The Western and Central Pacific tuna fishery: 2016 overview and status of stocks / by Francisco Blaha

As usual, SPC publishes excellent material. Their latest overview and status of stocks is no exemption. Authored by Stephen Brouwer, Graham Pilling, John Hampton, Peter Williams, Sam McKechnie and Laura Tremblay-Boyer is compulsory reading is you have an interest in the WCP tuna fishery, hence download from here.

nah bro... this ones don't count

nah bro... this ones don't count

I just quote the introduction for easy reference (but nothing ever beats the original!)

The tuna fisheries in the western and central Pacific Ocean (WCPO), encompassed by the Convention Area of the Western and Central Pacific Fisheries Commission (WCP-CA), are diverse, ranging from small-scale, artisanal operations in the coastal waters of Pacific states, to large-scale, industrial purse-seine, pole-and-line and longline operations in the exclusive economic zones (EEZs) of Pacific states and in international waters (high seas). The main species targeted by these fisheries are skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (T. obesus) and albacore tuna (T. alalunga).

The current fishery characterisation includes updates to historical data, which show that the highest catch year was 2014. We expect revisions to the 2016 catch estimates in next year's report, as catch estimates in the most recent year are preliminary.

Annual total catch of the four main tuna species (skipjack, yellowfin, bigeye and albacore) in the WCP-CA increased steadily during the 1980s as the purse-seine fleet expanded, and remained relatively stable during most of the 1990s until the sharp increase in catch in 1998. Since then there has been an upward trend in total tuna catch, primarily due to increases in purse-seine catch with some stabilisation since 2009.

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The provisional total WCP-CA tuna catch for 2016 was estimated at 2,686,203 tonnes (t) - a small drop from the record high of, 2,883,196t experienced in 2014. In 2016 the purse-seine fishery accounted for an estimated 1,832,761t (68% of the total catch), a drop from the record high of, 2,059,007t experienced in 2014 for this fishery. The pole-and-line fishery landed an estimated 199,081t (7% of the catch - a drop from the highest value (415,016t), recorded in 1984).

The longline fishery in 2016 accounted for an estimated 235,500t (9% of the catch) - a decrease from the highest value (284,782t) recorded in 2004. Troll gear accounted for 5% of the total catch (141,046t), a record catch, this was mainly due to a separation of the Indonesian troll catch from their combined artisanal gear catch.

The remaining 10% was taken by a variety of artisanal gear, mostly in eastern Indonesia, the Philippines and Vietnam, which is a drop from the highest value (311,123t), recorded in 2015.

The WCP-CA tuna catch for 2016 represented 79% of the total Pacific Ocean catch (3,384,604t) and 55% of the global tuna catch (the provisional estimate for 2016 is 4,860,736t).

The 2016 WCP-CA catch of skipjack (1,786,463t - 67% of the total catch) was a drop from the highest value (2,002,512t), recorded in 2014; a decrease of 1% from 2015. The WCP-CA yellowfin catch for 2016 (649,446t - 24%) is a record catch. The WCP-CA bigeye catch for 2016 (150,884t - 6%) was a drop from the highest value (192,564t), recorded in 2004, and a 10% increase over the 2015 catch. The 2016 WCP-CA albacore catch (65,959 - 2%) was a drop from the highest value (84,949t), recorded in 2010.

The 2016 purse-seine catch of 1,832,761t was lower than the previous year.

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The 2016 purse-seine skipjack catch (1,372,923t - 77% of the total skipjack catch) was 2% lower than the 2015 catch. The 2016 purse-seine catch of yellowfin tuna (394,262t) was a 30% increase from 2015. The purse-seine catch estimate for bigeye tuna for 2016 (62,066t) was 14% lower than in 2015, and represented 41% of the total 2016 bigeye catch. Catches of all three species have declined due to a 10% decline in purse seine effort in 2015. However, it is important to note that the purse-seine species composition for 2016 will be revised once all observer data for 2016 have been received and processed, and the current estimate should, therefore, be considered preliminary.

The 2016 longline catch of 235,500t represents a decrease from the highest value (284,782t) recorded in 2004. The recent longline catch estimates are often uncertain and subject to revision due to delays in reporting. Nevertheless, the bigeye (63,197t) catch was low relative to the previous 15 years, while the yellowfin (89,028t) catch for 2016 was the highest since 2004.

The 2016 pole-and-line catch of 199,081t was low, and represented an 8% decrease from the 2015 catch. Skipjack accounts for the majority of the catch (85%). Yellowfin tuna (13%) make up the bulk of the remaining pole-and-line catch. The Japanese distant-water and offshore fleet and the Indonesian fleet account for most of the WCP-CA pole-and-line catch.

The 2016 troll catch in the WCPO of 141,046t was 34% higher than the 2015 catch - most of the catch being skipjack tuna. South Pacific albacore are also taken by troll gear. Since 2007 New Zealand (averaging about 2,338t catch per year) has had the most consistent effort in the south Pacific albacore troll fishery, with the United States landing a small catch (average 266t per year) in the south Pacific.

Inquiries regarding this report or other aspects of the work program of the OFP should be directed to:

Chief Scientist and Deputy Director FAME (Oceanic Fisheries)
Pacific Community
98848 Noumea Cedex
New Caledonia