Sustainability and Environmental Impacts of Food from the Sea

Ray Hilborn

School of Aquatic and Fishery Sciences University of Washington

Structure of talk

• This history of Gloom and Doom

• What the data tell us about status

• The environmental impacts of food from the sea

• Will not talk about economic status of fisheries or social impacts of fishing status and management

The history of Gloom and Doom

Science Magazine 1993

Fish stocks are inevitably overexploited before effective management is initiated

Pauly et al. (1998)

Global catch MTL Pauly’s 1998 Fishing down food webs

Nature 2003

All fish gone by 2048

What the public believes

• Most fisheries are unsustainably managed

• Stocks worldwide are declining

• The act of fishing destroys the environment

NCEAS working group: Finding common ground in marine conservation and management

Abundance trends of assessed stocks

1950 2000

Stock Size

Fish

ing

Pre

ssu

re

Maximum Sustainable Yield

Stock Size

Fish

ing

Pre

ssu

re

Fully Exploited

Overfishing

Under exploited

Overfished and

overfishing

Over fished

Stock Size

Fish

ing

Pre

ssu

re

Fully Exploited

Overfishing

Under exploited

Overfished and

overfishing

Over fished

Fro

m W

orm

et

al. 2

00

9

Stock Size

Fish

ing

Pre

ssu

re

Assessed stocks in industrial and developed countries

Fro

m W

orm

et

al. 2

00

9

Stock Size

Fish

ing

Pre

ssu

re

Assessed stocks in industrial and developed countries

Rebuilding Stocks

Problem Stocks

Fox model

Equilibrium biomass relative to MSY

Fre

qu

en

cy

0.0 0.5 1.0 1.5 2.0 2.5 3.0

05

10

15

20

25

Where we end up under current fishing pressure

Equilibrium biomass relative to BMSY

Above BMSY Sustainable

Big Problems

Were the Prophets of Doom correct?

• Ludwig Hilborn and Walters 1993

– For much of the world yes, overexploitation was the norm before management was imposed

– BUT there were exceptions,

– New Zealand and Alaska stand out as regions that absorbed the lessons of the rest of the world, and because they developed industrial fishing much later avoided any systematic overfishing

Current data

Pauly et al. (1998)

Branch et al. (2010) Nature 468:431-435

Global catch MTL Fishing down food webs

Demise of world tuna stocks

From Juan-Jorda et al. 2011. PNAS.

From Juan-Jorda et al. 2011. PNAS.

How have the successes been achieved

• A wide suite of “traditional” tools

– Catch limitation especially hard TACs

– Fleet reduction

– Area closures

– Gear restrictions

• There is no silver bullet

– Neither catch shares or MPAs have proved to be a necessary or sufficient condition

What about the rest of the world?

FAO SOFIA

0

10

20

30

40

50

60

0 5,000,000 10,000,000 15,000,000 20,000,000

% o

f st

ock

s o

vere

xplo

ite

d

2007 Catch (Tonnes)

Central and S. Atlantic, Mediterranean

NW Pacific

S.W. Pacific

Peru, ChileEuropeW. Indian Ocean

E. Indian Ocn

NW Atl

FAO regional analysis

These areas are all in better shape than reported by Worm et al. 2009 where we reported 2/3 stocks below BMSY

Gloom and Doom is real in some places

0

0.2

0.4

0.6

0.8

1

1.2

1975 1980 1985 1990 1995 2000 2005 2010

B/B

MSY

Unassessed stocks

Assessed Stocks

Costello et al. (submitted) status of major fish stocks

Summary of capture fisheries status

• Major industrial fisheries where we have assessments appear to be stable and mostly rebuilding because of reduced fishing pressure

• In some countries there remain many stocks with excess fishing pressure

• Major fisheries in the rest of the world on average have better or the same status, but appear to be declining. – No evidence of effective fisheries management

• Sustainability is a process, not a stock size

We can sustainably produce food from the sea

but at what environmental cost?

Science Magazine 2010

Measures of environmental impact

Inputs

• Energy

• Freshwater

• Fertilizer

• Pesticides

• Antibiotics

• Surface area impacted

Outputs

• Greenhouse gases

• Eutrophication potential

• Acidification potential

• Soil erosion

• Biodiversity loss

Energy intensity of food production

Crops Land animals Fish Pelletier et al. 2011. Ann Rev. Env. Resources

Environmental costs per 40g protein

Water (L)

Fertilizer (g)

Pesticides (mg)

Antibiotics (mg)

Soil Loss (kg)

Beef 2200 50 494 21 16

Chicken 1331 18 163 55 3

Pork 1331 46 422 53 8

Dairy 1178 34 299 50 7

Capture fisheries 1 0 0 0 0

Global Averages or combined studies where available

New Zealand dairy meat and fish compared to international

per 40 g protein

Energy MJ

Fresh Water (l)

Fertiliser (g)

Pesticides (mg)

Antibiotics (mg)

Surface area impacted (m2)

Greenhouse gasses (kg)

New Zealand Dairy

1.56 171 26

24

1.17 1.24

0.86

New Zealand Meat

4.90 262 188

129

1.17 18.14

3.70

International Dairy

3.62 Na Na Na Na 1.63

1.26

International Beef

10.86 Na Na Na Na 9.35

5.97

Squid

7.11 0 0 0 0 17

0.62

Hoki

7.31 0 0 0 0 100

0.64

From Hilborn and Tellier 2012

What about aquaculture?

Global warming potential T CO2/T bread wheat 0.8 oilseed rape 1.7 potatoes 0.24 tomatoes 9.4 beef 16 sheep 17 swine 6 poultry 5 bivalves 0.5

Eutrophication kg PO4 equivalent bread wheat 3.1 oilseed rape 8.4 potatoes 1.3 tomatoes 1.5 beef 160 sheep 200 swine 100 poultry 49 bivalves -4.9

Biodiversity impacts of capture fisheries, aquaculture, agriculture

• Capture fisheries are sustained by maintaining semi-natural ecosystems

• Agriculture relies on replacing natural ecosystems with highly productive exotic species

• Aquaculture falls somewhere in between

From Biodiversity in a forest-agriculture mosaic – The changing face of West African rainforests Ken Norris Biological Conservation 2010

My son modifying biodiversity

Organic vegetable field my wife farmed

Fisheries may have less biodiversity cost than organic agriculture

Some numbers easily found on the web

• 20.3 million tons of livestock production from grazing (Long shadow of livestock)

• 34 million km2 of land used for grazing (Long shadow of livestock)

• 0.6 tons/km • 81.9 million tons fish landed 2006 FAO 2008

• Would require 139 million km2 grazing lands • There are 6.2 million km2 of rainforest left

http://rainforests.mongabay.com/0101.htm

• Would need 22.3 times world rainforests area to replace world fish production by grazing at world average grazing productivity

Good citizens at work

Rapers and Pillagers of the environment

The environmental cost of precautionary marine conservation

• Many groups advocate precautionary marine conservation as an unqualified environmental benefit – Very low exploitation rates as seen in the U.S. – Closing large areas of the ocean such as the proposed

Coral Sea closure in Australia – Reduced harvesting of forage species

• There is a real net environmental cost – the lost food production will be made up by either clearing more land, or more intense use of irrigation, fertilizer and pesticides

Marine conservation tradeoffs The Orangutan equivalent

Close a forage fishery to save birds and mammals

• Peruvian anchovetta fishery 8 million tons

• 0.00115116 orangutan’s habitat lost per ton of palm oil produced

• Stopping forage fishing on Peruvian anchovetta would cost the habitat of 4,604 orangutans if the food energy of anchovetta was replaced with palm oil

Conclusion

• We do know how to sustainably manage fisheries in places with effective top-down governance – We need to apply the lessons learned to places that are slow to

change management

• But we need to understand carefully why fisheries are working in some places and not others, especially when we consider the economic and social dimension

• Many parts of the world either have not absorbed these lessons or lack the governance – But other tools are available

• Capture fisheries and aquaculture are a major part of global food security, and their environmental impacts should be compared to alternative forms of food production