Western and Central Pacific High Seas (ABNJ) Closures for the Purse Seine Skipjack Tuna Fishery

December 2012

INTRODUCTION AND BACKGROUND

In 2008, the Western and Central Pacific Fisheries Commission (WCPFC), the regional fisheries management organization for tuna in the western and central Pacific Ocean (WCPO), adopted a binding measure that closed fishing by purse seine tuna vessels in two of four pockets in areas beyond national jurisdiction (ABNJ), which are areas of the high seas that are wholly enclosed by Exclusive Economic Zones (EEZs) of Pacific Island States (Figure 1). The measure went into effect on 1 January 2010. WCPFC eliminated the two "doughnut hole" closures at its March 2012 meeting, replacing it with a measure that temporarily instituted input and output limits, observer coverage requirements, prohibited Philippines purse seine fishing in high seas pocket number 2 (Figure 1), and other measures (WCPFC, 2012). The March 2012 measure was extended at the most recently convened WCPFC December 2012 meeting, and is now in effect through the end of 2013.

Some of the purse seine foreign license access agreements issued by the Pacific Islands Forum Fisheries Agency (FFA) restrict fishing grounds to within the Pacific Island EEZs and prohibit fishing on the high seas in the tropical WCPO, including in the two high seas pockets that had previously been closed to purse seine fishing by WCPFC. Under bilateral agreements, however, the Philippines and USA (under the US Multilateral Treaty) are two purse seine distant water fishing nations permitted to fish in high seas areas without compromising the terms of their access to fishing in Pacific island State EEZs.

An initial ecological rationale for closing the tropical WCPO high seas to purse seine fishing was to reduce pressure on overexploited tuna resources, in particular, to contribute to meeting stock management objectives for the WCPO bigeye tuna stock, for which overfishing is currently occurring[1], and prevent healthy tuna stocks from becoming overexploited, in part, by allowing for more effective control over illegal fishing. However, as explained in the next section, studies found that the WCPFC high seas pocket closures did not cause a reduction in purse seine fishing effort or bigeye tuna fishing mortality due to the redistribution of effort. Prohibiting purse seine high seas fishing in the WCPO, however, does provide substantial socioeconomic benefits to developing Pacific Island States from the exploitation of tropical tuna resources as it forces distant water fishing nations to fish in domestic waters of Pacific island States - therefore, high seas closures affect the allocation of tuna resources.

Delegations to WCPFC from some of the purse seine distant water fishing nations (including the USA, Japan, Taiwan, Korea, EU) called for the elimination of the two high seas pocket purse seine closures previously established by WCPFC, and have not supported the closure of the two additional WCPO high seas pockets. Instead, the distant water fishing nations have called for managing the high seas pockets as Special Management Areas, subject to an entry-exit notification scheme, in an effort to control illegal fishing (i.e., basically reverting to the management system employed prior to instituting area closures, but with improved deterrents of illegal fishing). The Parties to the Nauru Agreement (PNA) has asserted that they will continue to prohibit purse seine fishing in the two high seas pocket closures through FFA license agreements, and has proposed the closure to purse seine vessels of two additional high seas pockets (Figure 1, Areas 3 and 4), and the closure of all high seas to longline tropical tuna fisheries that are issued FFA foreign license access agreements.

Figure 1. Location of two high seas pockets (areas 1 and 2) previously closed to purse seine fishing by WCPFC and currently closed via some FFA foreign license agreements. Areas 3 and 4 are two additional high seas pockets which FFA has proposed to also close to purse seine fishing (Figure from WCPFC, 2012).

THE ECOLOGICAL OBJECTIVES AND PERFORMANCE OF THE CLOSURES

The high seas closures did not likely contribute to meeting objectives for reducing bigeye tuna fishing mortality, based on observations that the closures were not effective in constraining growth in purse seine effort (SPC-OFP, 2010). Fitting past fishing effort data to a model found that the closure of the high seas WCPO pockets and proposed additional high seas areas would have resulted in only a small increase in stock-wide bigeye biomass, with slightly larger localized population increases near the closed areas (Sibert et al., 2012). Analyses have not been conducted to assess the effect of the high seas pocket closures on other stocks of species groups that are vulnerable to fisheries overexploitation, and it is unclear how the redistribution of fishing effort from the high seas to domestic waters affected the age class distribution of fishing mortality (i.e., was there a significant effect on the fishing mortality by age class of bigeye tuna and other species as a result of the change in fishing grounds) (Gilman, 2011; Sibert et al., 2012).

The high seas pocket closures did not reduce total fishing effort, which was displaced from the high seas into PNA waters. When the WCPFC closures were in effect, total purse seine effort increased by 10% in the EEZs surrounding the two pocket closures – i.e., purse seine effort was displaced to areas adjacent to the closures and overall effort increased (SPC-OFP, 2010). The high seas pocket closures could contribute to meeting bigeye tuna stock management objectives if historical purse seine effort that had been conducted in these areas is not displaced to other areas where bigeye catch rates are similar or higher. But even with this scenario, the closures would be insufficient as a stand-alone measure to meet recommended reductions in bigeye tuna fishing mortality.

The WCPO high seas pocket closures per se had a nominal contribution to meeting WCPO bigeye tuna stock management objectives. The closures were adopted largely over issues involving the allocation of tuna resources.

In conclusion, time/area restrictions can contribute to meeting stock management objectives for fisheries for highly migratory species, but need to be combined with other management tools to maintain fishing mortality within biological limit reference points. Consideration of the complex allocation consequences between distant water and coastal States, and between gear types, of maintaining, expanding, or eliminating the high seas closed areas and other control measures on fishing for WCPO tropical tuna (Hanich and Ota, In Press) is warranted in considering alternative management measures to meet ecological objectives.

REFERENCES

Cook Islands (2010) Conservation and Management Measure for the Eastern High- Seas Pocket Special Management Area. WCPFC7-2010-DP/04 (Western and Central Pacific Fisheries Commission, Seventh Regular Session, Honolulu, HI).

Davies, N., et al. (2011) Stock Assessment of Bigeye Tuna in the Western and Central Pacific Ocean. WCPFC-SC7-2011/SA-WP-02. Western and Central Pacific Fisheries Commission, Pohnpei, Federated States of Micronesia.

Gilman, E. (2011) Bycatch governance and best practice mitigation technology in global tuna fisheries. Marine Policy 35: 590-609.

Gilman, E., Passfield, K., Nakamura, K. 2012. Performance Assessment of Bycatch and Discards Governance by Regional Fisheries Management Organizations. ISBN: 978-2-8317-1361-8. International Union for the Conservation of Nature, Commission on Ecosystem Management and Oceania Regional Office, Gland, Switzerland and Suva, Fiji.

Hanich, Q., Ota, Y. (In Press) Moving beyond rights based management: A transparent approach to distributing the conservation burden in tuna fisheries. International Journal of Marine and Coastal Law.

PNA Group (2010) PNA Proposed CCM to Close Purse Seine Fishing in Additional High Seas Areas. WCPFC7-2010-DP/06. Western and Central Pacific Fisheries Commission, Pohnpei, Federated States of Micronesia.

Secretariat of the Pacific Community–Oceanic Fisheries Programme (SPC-OFP) (2010) Review of the Implementation and Effectiveness of CMM 2008-01. WCPFC7-2010/15. Western and Central Pacific Fisheries Commission, Pohnpei, Federated States of Micronesia.

Sibert, J., Senina, I., Lehodey, P., Hampton, J. (2012) Shifting from marine reserves to maritime zoning for conservation of Pacific bigeye tuna (Thunnus obesus). PNAS: doi:10.1073/pnas.1209468109.

WCPFC (2008) Conservation and Management Measure for Bigeye and Yellowfin Tuna in the Western and Central Pacific Ocean. CMM 2008-01. Western and Central Pacific Fisheries Commission, Palikir, Federated States of Micronesia.

WCPFC (2012) Conservation and Management Measure for Temporary Extension of CMM 2008-01. CMM 2011-01. Western and Central Pacific Fisheries Commission, Palikir, Federated States of Micronesia.

[1] The 2011 stock assessment for WCPO bigeye tuna estimates the current biomass to be slightly above the biomass capable of producing maximum sustainable yield (MSY), but the estimated fishing mortality rates are greater than the fishing mortality at MSY (Davies et al., 2011). I.e., if allowed to continue, current exploitation rates will reduce the bigeye tuna stock to less than that capable of producing MSY.