Nav: Home

Safeguarding the world's largest tuna fishery

October 01, 2019

Understanding the impact of modern fishing techniques is critical to ensure the sustainability of the Western and Central Pacific Ocean (WCPO) tuna fishery - the largest tuna fishery in the world that accounts for 55% of the total tropical tuna catch and provides up to 98% of government revenue for some Pacific Island nations.

Multiple agreements have been signed by Pacific island countries and territories to maintain the sustainability of this important ocean resource. However, the advent of Fish Aggregating Devices (FADs) and their impact on fishing efficiency over the past 20 years has added a large unknown to the management required to maintain the sustainability of this key fishery into the future.

Researchers from The Pacific Community's Oceanic Fisheries Program (SPC) and the ARC Centre of Excellence for Climate Extremes have recently published two papers that used a combination of records from captains and scientific observers, FAD tracking data, ocean models and cutting edge simulation methods to reveal for the first time the trajectories and potential impact these FADs may have on fisheries and the island nations.

"Around 30,000-65,000 FADs are released every year in this region but we have very little understanding of where they ended up, how they are being used, and the impact this has had on coastal areas and the overall catch of the fishery," said Dr Lauriane Escalle, a fisheries scientist at SPC.

"While we know FADs make fishing more efficient, allowing fishing vessels to use less fuel and reduce fishing effort, there are unanswered questions around potential overfishing, impacts on bycatch species, ghost fishing and reef damage caused by FADs washing up on coral reefs and islands."

Aside from catch data and ocean models, modern FADs themselves played an important role in helping the researchers get their answers.

Traditional FADs work because ocean-going species, like tuna, tend to aggregate around floating objects like floating logs. Why they do this is still not fully understood but fishers have long known this fact and taken advantage by releasing bamboo rafts into the ocean - the world's first FADs. Over time commercial fishers added old ropes and nets to slow the drift through the ocean.

Today, FADs are high-tech buoys with solar-powered devices that record the position, scan the ocean below to estimate the number of aggregated fish and transmit all this information to vessels via satellite. This technology opened the door to detailed observations of FAD life history while they drift across the Pacific.

Combining this real-world information with catch data and cutting-edge simulations based on ocean models allowed the researchers to examine the dynamics of FAD connectivity and to test different hypotheses explaining the high number of FADs beaching incidents in some areas. This key information could significantly add to the management of the Western and Central Pacific Ocean tuna fishery and the exclusive economic zones within it.

The studies found that:
  • More than 2000 FADs wash up on beaches and coral reefs every year.

  • Up to 6000 FADs fished on in the WCPO had drifted in from another fishery in the Eastern Pacific Ocean, which has different management systems;

  • FADs spent more time in the exclusive economic zone of Tuvalu and the Solomon Islands than any other part of the fishery.

  • The highest number of FAD beaching events occurred in the Solomon Islands, Papua New Guinea and Tuvalu. This was more the result of ocean currents than where the FADs were deployed, making the management of this issue more difficult.

  • Kiribati, located along the equator, experienced a high number of FADs drifting through their waters, alongside significant levels of beaching, as a result of where fishers deployed FADs.

  • Results from these studies will help effectively manage tuna resources, through measures on the number and location of FADs deployments; the use of biodegradable FADs; programs to recover lost FAD before reaching sensitive areas; and more research on FAD impact on tuna and bycatch populations.
"Access to this unique regional database of FAD tracking data by fishing companies and managers allowed us to not only validate ocean models but also to test different deployment hypotheses using millions of virtual FADs," said Dr Joe Scutt Phillips, another fisheries scientist at SPC.

"This method allows us to look back in time and make good estimates of the movement and impact of FADs from before tracking programs, as well as examine their potential impact on tuna behaviour.

"This collaboration between fishing companies, regional management organisations and researchers has resulted in an extraordinary amount of useful data that will go a long way towards helping Pacific island nations and the fisheries managers maintain the sustainability of this valuable $6 billion a year industry. It's a great example of managers, industry and researchers working together for the benefit of all."

1. Scutt Phillips, J., Escalle, L., Pilling, G., Sen Gupta, A., & van Sebille, E. (2019). Regional connectivity and spatial densities of drifting fish aggregating devices, simulated from fishing events in the Western and Central Pacific Ocean. Environmental Research Communications, 1(5), 055001. here

2. Escalle, L., Scutt Phillips, J., Brownjohn, M., Brouwer, S., Sen Gupta, A., Van Sebille, E., ... Pilling, G. (2019). Environmental versus operational drivers of drifting FAD beaching in the Western and Central Pacific Ocean. Scientific Reports, 9(1), 14005.

University of New South Wales

Related Coral Reefs Articles:

Can coral reefs 'have it all'?
A new study outlines how strategic placement of no-fishing marine reserves can help coral reef fish communities thrive.
Coral reefs 'weathering' the pressure of globalization
More information about the effects human activities have on Southeast Asian coral reefs has been revealed, with researchers looking at how large-scale global pressures, combined with the El Niño Southern Oscillation (ENSO) climate pattern, can detrimentally impact these delicate marine ecosystems.
Coral reefs: Centuries of human impact
In her AAAS talk, ASU researcher Katie Cramer outlines the evidence of the long-ago human footprints that set the stage for the recent coral reef die-offs we are witnessing today.
Large 'herbivores of the sea' help keep coral reefs healthy
Selective fishing can disrupt the delicate balance maintained between corals and algae in embattled Caribbean coral reefs.
How microbes reflect the health of coral reefs
Microorganisms play important roles in the health and protection of coral reefs, yet exploring these connections can be difficult due to the lack of unspoiled reef systems throughout the global ocean.
3-D printed coral could help endangered reefs
Threats to coral reefs are everywhere--rising water temperatures, ocean acidification, coral bleaching, fishing and other human activities.
Actions to save coral reefs could benefit all ecosystems
Scientists say bolder actions to protect the world's coral reefs will benefit all ecosystems, human livelihoods and improve food security.
Coral reefs shifting away from equator
Coral reefs are retreating from equatorial waters and establishing new reefs in more temperate regions, according to new research in the journal Marine Ecology Progress Series.
Protecting coral reefs in a deteriorating environment
A new report examines novel approaches for saving coral reefs imperiled by climate change, and how local decision-makers can assess the risks and benefits of intervention.
Coral reefs can't return from acid trip
When put to the test, corals and coralline algae are not able to acclimatise to ocean acidification.
More Coral Reefs News and Coral Reefs Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at