Pacific island fisheries face climate challenge
[PALAU] Some Pacific island nations should benefit from better fisheries following climate change, but there will be more losers than winners, according to a book published by the Secretariat of the Pacific Community (SPC) last month (7 November).
Johann Bell, an SPC fisheries expert and one of the editors of Vulnerability of Tropical Fisheries and Aquaculture to Climate Change, said that smaller nations in the central and eastern Pacific region that rely heavily on licence fees from tuna fishing fleets for government revenue — such as Kiribati, Nauru and Tuvalu — are expected to be among the winners.
This is because of a projected eastwards redistribution of skipjack and bigeye tuna due to changes in ocean temperatures, currents and nutrients.
According to Bell, the most likely losers in the tuna movement will be in the western part of the Pacific region, which includes Fiji, Solomon Islands and Papua New Guinea.
He added that higher rainfall in Papua New Guinea should boost its freshwater fisheries. But he warns that the changing patterns of rainfall and more intense storms are likely to increase the risk of floods.
The biggest losers are likely to be "the nations that will continue to rely heavily on coastal fisheries derived mainly from coral reefs", said Bell. In these countries, coral reefs are expected to suffer severely from more frequent bleaching due to warmer sea surface temperatures and acidification of the ocean.
The book estimates that coral reefs will decrease by 90 per cent and reef-associated fish by 50 per cent by the end of the century. It warns that the overall effect will be insufficient fish to feed the increasing populations of the Pacific islands.
Additional data comes from a recent report for the Australian government's Pacific Climate Change Science Program (PCCSP), the second volume of which contains reports from 15 Pacific island countries. It finds that the Pacific is getting hotter, sea levels are rising, rainfall is changing and equatorial winds have weakened.
The authors of 'Climate change in the Pacific: Scientific assessment and new research', released last month (25 November), added that further warming seems inevitable, given increases in greenhouse gases from human activities.
Scott Power, co-editor of the report, said that "the region will warm by between half and one degree Celsius over the next two decades, regardless of what emissions cuts are made before then. It's projected to warm by up to three degrees in the next eight decades, depending on greenhouse gas emissions in the future."
Bell pointed out that the way in which Pacific countries adapt to this warming will determine their future livelihoods.
Ways of coping include 'fish aggregating devices' to attract tuna closer to shore, changing fish management regimes, encouraging communities to grow fish in freshwater ponds, and improving management of mining and forestry industries to prevent sediments and nutrients spoiling fish habitats.