1. 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

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

3. 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: )

4. 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: )

5. Compatible and Conflicting Objectives

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

7. 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.

8. IATTC Trends in Catch by Species
2013: t

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

10. WCPO Purse Seine Fishery
Number of vessels
2013 : 297 vessels

11. IATTC Trends in Fleet Capacities
Longline
Millions
Purse Seine

12. 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, p.

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

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

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

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

17. 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%)

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

19. 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

20. North Pacific Blue Shark Stock Status 1971-2011

21. 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, (2006) 21

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

23. 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 Bull. Mar. Sci. 70(2):

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

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