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Sustaining global capture fisheries production Ray Hilborn School of Aquatic and Fishery Sciences
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Overview of the talk Status of fish stocks Understanding sustainability Impacts of bottom trawling Forage fish impacts CFOOD e-media
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The end of the line
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All fish gone by 2048 Science 2006 2,445 Citations
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Source: Time magazine, November 2006
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NCEAS working group: Finding common ground in marine conservation and management
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The RAM Legacy Stock Assessment Database www.ramlegacy.org
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Coverage in RAM Legacy 40% of world catch
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Regional trends in biomass Source: Global Assessment Database (ramlegacy.org)
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Regional trends in exploitation rate Source: Global Assessment Database (ramlegacy.org)
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Yield lost by overfishing (red) and underfishing (yellow)
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Science 2012
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Assessed stocks stabilize, others decline Source: Costello et al. (2012) Science 338: 517-520 ~35% ~65% +
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Large stocks in good shape Average Catch in MT 1,000,000 100,000 10,000 1,000 100 10 1 U.S. definition of overfished
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Defining sustainability
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“Sustainability Science” William Clark editor of Sustainability Science for PNAS Our approach is grounded in a definition of sustainable development that focuses on the well being of people over the long run. In particular, it argues that the development of a social-environmental system is sustained over a period of time if over that period appropriately inclusive measures of well-being do not decline
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The three pillars of sustainable development IUCN Adams 2006
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Elements of sustainability Continued ability of the ecosystem to produce what we want Acceptable levels of environmental impact – Whose choice – Compared to what Social well being – Maintenance of fishing communities – Equity in income, gender – Human rights Economic performance
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Ah ha: sustainability is a state, abundant is sustainable, overfished is not
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Less by-catch but higher carbon footprint More by-catch but lower carbon footprint
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Sustainability is a process The worst way to measure sustainability is B/BMSY Better is F/FMSY The best is to evaluate the management system – Monitor abundance changes – Adjust exploitation rate in relation to abundance – Effectively enforce regulations
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A survey of fisheries governance Mike Melnychuk and Ray Hilborn 46 questions for 400 stocks Four areas: research, management, enforcement, socioeconomics … as examples ------------------------------------------------------------- Stock size and/or fishing mortality rate are reliably estimated Fishery management plan exists and strategies or tactics designed to meet objectives are specified Dockside monitoring and enforcement measures are sufficient for the fishery management system to effectively regulate fishing pressure
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Fisheries governance
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Evaluation of best practices for impacts of bottom trawling on benthic marine ecosystems A progress report
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An independent assessment of the science of benthic impacts A scientific team of international experts to – Determine the footprint of bottom trawling in different areas How much area? What kind of habitat? What trend in trawl footprint? – Determine the impact of trawling on different benthic organisms By gear type, habitat type, type of organism – Determine the indirect impact of bottom trawling on target species – Evaluate a range of possible best practices Impact on catch Impact on benthic organisms
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The Study Group
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Collecting the data -Vessel Monitoring System -Logbook data -Effort timeseries
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Trends in effort
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High resolution mapping of trawling global footprint
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Frequency of trawl coverage
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Global footprint of trawling
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Forage fish impacts on predators primarily marine birds and mammals Global policy conversation dominated by LENFEST report Many weaknesses in this report A 2 year project to review what is known about impacts Design management strategies
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Impacts of MPAs on fisheries yields Working group organized in conjunction with FAO We have had one meeting -- looking for a major supporter to continue the activity
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CFOOD e-media www.cfooduw.org Web site to provide independent science Track false claims in media Twitter and Facebook feeds
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The competing narratives Fishing continues to expand and empty the ocean … large areas of the ocean must be closed and many kinds of fishing banned Fishing provides a sustainable high quality food, and if properly managed protects the oceans and supports people
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Conclusions Where fisheries are being actively managed sustainability and rebuilding are the outcome Many important fishing countries do not actively manage their fisheries All fishing has impacts but good science suggests fishing impacts are low compared to alternative foods, and can be further reduced
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Thanks to NCEAS working group team – Especially Dan Ricard, Julia Baum, Coilin Minto, Olaf Jensen Trevor Branch and Boris Worm UCSB Dan Ovando and Chris Costello
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These stocks constitute 90% of global catch reported to FAO
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Pauly’s “status of fisheries” from catch data From Pauly 2007
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FAO has a very different trend
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Environmental impacts Measured in LCAs Energy consumption Greenhouse gasses Eutrophication Acidification Land Use Other Impacts Freshwater consumption Pesticides Antibiotics Soil Erosion
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Energy Consumed
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Greenhouse gases
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Eutrophication potential
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Summary of environmental impacts
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