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.