Richard Musgrove
The threat of climate change has spurred the UN’s Green Climate Fund to provide a grant for 14 Pacific Island nations to purchase fish aggregation devices and other tools to manage food security risks associated with future tuna catches.
The grant programme is worth almost $250m (US$156.8m).
A third of the world’s tuna catch comes from waters around 14 nations in the Western and Central Pacific including The Cook Islands, Fiji, the Federated States of Micronesia, Kiribati, the Marshall Islands, Nauru, Niue, Palau, Papua New Guinea, Samoa, the Solomon Islands, Tonga, Tuvalu, and Vanuatu.
Species caught are mostly Skipjack and Yellowfin, with the remainder Albacore and Bigeye.
But, as the ocean continues to heat up, tuna populations are predicted to move east or south, away from the islands whose economies they support. Tuna catches are expected to decline 30% by 2050, equivalent to losses of $40-140 million annually, 8-17% of government revenue per year for individual tuna-dependent economies.
A generalised decline in tuna populations is also expected over the same timeframe, as climate-change induced ocean current and water chemistry variations become more extreme.
The programme is aimed at providing tools to develop and support climate adaptation. Understanding when and to what extent ocean warming will change the distribution of fish stocks is a key part of solution identification, says Johan Bell, Senior Director for Tuna Fisheries at Conservation International (CI).
FAD and tuna
Tools such as Fish Aggregating Devices (FADs) — systems of floats, nets and lights anchored on the surface or below, to attract pelagic fish. The funds will foster FAD use.
The Marine Stewardship Council, (MSC) a non-profit which aims to “end overfishing” says FAD’s cast a shadow into the water to attract groupings of fish.
“By casting their nets and fishing rods near these floating objects, fishers can increase their catches with less effort. This can, however, result in a higher level of bycatch,” MSC says on its website.
“FADs can be classified as entangling and non-entangling. Traditionally FADs were produced using nets or meshed materials. These nets could accidentally trap species such as sharks and turtles. Non-entangling FADs use ropes or nets rolled up to avoid entangling marine fauna.”
MSC also says a wide variety of marine life including turtles and sharks congregate around FADs and can become entangled in the floating nets attached to FADs.
“Such “non-target” species can also be caught as bycatch (accidental catch) in the nets or lines fishers cast from their boats. As a result, bycatch can be high when fishing around FADs, particularly in comparison to free school fishing, where nets are set in open water.
“High amounts of bycatch can have detrimental impacts on the ecosystem. FADs can also increase the capture of juveniles, putting the sustainability of some tuna stocks at risk.
“However, species interact differently with different types of FADs, and different fishing techniques can make dramatic differences in the level of bycatch.”
Ian Bertram, the Pacific Community Principal Fisheries Adviser, says FADS improve catches and safety at sea…”…and reduce fuel use because boats do not have to keep following fast-moving tuna.”
Jack Kittinger, Senior Vice President, Center for Sustainable Lands and Waters at CI says: “This investment will secure the region’s position as a leader in tuna fisheries management while highlighting the urgency of global climate action.”
The lives of Pacific tuna
