Global Fish Stocks- a catastrophic and irreversible decline?Ashlee Maywald, Emily Megin,George River Ellis, Maverick Penman,Nompumelelo Mphele, & Patrick Ashton

How Did We Get This Far?A history of fishing and exploitation

Image: http://www.bbc.com/future/story/20120920-are-we-running-out-of-fish

The Global Decline• Globally stocks of fish have been rapidly falling since the

1980’s

Worm et al., 2006

Decline in Major Atlantic Fish• Salmon

1950’s: 10 8002010: 2 100 (20%)

• Cod1970’s: 300 0002010: 27 000 (10%)

• Tuna1950’s: 34 0002010: 9 600 (30%)

How Did This Happen?• Industrialisation

With increased technology catch efficiency has increased

• Misleading science• Optimism ☺

Image: http://www.portcastello.com/en/introduction/history/fishing-business-and-industrialisation.htmlImage: http://imgbuddy.com/fish-eggs-in-water.aspImage: http://amac.us/personal-story-optimism/

Where Are The Fish Coming From?● No more fish? Fish somewhere else!EU and USA make deals with poorer nations for the right to fish commercially in their water● Local and artisan

fishers are the usual losers○ They may catch only

⅓ of what they used to.

Image:http://www.marinelink.com/news/detained-fishing-trawler362553.aspx

The Tale of the North Sea

● Shallow, muddy and barren● Evidence of historical abundance of sturgeon, houting,

and bluefin tuna● Evidence of oyster reefs

Image: http://stock-clip.com/video-footage/sea+inhabitants/3

●Bottom trawling●Dynamite fishing of

coral reefs●Top-down environmental

alterations○Example: Norway cod

Habitat Destruction

Reduction of biodiversity

● Reduction of desired phenotypes○ selection on length-at-age○ selection on location

● Miniaturization○ earlier sexual maturity

Destabilization of the food chain

● Predator / prey interaction● Change in age structure

- Large reduction in biomass- Example: tiger flathead

Marine pollution●Anthropogenic●Alters reproductive systems●Disruption to coral reefs●Affects entire food chain

Solutions

Safe Catch Limits

http://qsr2010.ospar.org/en/media/chapter_pdf/QSR_Ch08_EN.pdf

Safe Catch Limitsneeds to be reassessed

regularlyscientifically determinedNOAA Magnuson

Stevens Fishery Conservation & Management Act (2007) http://wildliferesearch.org/category/overfishing/

Reduction of By-catch

http://www.biznews.com/green/2014/05/27/infographic-everything-need-know-bycatch/

http://www.underwaterbaitsetter.com.a u/bait-setter/the-baitsetter/

Gear Modifications

Catch Share Programs●holds fishermen individually responsible●helps in achieving safe catch limits●longer fishing seasonssafer work conditionsbetter management performance

http://www.edf.org/content_images/catch-shares-world-map-hi.jpg

http://www.edf.org/content_images/catch-shares-world-map-hi.jpg

Monitoring & Enforcement Approachenforcive legislationdata collection systemspatrol vesselsNew technology: satellite & infrared trackingsubregional & regional cooperation

http://voices.nationalgeographic.com/2014/01/30/shark-tagging-tracking-separating-fact-from-fiction/

http://www.gizmag.com/google-overfishing-global-fishing-watch/34794/

Marine Protected Areas

Success of MPAs in the past

Potential drawbacks of MPAs

Solution-based strategies

What are Marine Protected Areas?Marine protected areas (MPAs) are protected regions of seas, oceans or large

lakes; restrict human activity to protect natural or cultural resources.

MPAs and their restrictions differ substantially between nations:

development

fishing practices and gear

fishing seasons and catch limits,

moorings and bans on removing or disrupting marine life

Great Barrier Reef Marine Park Authority

The Arrabida Marine Park, PortugalTotal Protection

No fishing or recreational activities of any kind, navigation permitted

Partial ProtectionRestricted recreational activity permitted, sport

fishing forbidden, commercial fishing very limited

Complementary ProtectionSport fishing permitted, restricted commercial

fishing

Cunha et al. 2014

Improved catch

Cunha et al. 2014

MPAs implemented in 2005. Mean daily catch measured as kg per auction day. Increases significantly with MPAs.

CPUE for three different protection areas.

Implies a greater abundance of target species in areas of higher protection.

Cunha et al. 2014

Positive effects of MPAs Increase in trophic and functional diversity Increase in top predator abundance, decrease

in herbivore abundanceAbility to target key nursery/migration regions Spillover effects into neighbouring waters

Problems with MPAsLittle to no effect in areas of multiple

stable states (phase shifts)Effectiveness decreases as

migration of species increasesOpposition from local communitiesBureaucracy - planning,

maintenance, enforcement and review. $$$

Limited deterrence of overall fishing pressure in some areas

Worm et al. 2009

MPAs: Part of the solution

Rebuilding of Kenyan small-scale fishery with combination of measures

MPAs + gear restriction + community cooperation led to significant increase in commercial fishing value

Worm et al. 2009

Aquaculture ●How do we continue to meet the increasing

global demand for seafood?●Aquaculture: growing aquatic species under

controlled conditions●Real potential to reduce reliance on global

fish stocks

Forms of Aquaculture● Land Based: 60% fish products

● Brackish: 32% fish products

● Offshore: 8% fish products

(Biotechnology)

(Global fishing)

(fish site)

Inputs

●Food●Infrastructure●Operational energy

FoodFishmeal: - Comprised of processed pelagic fish:

Anchovy, Sardine, Capelin, Herring- Still marine Origins- Key pillar of many marine foodwebs

Outputs- Disease, disease deterrents- Escapees- Nutrients: uneaten foods, faeces

Management Framework- Antibiotic/parasiticide utilisation and

environmental toxicity- Pathogens & wild fish susceptibility - Fish escapees- Nutrient waste: food & faeces- Food sources

Used to maintain standards

Case Study - Offshore●Step 1:Public-Private partnership●Step 2: Construction:

(UNH.edu)

Fishmeal Research and Production Facility

●Explore use of alternatives to current protein sources

●Reduce reliance on pelagic fish species ●Trials: soya, insects, livestock carcases,

microalgae

Research ProjectsLarge scale so a number of small specific researches can be influenced with the $3 million used in different areas.

What is the importance of research and data?•Informs conservation management

•Effective Implementation of projects

•Increases capacity for research

•Clear results and direction from data

•Providing information

What Research projects have achieved•MPA’s and zones.•Safe catch limits.•Reduced bycatch•Reduced illegal fishing•Catch share programs•Effective aquaculture

http://www.un.org/apps/news/story.asp?NewsID=44250#.VVngUPmqqko

Proposed research projects•Satellite and infrared tracking illegal fishing activity

•Fishmeal research to improve Aquaculture

•Gear modification research to reduce bycatch

Satellite and infrared tracking illegal fishing activity

Expected results:Increased number of illegal fishing boats being intercepted

A more effective monitoring and tracking system

Deter illegal fishing

How this could inform management decisions:An improved way of tracking could lead to a broader use

more research enabling more detailed and informative systems

Fishmeal research to improve Aquaculture

Expected resultsFinding alternate fishmeal sources

Finding an environmentally economic and safe resource

How this could inform management decisions:Would not have to enforce as it is a cheaper resourceSustainable farming would benefit all parties involved

Gear modification research to reduce bycatch

Expected ResultsEffective modifications reducing bycatch

Reduced bycatch by up to 30%

How this could inform management decisions:Once proven effective it could then be applied to all fisheries using the same

technologyReduced bycatch makes fishing practices more efficient so would be in all

interests.http://www.nmfs.noaa.gov/by_catch/brep_2014_awards.html

Global fish stocks - a catastrophic and irreversible decline?

Fig 1: Worm et al. Average catch above, exploitation below Fig 2: Influence of Aquaculture up to 2005

http://marine.rutgers.edu/~ojensen/Documents/Worm_etal_2009_Science.pdf http://www.unep.org/dewa/vitalwater/article167.html

References· Clover, Charles (2006) The End of the Line: how overfishing is changing the world and what we eat. University of California Press, California, USACostello, C. et al. (2012) Status and Solutions for the World’s Unassessed Fisheries. Science 338: 517-520· Cunha, A. et al (2014) Biomares, a LIFE project to restore and manage the biodiversity of Prof. Luiz Saldanha Marine Park. J Coast Conserv 18: 643-655· Kurlansky, Mark (2011) World Without Fish: how could we let this happen? Workman Publishing, New York, USA“Dire Future for Fishing.” Reporter Greg Hoy. The 7:30 Report. Australian Broadcast Corporation, 5 May 2010. TV news. Web, 19 April 2015Takashina, N. & Mougi, A. (2014) Effects of marine protected areas on overfished fishing stocks with multiple stable states. Journal of Theoretical Biology 341: 64-70· Villamor, A., Becerro, M. (2012) Species, trophic, and functional diversity in marine protected and non-protected areas. Journal of Sea Research 73: 109-116· Voyer, M., Gladstone, W., & Goodall, H. (2014) Understanding marine park opposition: the relationship between social impacts, environmental knowledge and motivation to fish. Aquatic Conserv: Mar. Freshw. Ecosyst. 24: 441–462· West, C., Dytham, C., Righton, D., Pitchford. J. (2009) Preventing overexploitation of migratory fish stocks: the efficacy of marine protected areas in a stochastic environment. ICES Journal of Marine Science, 66: 1919-1930 Worm, B. et al. (2006) Impacts of Biodiversity Loss on Ocean Ecosystem Services. Science 314: 787-790· Worm, B. et al. (2009) Rebuilding Global Fisheries. Science 325: 578-585