“THE END OF THE LINE” :
HOW SOUND IS THE SCIENCE?
Doug S Butterworth
MARAM (Marine Resource Assessment and Management Group)
Department of Mathematics and Applied Mathematics
University of Cape Town, Rondebosch 7701, South Africa
OUTLINE
I.
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
SY
MSY
PRISTINE
BMSY
0
B
0
30-40%
100%
Fisheries management target BMSY
TERMINOLOGY
BMSY
FISHERIES:
0
20
OVER EXPLOITED
50
FULLY EXPLOITED
100
B
UNDER EXPLOITED
IUCN RED LIST:
0
20
CRITICALLY
ENDANGERED
50
ENDANGERED
70
B
VULNERABLE
CONTRADICTION?
NO
IUCN fishing intended as flag waver based on crude analysis NOT definitive
assessment of status
II. BLUEFIN TUNA

North Pacific Bluefin Tuna

Southern Bluefin Tuna

North Atlantic Bluefin Tuna
Two 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 farms
Effort (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 reduction
Believable?
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 FOUNDATION
STATUS OF WORLD TUNA RESOURCES
TRENDS RELATIVE TO BMSY
Jeff Hutchings et al.: Can. J. Fish. Aquat. Sci. 67 (2010) 1205-1210
WORLDWIDE:
Pelagic
HIGH SEAS
Demersal
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) 578-585
Average 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
Moderately exploited
Fully exploited
Overexploited
Recovering from depletion
Depleted
2%
18%
52%
19%
1%
8%
72%
28%
CURRENT WORLD SITUATION
Worm, Hilborn et al. (2009) database (255 stocks)
Underexploited
Fully exploited
24%
50%
74%
Overexploited
Collapsed
14%
12%
26%
CURRENT SOUTH AFRICAN
SITUATION
Worm, Hilborn et al. (2009) database:
255 stocks – 8 from South Africa
Underexploited
Fully exploited
Overexploited or Collapsed
2
6
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 AREAS
Practical-enforcement approach to indirectly keep catches
sustainable

OFFSHORE AREAS
Generally little to offer mobile species from a sustainability
standpoint
Confound interpretation of data used for assessment
Spatio-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 it
Seeming reluctance of Nature to publish rebuttals
THE 90% PAPER
Tom 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 PAPER
Seattle 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 Pay
Laudable objective to promote sustainability
BUT Questionable Publicity
Investec: “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?
OR
A 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 sufficient
Mike 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 oversold
Require 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 attention
Acknowledgements for assistance with presentation
information/development and preparation:
Trevor Branch
Ray Hilborn
Laurie Kell
Mark Maunder
Andrea Müller
Victor Restrepo
William Robinson
(Univ. Washington)
(Univ. Washington)
(ICCAT)
(IATTC)
(ISSF)