Abundance Trends and Fisheries for Highly Migratory Species in the Pacific Ocean Jon Brodziak National Marine Fisheries Service Pacific Islands Fisheries Science Center Honolulu, Hawaii, USA

Overview Sustainability and Management Goals Regional Fisheries Management Organizations for Tuna Stocks Trends and Status of Tuna Stocks

Classifying the Scientific Study of the Sustainability of Fisheries Classical Sustainability (through 1970s): Population models without environmental variability Biological reference points Modern Sustainability (1980s-1990s): Population models with environmental variability Harvest control rules and the precautionary approach Post-Modern Sustainability (2000s): Extends sustainability concepts: Uses ecological & socioeconomic indicators Develops an ecosystem approach to management Quinn and Collie (2005. Phil. Trans R. Soc. B. 360: 147-162)

Types of Objectives for Fisheries Management Biological: Maximum Sustainable Yield (MSY) Fishery Yield Indicator Economic: Maximum Economic Yield (MEY) Industry Profit Indicator Societal: Maximum Job Yield (MJY) Employment Indicator Political: Minimum Sustainable Whine (MSW) Ecosystem Preservation Indicator “Whine” meaning “to complain to political powers” Hilborn (2007. Marine Policy. 31: 153-158)

Compatible and Conflicting Objectives

Western and Central Pacific Fisheries Commission and Inter-American Tropical Tuna Commission WCPFC RAY ≈ 2.5 mmt IATTC RAY ≈ 0.6 mmt

Western and Central Pacific Pelagic Fisheries: Trends in Catch by Species Source for this and next 9 slides: WCPFC 10th Regular Session of the Scientific Committee, Majuro, Republic of the Marshall Islands, 6-14 August 2014.

IATTC Trends in Catch by Species 2013: 585 000 t

Western and Central Pacific Pelagic Fisheries: Trends in Catch by Fishing Gear

WCPO Purse Seine Fishery Number of vessels 2013 : 297 vessels

IATTC Trends in Fleet Capacities Longline Millions Purse Seine

WCPO Skipjack Tuna High M Increasing Catch Not Overfished and Not Overfishing Increasing Fishing Mortality Source: The Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean. Scientific Committee. Regular session (7th : 2011 : Pohnpei, Federated States of Micronesia) Seventh regular session, Pohnpei, Federated States of Micronesia, 9–17 August 2011 : summary report. – Kolonia, Pohnpei : Western and Central Pacific Fisheries Commission, 2011. 203 p.

WCPO Yellowfin Tuna Intermediate M Increasing Catch Not Overfished and Not Overfishing Approaching an overfished condition Increasing Fishing Mortality

WCPO Bigeye Tuna Low M Increasing Catch Experiencing Overfishing and Overfished Increasing Juvenile Fishing Mortality

Spawning biomass ratio EPO Bigeye Tuna Spawning biomass ratio Base Case (h=1.0) Sensitivity Analysis (h=0.75)

Expansion of FAD fishery EPO Bigeye Tuna Catch by Gear Type Expansion of FAD fishery

Bigeye tuna dart tag recapture positions (> 30 DAL), color coded by area of release, based on Kurt Schaefer et al. (In press. Fisheries Research) Recoveries CPO (120° W to 180°) EPO (E of 120°W) WPO (W of 180°) CPO 5415 3311(61.1%) 1607 (29.7%) 497 (9.2%) EPO 6692 159 (2.4%) 6533 (97.6%) 0 (0.0%) WPO 456  20 (4.4%) 0 (0.0%) 436 (95.6%)

Pacific Bluefin Tuna Catch by Country Total catch 2013 was 12,124 mt, decreased from 15,636 mt in 2012 Average F during 2009-2011 exceeds all commonly used BRPs SSB in 2012 was 26,324 mt, less than 6% of unfished SSB

Impact on SSB by Fishery Pacific Bluefin Tuna For illustrative purposes, two examples of Kobe plots (plot A based on SSBMED and FMED, plot B based on SSB20% and SPR20%) are presented. Impact on SSB by Fishery

North Pacific Blue Shark Stock Status 1971-2011

Long-term Increase in Tuna Catches in the Pacific Ocean, 1950-2004 “Probably all the great sea fisheries are inexhaustible” ~ Thomas Huxley 1884 “It is a mistake to suppose that the whole ocean is practically one vast store house” ~ Ray Lankester 1884 Source: Sibert et al., Science 314, 1773 -1776 (2006) 21

How Can We Build Sustainable HMS Fisheries ? Quantify Conservation Goals Identify Robust Management Procedures Ensure Adequate Monitoring

Ecological Decision Making with Diverse Human Value Systems in Tuna RFMOs Accountability: Explicit About Decision Criteria Legitimacy: Explicit About Policy Strategies Flexibility: Explicit About Uncertainties Brodziak and Link. 2002. Bull. Mar. Sci. 70(2):589-611

Will Future Pacific Tuna Fisheries Be Sustainable ? International Cooperation Ethic of Restraint

Thank You ~ Mahalo With special thanks to Shelton Harley, Nick Davies, Joel Rice, Kurt Schaefer, & all my SPC, ISC, IATTC & WCPFC colleagues