Two important tuna research trips have gone ahead in the Western and Central Pacific Ocean (WCPO) this year, although the research programs and the routes had to be curtailed dramatically.
Both programs, which are run by the Pacific Community (SPC), were cut back to comply with regional practices put in place to prevent the transmission of COVID-19.
For the Pacific Tuna Tagging Programme, scientists continued routine tagging of tuna and tested new sampling methods that will help scientists analyse the structure and behaviour of tuna populations.
The research was conducted in the high seas and the exclusive economic zone (EEZ) of the Kiribati groups of Line Islands and Phoenix Islands.
This year’s cruise was originally to have focused on understanding more about the habit of tuna to gather around drifting fish-aggregating devices (FADs). It was to have been conducted in waters around Tuvalu, which have one of the highest densities of drifting FADs in the WCPO.
The tagging cruise left from Honolulu, Hawaii, in mid-August, and returned to the same port in early October, staying clear of any other ports. Mr Leroy and Dr Allain said that protocols to protect Pacific Islands people from COVID-19 meant that, before the research vessels could depart, the crew and scientists had to stay isolated for 14 days and return negative test results to the disease.
Mr Leroy said that, since the Pacific Tuna Tagging Programme began in 2006, about 455,000 tuna had been tagged. If SPC tagging campaigns carried out since the end of the 1970s were included, the number was more than 800,000. On the 2019 cruise, researchers tagged nearly 17,000 tuna.
Second study to develop better ways to sample small marine animals
Bruno Leroy and Valérie Allain also reported on a second SPC research cruise, which was also curtailed to comply with COVID-19 rules.
The SPC’s scientific team conducted a four-day trial to develop a new sampling method to collect micronekton from the surface of the ocean to a depth of 600 m. (Micronekton are marine animals such as fish, crustaceans, jellies and squids that measure 2–20 cm in length. They are the main source of food for seabirds, tuna and marine mammals.)
As the research vessel Alis is based in New Caledonia, the trial was conducted inside the country’s EEZ.
The original cruise planned for this year in the waters of New Caledonia, Solomon Islands and Federated States of Micronesia has been postponed until 2021. It is part of a long-term program to study the ecosystem of the open oceans in the Western and Central Pacific.
One of the most important tools in understanding the biology and environment of tuna in the Western and Central Pacific Ocean is a bank.
This particular institution, the Pacific Marine Specimen Bank (PMSB), has been slowly building its revenue of research currency – muscle, organ and bone samples, stomach contents, photographs, and radiographic images – since 2000.
It also collects samples from other large, oceanic species such as marlin and swordfish that are also economically valuable.The PMSB is managed by scientists in the Oceanic Fisheries Programme of the Pacific Community (SPC). The datasets held in the bank help the scientists understand the world of tuna. Their knowledge forms part of SPC’s annual assessments of the state of health of tuna populations. In turn, the assessments are used to manage tuna fishing in the region.
Specimen banks are important because they throw light on our understanding of current situations – and because scientists in the future can use the same samples to find answers to new questions or to ask the same questions using new techniques or research tools.
One of the challenges the staff of PMSB face is ensuring that samples, which are collected all over the Western and Central Pacific Ocean, are kept in prime condition until they get to a permanent storage facility. Part of the scientists’ work is to prepare some samples to make it easier to transport them to analysis laboratories outside New Caledonia.
Much care goes into getting, storing, and transporting samples so they can be used for immediate research and analysis, and also in many years’ time.
This usually means that they have to be kept cold enough. Many samples can be kept at –20°C; however, those used in genetic analysis must be kept at –80°C. Freezers of the second kind are difficult to come by, and expensive to run.
Other tissue must be preserved in formalin and then transferred into ethanol.
The nine cubic metres of freezer space at the laboratory at SPC in Noumea is now too small to contain the growing collection. Although there are plans to enlarge it, research partners are also helping to house pieces of the collection in other parts of the region.
And SPC has funded the purchase of freezers in the main fishing ports in the region to that samples can be stored safely until they are transferred to their final destination.
In April, the PMSB contained nearly 120,000 samples collected from 34,000 specimens. Some national observer programs have participated in collecting samples for the bank since 2002.
Note: post updated 6 July 2020 to correct a spelling error.
HONIARA, 27 February 2020 – Solomon Islands and Fiji are expected to benefit from the One Ocean Hub (OOH) research program that recently began work in the Pacific.
The two Melanesian nations are among the initial countries that have been identified as recipients of the worldwide program that focuses on equitable and inclusive governance of the oceans and ocean conservation.
The University of South Pacific (USP) is the Pacific partner for OOH. The project manager for the hub at USP is Mr Viliamu Powell.
He says the Pacific hub team is made up of the academics Professor Derrick Armstrong, Professor Jeremy Hills, Professor Matthew Allen, Associate Professor Ann Cheryl Armstrong, Associate Professor Gilianne Brodie, Dr Morgan Wairiu, and Associate Professor Pierre-Jean Bordahandy. These academics are known as co-investigators (CIs).
Input from locals essential
“At this stage, the OOH team in the Pacific is in the work package zero (WP0) phase, which will be completed by April,” Mr Powell said.
“During the WP0, the team is working with stakeholders in Fiji and the Solomon Islands to identify key research challenges that affect vulnerable communities that depend on the ocean.
“It is important that these issues are drawn directly from the stakeholders and is not biased by preconceived notions of what constitutes a development issue.”
The USP CIs facilitated a three-day workshop in early February with stakeholders from Fiji and Solomon Islands. Participants came from government, universities, civil society organisations, and non-governmental organisations.
This forum built on a workshop held last December. That event provided insights into aspects of oceanic research that could be addressed through the OOH research. Of particular interest are gaps and intersections.
Mr Powell said the February workshop was used to refine discussions from the first workshop and, with stakeholders, to identify and develop research strategies that are appropriate for the Pacific.
“The major highlights came with the presentations from the different speakers, as they all provided valuable insight. Some of the key messages came from the principal of the Pacific Theological College, Reverend Professor Upolu Vaai, from fisheries law expert Dr Transform Aqorau, and Dr Cresantia Frances Koya-Vaka,” Mr Powell said.
“Reverend Professor Upolu reminded all the participants that it was important to think of research through a multi-dimensional lens, and how, in the Pacific, this was something that we already practise through our ways of communal living and our relationship with the land and sea.
“As for Dr Transform Aqorau, it was a pleasure to have such a highly respected academic and consultant contributing to the discussions to frame research questions in the Pacific.
“Dr Transform spoke of his experience in regional work through his time at the Parties to the Nauru Agreement (PNA), the Pacific Islands Forum Fisheries Agency (FFA), and the Pacific Islands Forum Secretariat (PIFS), and his work within the civil service in the Solomon Islands.
“Through all of the work that researchers do it is most important to think of our Pacific people,” Mr Powell said.
“In her presentation, Dr Cresantia Frances Koya-Vaka reinforced the need to protect local people from exploitation. The rights and property of Pacific Islands’ indigenous peoples should always be considered when trying to conduct research in the Pacific.”
Chasing greater wellbeing and better livelihoods
Mr Powell said that, over the next four years, it was hoped the OOH USP team would provide tangible outputs that benefited specific communities in Fiji and Solomon Islands so they could improve their wellbeing and livelihoods.
“It is important that what is seen as beneficial is derived from the communities directly, so the research project will aim to address these areas. We hope that this initiative will be the beginning, and the results we obtain from the communities we work with can be replicated in other Pacific nations,” Mr Powell said.
Dr Transform Aqorau said that another purpose of the workshop was to talk about possible areas that could be supported in Fiji and Solomon Islands.
He was invited on the basis of his work in fisheries and, more recently, engagement in the local community around resource issues.
At the workshop, he shared his experience about governance and regime building for fisheries in the region.
“We had representatives from the Solomon Islands, Fiji, USP, PIDF, Pacific Islands Forum Secretariat, Pacific Theological College, and from Kenya, France, and some civil society groups in Fiji,” Dr Transform said.
“This was actually the second framing workshop to identify what can be done, and so trying to narrow it down.”
He added that the benefits of the program to the Pacific Island countries was about working and carrying out research around areas to support local communities and increase their engagement to improve community well-being.
“Ultimately, the project will have to be embedded in both the government and [in the] local communities where the project will be situated,” Dr Transform said.
He said the project is unique in that it has three regional geographic focus areas: Africa, the Caribbean, and the Pacific.
However, the challenge in the implementation of this kind of funding is to locate it in a local context while still meeting the higher-level need for trans-disciplinary results that donors want.
USP-based Dr Morgan Wairiu said that Solomon Islands and Fiji were already engaged in the development of the research plan and its implementation.
“These research tools or methodology can be used by communities and government to bring about sustainable development of ocean resources,” Dr Morgan said.
Findings will inform development
Meanwhile, Rosalie Masu, the Deputy Director of the Inshore Fisheries Division, who represented the Ministry of Fisheries & Marine Resources (MFMR) of Solomon Islands, said her country was very fortunate to be identified with Fiji to be part of the OOH initiative.
“The benefit of this research is that the findings will be used to inform development decisions for Solomon Islands,” Mrs Masu said.
“But the government must also be inclusive and part of the discussions in formulating the research designs.”
About the One Ocean Hub
The One Ocean Hub is an independent program for collaborative research for development.
Its vision is for ocean governance to become integrated worldwide to better protect the interconnected environments and lifeforms of the oceans, and so communities that rely on the ocean remain connected to it economically and culturally.
The project is funded until February 2024. It involves scholars from different fields of research at 22 universities and research centres in the United Kingdom (UK), South Africa, Ghana, Namibia, Kenya, the South Pacific, and the Caribbean. The hub is led and hosted by the University of Strathclyde, in Glasgow, UK. It is funded by UK Research and Innovation through the Global Challenges Research Fund.
OOH seeks to address specific challenges that vulnerable coastal communities face. The research is being conducted under five programs, and researchers intend to share knowledge between the regions to help vulnerable communities be involved equitably in decision-making about how the oceans’ resources are both used and protected.
At the core of their research is one of the elements at the heart of a heating planet: carbon.
By tracing two of the most abundant forms of carbon, the isotopes carbon-12 and carbon-13, they were able to show that a significant amount of global heating is caused by human activities rather than natural processes.
They also found that several other factors also influence the amount of different carbon isotopes in tuna.
Scientists find evidence of changes in the food chain
One of the most important happens at the start of the food chain, with a group of plankton known as phytoplankton, which use sunlight and carbon to make the energy they need.
The scientists showed that the abundance of different kinds of phytoplankton has changed in the past 15 years, directly as a result of the burning of fossil fuels. They also showed that the proportion of carbon-12 and carbon-13 available changes the kinds and abundance of phytoplankton. These changes don’t stop here, but alter the kinds and abundance of animals, including tuna, all the way up the food chain.
Numbers of some phytoplankton are shrinking, and this too is affecting the abundance and location of tuna.
The change in the balance of phytoplankton is made worse by another effect of climate change: ocean stratification. Surface and deep waters of oceans now mix less, and that fewer nutrients are stirred up and made available for plankton to consume.
The research also showed changes in how quickly phytoplankton grow.
The scientists traced two forms of carbon
The research involved scientists from several fields. Among them was Valérie Allain of the Pacific Community (SPC).
The scientists took 4,500 samples of muscle from albacore, bigeye and yellowfin tuna over 15 years, from 2000 to 2016, from the Pacific, Indian and Atlantic Oceans. They found that changes were most pronounced in the Pacific Ocean.
They traced two forms of carbon, carbon-12 and carbon-13. This is possible because each isotope each has a different weight and also behaves slightly differently.
Carbon is found naturally in living things, and in the air, land and water. It is also present in coal and oil, and when these burn, carbon-12 is released into the atmosphere.
More than 90% of atmospheric carbon is absorbed by the oceans. From there, it enters the food chain, being taken up by plankton and passed on to each predator up the chain, until it ends up in tuna, along with other forms of carbon such as carbon-13.
Reporting on their findings in the most recent issue of SPC’s Fisheries Newsletter, Valérie Allain and another researcher, Anne Lorrain, said that the data will be “of inestimable value” in projecting the effects of climate change on the health and quantity of seafood, and in validating modelling. This is because they collected so much data over such a long time and a very large geographical area.
Their research makes much more certain that humans do affect the environments and inhabitants of the open oceans.
More than 16,600 tuna were tagged in a recent scientific tagging expedition in ocean generally north of Papua New Guinea.
The voyage targeted skipjack tuna, which makes up 70% of the volume of tuna caught in the Western and Central Pacific Ocean (WCPO).
Tuna tagging helps the Western and Central Pacific Fisheries Commission (WCPFC) and national fisheries managers assess numbers of tuna. The assessments are used to set catch limits.
This voyage was conducted largely in the exclusive economic zones (EEZs) of Papua New Guinea, Solomon Islands, Palau, and Federated States of Micronesia, with a little time spent also in two pockets of high seas.
In its most recent fisheries newsletter, SPC reported that fisheries authorities in PNG, Palau and FSM provided research permits and gave support to the research being done in their EEZs.
An average of almost 450 tuna were tagged and released each fishing day. Most – 93% – were skipjack, the rest being yellowfin (6%) and bigeye (1%). Most came from free-swimming schools (i.e. the tuna were not caught near fish-aggregating devices, or FADs).
Some fish were implanted with what is known as an archival tag, a physical device which must be inserted using small surgery and a very fast turnaround – no more than 30 seconds – so that the tuna doesn’t become too stressed and lacking in oxygen.
SPC reported that it expected some of the tuna tagged in this way would be recovered and would provide good data on the behaviour and movement of the fish.
The agency also reported that some tuna were injected with strontium chloride, a slightly radioactive salt that becomes incorporated into a part of the tuna’s skeleton known as the otolith (or ‘ear stone’). As the fish grows, scientists can use the mark left by the strontium chloride in the otolith to estimate how old the fish is. (Otoliths help fish to balance and to understand how fast they are swimming.)
To conduct the tagging cruise, SPC chartered a pole-and-line vessel from Noro, in Solomon Islands.
This was the fifth western Pacific tagging cruise, and it lasted from July to September 2019.
Tuna tagging has been carried out regularly since the Pacific Tuna Tagging Programme ran its first voyage in 2006.
A newer method of assessing bigeye tuna stocks in the Western and Central Pacific Ocean has resulted into a more positive appraisal of the population.
In 2014, the key scientists responsible for assessing the stock published new studies suggesting bigeye tuna stocks were down to 16 percent of the original population – a critical level.
Now the same scientists have completed much more detailed studies which suggest bigeye tuna are at 32 percent of their potential population.
Dr John Hampton told Pacific journalists here at the meeting of the region’s tuna management body, the Central and Western Pacific Fisheries Commission, that the latest assessment indicated a more productive stock that is more resilient to fishing that had previously been estimated.
Hampton, one of the marine biologists of the WCPFC Scientific Committee, said he and his colleagues have changed the way they measure the population and now have a different estimate on population size.
New research indicates bigeye grow and mature faster than they previously thought and do not grow as big.
The work is based on detailed data collected across the Pacific since 2011.
Analysis of the data was only completed early this year.
The results are a ‘profound’ change according to Dr Hampton and there is still much uncertainty, so in order to determine whether the big eye tuna stocks have decreased or increased, they need to keep studying the population using their new methods for longer period.
“I should say when we do these assessments we don’t just do one analysis using one formulation of the dynamics, we use a whole bunch of stock assessment models that try to capture all the different areas of uncertainty that we have throughout the stock so that we can capture and present what we hope is an honest assessment of the stock so that we can present a picture of what we know and what we don’t know,” Hampton said.
The current fishing rules for bigeye are contained in a resolution of WCPFC called the Tropical Tuna Measure, which expires at the end of the year.
Representatives from over 30 countries here at WCPFC14 in Manila have the job of deciding what will replace the Tropical Tuna Measure.
The Scientific Committee has recommended that there be no increase in bigeye mortality.
Forum Fisheries Agency (FFA) Director General James Movick too, warns that even with the more optimistic stock assessment, there is still no room for complacency when it comes to managing the stocks,
“It would be dangerous to suggest that given the current state of the stocks, maybe we can permit more fishing, particularly for bigeye,” Movick told reporters here over the weekend.
“The FAD closure measures agreed to by Pacific countries, even at an economic cost to them, have contributed to improvement in the stock status, and our general position is that we should — particularly at this early stage–call for caution,” he said.
Wez Norris, FFA Deputy Director General in today’s briefing with reporters said that there are some suggestions from (WCPFC) member nations that because of the tuna stocks positive assessment, fishing measures can be relaxed.
“I think the main concern for us ..is some fairly generous interpretations of the science in terms of how far we can relax existing measures.’ Norris said
The scientists are expected to deliver a more definitive report on their new studies next year.