tuna-Like Species in the North Pacific Ocean has responsibility for assessments of PBF.
Future forecast on tuna stock
In Dr Hampton’s view, the main scientific advice and current management aims to keep things stable at current levels. In case of albacore, he says they would like to increase the size of the stock “a bit”.
And in order to achieve that, the catch has to be reduced. Finding agreement is a difficult issue for the FFA and the member countries.
“The problem with the albacore fishery is an economic problem rather than a biological problem”, he says. “They are sustainable as a stock in the long term”.
Some of the longline boats based in Pacific island countries face difficulty in being profitable at the current catch rates and economic conditions that prevail in the fishery.
Costs are high, but prices are low and so are catch rates. The poor catch rates are a consequence of the larger fish being depleted and they are the ones normally caught by longline fishers.
To make the fishery more profitable, fishing nations would have to allow the larger fish time to develop and that means reducing current catch rates. It has proved difficult to reach agreement on this.
“But if you get a better price for the albacore than is currently being paid there is less of a need to reduce current levels of catch,” Dr Hampton says.
“The problem with albacore is that fish are sold to canneries at $2.50 to $3 a kilo, whereas if fishers sell it at a fresh fish market they get three times the (cannery) price. These markets do exist in places like New Caledonia and Tahiti, and so the longline fisheries based there can make a good profit.”
Politics sometimes clashes with good management
Bubba Cook says it is important to keep politics out of management measures if tuna stock are going to remain sustainable in the future.
“The use of harvest strategies or harvest control rules based on a particular benchmark takes politics out of the issue,” he says. “It allows science and actual policy and management perspectives to set the limits.”
This will give the region a process that actually responds to the biological and economic conditions in fisheries.
“When you get some of the politics out of fisheries, you can actually see better management of our fisheries,” Cook says.
Mexico and Japan have already breached their bluefin fishing limit for the second year in a row, despite strict quotas, said Pew Charitable Trusts.
Pacific bluefin is worth nearly $1 billion at the final point of sale, but it has been severely depleted over the years, and now just sits at 2.6% of its historic level, the charity said.
In September 2017, countries agreed to a rebuilding plan for the species. However, “there is little room for error, and the quota overages will continue to hurt recovery”, Pew said.
A new stock assessment for Pacific bluefin will be released this summer, and it will give fishery managers a time to consider if the recovery plan is working, and how much work must still be done to rebuild the species.
But if countries continue to stretch the limits, there is little chance for success, and the species will remain in serious jeopardy, Pew said.
“Pacific bluefin tuna can’t catch a break. Mexico, one of the leading fishing nations for this severely depleted species, officially exceeded its 2018 quota just four months into the year on May 3,” said Jamie Gibbon, an officer on Pew’s global tuna conservation campaign.
“If nations are unable to enforce the rebuilding plan and show that they are honestly tackling overfishing, the idea of an ocean-wide commercial fishing moratorium may have to be revisited as the last ditch option to save the species,” Gibbon said.