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Transcript of Doug S Butterworth MARAM (Marine Resource Assessment and Management Group) Department of Mathematics...
Doug S Butterworth
MARAM (Marine Resource Assessment and Management Group)Department of Mathematics and Applied Mathematics
University of Cape Town, Rondebosch 7701, South Africa
“THE END OF THE
LINE” :HOW SOUND IS THE SCIENCE?
OUTLINEI. Terminology
II. Bluefin Tuna
III. 90% of Large Predatory Fish Gone?
IV. Collapse of Fisheries by 2048?
V. Current World and South African Situation
VI. The “MPA Solution”
VII. Science, Advocacy and Ethics
VIII. In Summary
I. TERMINOLOGY SUSTAINABLE YIELD vs ABUNDANCE
0 30-40% 100%Fisheries management target
BMSY
B
SY
BMSY
PRISTINE
0
MSY
TERMINOLOGY FISHERIES:
0 20
50
100
OVER EXPLOITED
FULLY EXPLOITED
UNDER EXPLOITED
BMS
Y B
CONTRADICTION?
IUCN RED LIST:
IUCN fishing intended as flag waver based on crude analysis NOT definitive assessment of status
NO
0 20
50
70
CRITICALLY ENDANGERED
ENDANGERED VULNERABLE
B
II. BLUEFIN TUNA
North Pacific Bluefin Tuna
Southern Bluefin Tuna
North Atlantic Bluefin TunaTwo populations: West ; East +
Mediterranean
NORTH ATLANTIC BLUEFIN TUNA
Regional Fisheries Management Organisation:
ICCAT
International Commission for the Conservation of Atlantic Tunas
International Commission for Catching All the Tunas
NORTH ATLANTIC BLUEFIN CATCH DISTRIBUTION
ICCAT AND EASTERN BLUEFIN
MID 1990’s to MID 2000’s
Development of farming
Complete loss of control in the Mediterranean
Increasing uncertainty about size of catch
Continued cynical attitude to science from EU
EAST ATLANTIC & MEDITERRANEAN
BLUEFIN CATCHES
EAST ATLANTIC BLUEFIN RECENT DEVELOPMENTS
2009 ICCAT Meeting:TAC reduced to 13 500 tons
100% observer coverage of farmsEffort (season length) restrictions
2010 CITES:Proposal to list Atlantic bluefin
Fails: “Leave it to ICCAT”
CAN ICCAT DELIVER?
2010 ICCAT ASSESSMENT EAST ATLANTIC BLUEFIN CATCH RATES (CPUE)
2010 ICCAT ASSESSMENT EAST ATLANTIC BLUEFIN SPAWNER BIOMASS
2010 ICCAT ASSESSMENT EAST ATLANTIC & MEDITERRANEAN BLUEFIN
CATCH
2010 ICCAT ASSESSMENT
Marked recent catch reductionBelievable?
A new EU?
Increased biomass estimates and improved trends
Maintenance of 13 500 ton TAC should see rebuilding to BMSY by 2022 (MSY = 50 000 tons)
Green listing?
III. 90% OF LARGE PREDATORY FISH GONE?
Myers and Worm: Nature 423 (2003) 280-283
Global ocean has lost more than 90% of large predatory fishes
Primarily based on Japanese tuna longline data
Five substantial rebuttal papers Hampton, Maunder, Polacheck, Sibert,
Walters
90% OF LARGE FISH GONE? PACIFIC YELLOWFIN & BIGEYE TUNA CPUE &
CATCHES
90% OF LARGE FISH GONE?
Analysis no longer has any credence in the fisheries science community
The End of the Line (Jeff Hutchings, Daniel Pauly):
“Whether it’s 95% or 70% is rather irrelevant; these are still dramatic declines”
BUT: 70% decline is close to BMSY target ??!!
ISSF – TUNA STATUS INTERNATIONAL SEAFOOD SUSTAINABILITY
FOUNDATIONSTATUS OF WORLD TUNA RESOURCES
Jeff Hutchings et al.: Can. J. Fish. Aquat. Sci. 67 (2010) 1205-1210
WORLDWIDE: Pelagic Demersal
HIGH SEAS
TRENDS RELATIVE TO BMSY
IV. COLLAPSE OF FISHERIES BY 2048?
Worm et al.: Science 314 (2006) 787-790
Project all fisheries collapsed by 2048“Collapse” – catch below 10% of
maximum
Based on catch, not abundance data
Eleven substantial rebuttal papers Branch, Briggs, de Mutsert, Hilborn
(x3), Holker, Jaenike, Longhurst, Murawski, Wilberg
TREVOR BRANCH: TRENDS IN “COLLAPSED”
FISHERIES
2048 PREDICTION
COLLAPSE OF FISHERIES BY 2048?
WWF (Argus, 22 October 2010) re “The End of the Line”:
“Never before have our marine resources been as degraded and overfished as they are today”
Worm, Hilborn et al.: Science 325 (2009) 578-585Average exploitation rate recently declined in 5 of 10 ecosystems
For 7 of these systems, rate is lower than required to achieve BMSY
Iceland, US Northeast, Newfoundland, S Australia, East Bering Sea, California, New Zealand
The 2048 prediction has long been without any credence in the fisheries science community
V. CURRENT WORLD AND SOUTH AFRICAN
SITUATION FAO 2010 CLASSIFICATION OF FISH
STOCKS
Underexploited 2%Moderately exploited 18%
72%Fully exploited 52%Overexploited 19%Recovering from depletion 1%
28%Depleted 8%
CURRENT WORLD SITUATION
Worm, Hilborn et al. (2009) database (255 stocks)
Underexploited 24%Fully exploited 50%
Overexploited 14%Collapsed 12%
74%
26%
CURRENT SOUTH AFRICAN SITUATION
Worm, Hilborn et al. (2009) database: 255 stocks – 8 from South Africa
Underexploited 2Fully exploited 6Overexploited or Collapsed 0
Under: shallow-water hake, toothfish
Fully: anchovy, horse mackerel, deepwater hake, kingklip, sardine, south coast rock lobster
Not considered: abalone, sole, squid, west coast rock lobster, line fish
VI. THE “MPA SOLUTION”
The End of the Line:Abundance increases in Marine Protected
Areas
BUT Does this lead to greater productivity
and hence catches?Yes, insofar as near-sessile species “spill over” outside the MPA
Will MPAs prevent over-exploitation of mobile species?Hardly – fish become catchable once they move outside
THE “MPA SOLUTION”
INSHORE AREASPractical-enforcement approach to indirectly keep catches sustainable
OFFSHORE AREASGenerally little to offer mobile species from a sustainability standpoint Confound interpretation of data used for assessmentSpatio-temporal closures more effective for effort control if needed
VII. SCIENCE, ADVOCACY AND ETHICS
Special additional reasons for fisheries scientists’ concerns (raised hackles) about the 90% decline (Nature) and 2048 projection (Science) papers
Re 90% paper:“Widely rumoured” that a senior reviewer had rejected itSeeming reluctance of Nature to publish rebuttals
THE 90% PAPERTom Polacheck (Marine Policy 30 (2006) 470-482): Failure to address concerns of tuna scientists Claiming falsely that cited papers demonstrated a
consistency between apparently inconsistent data sets when they didn’t
Claiming discovery of already well known phenomena Implying those working in the field had tunnel
vision/emotional attachment to their work to undercut their potential criticism
Making emotive undocumented universal claims in publicity statements
Mark Maunder et al. letter to Nature :Publishing and promoting highly questionable science
without allowing timely critical review by qualified people ... does science a disservice
Nature : Acknowledged wide-spread criticism by experts in the field, but declined to publish the letter
Polacheck : Nature appeared to divorce itself from responsibility for accuracy and general validity of conclusions of an article once published
THE 2048 PAPERSeattle Times report
(http://seattletimes.nwsource.com/html/localnews/2003340489_seafood03m.html)
The author sent a note to colleagues (and the Seattle Times by mistake) saying “... that the projection could act as a ‘news hook’ to get people’s attention ...”
Mike Beck (in The Nature Conservancy’s Science Chronicles Jan 2007)
“F “ in high school statistics
Represents targeted advocacy by some journals and authors. Polarisation, rather than needed co-operation with fishing interests, fuelled by one-sided papers in Science and Nature
Mike Sissenwine (in Environmental Conservation 34 (2007) 90-91)
Aggressive public promotion of science is fine and legitimate provided rigour and accuracy are not sacrificed.
The people whom fisheries scientists seek to influence deserve to know whether they are reading or hearing objective science or advocacy.
Proposed that fisheries scientists be governed by codes of conduct, standard practices, certification and licensing, well beyond journal peer review, similar to internal governance within other professions interacting with lay-people such as doctors, engineers and lawyers.
VIII. IN SUMMARY
The End of the Line:Sound science?
In part, but certainly not throughout
Up to date?No
Balanced?Certainly not
But interpret it for what it intends to be –
advocacy
IN SUMMARY The End of the Line
Local sponsors: WWF, Investec, Pick n PayLaudable objective to promote sustainability
BUT Questionable PublicityInvestec: “A world without fish .... around 2048”
“90% of all large fish fished out” (citing WWF)
Promoting false information is counter-productive towards influencing the fishing industry
Why aren’t these companies who want to do “the right thing” better informed?Lack of due diligence on their part?
ORA failure of mainstream science to communicate effectively?
IN SUMMARY
The End of the Line – Three Steps
Ask before you buy – eat only sustainable seafood
Join the campaign for MPAs and responsible fishing
Tell politicians – respect the science and cut the fishing effort
IN SUMMARY
The End of the Line – Step One
Ask before you buy – eat only sustainable seafood
YES BUT
Be aware of the source of the advice as to sustainability
e.g. Special interest groups - some systems mark ANY trawl caught fish red
Hilborn: Trawling provides 7% of meat and fish consumption worldwide
Replace that fish by meat production through grazing: requires area five times the size of remaining rain forest
Which is more environmentally friendly: fishing or meat production?
IN SUMMARY
The End of the Line – Step Two
Join the campaign for MPAs and responsible fishing
MPAs are neither a panacea nor sufficientMike Beck (in The Nature Conservancy’s Science Chronicles Jan 2007)
The few solutions that are offered are simplistic, e.g. ‘lets stop fishing in certain areas’
The concept is being heavily oversoldRequire cogent scientific rationale before implementing any specific proposal
IN SUMMARY
The End of the Line – Step Three
Tell politicians – respect the science and cut the fishing effort
YES! YES! YES!
THIS IS WHAT REALLY MATTERS!
90% of the world’s fisheries problems will be rapidly solved by ensuring respect for sound scientific advice on catches, and reducing available fishing effort to the corresponding level needed
Thank you for your attentionAcknowledgements for assistance with presentation information/development and preparation:
Trevor Branch (Univ. Washington)Ray Hilborn (Univ.
Washington)Laurie Kell (ICCAT)Mark Maunder (IATTC)Andrea MüllerVictor Restrepo (ISSF)William Robinson