What Happened?
• Winner's strategy
• Optimal individual strategy
• Optimal group strategy
• Resource behavior
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 1
Summary of Company Performance
Year
2
Year
3
Ships
Ships
Year
4
Ships
Year
5
Ships
Year
6
Ships
Year
7
Ships
Year
8
Ships
Company
Assets
1
2
Assets
Assets
Assets
Assets
Assets
Assets
Year
9
Grand
Total
5/1000
7/1500 11/1110
14/3010 22/100
22/-400
22/-1100
4400
5/1000
10/790 10/2390 13/4670 18/820
18/-660
18/-1170
3330
5/1000
10/790
17/3220
17/3100
7350
17/100
17/4260 17/3230
Year
10
Ships
Assets
Year
Ships
Assets
3
5/1000
8/800
5/1000
12/90
10/1060 17/1940 24/-2650
24/-5980 24/-7470
-1470
4
24/-1730 32/4830 44/-4240 44/-10830 44/-14200
-3200
5
6
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 2
1
Summary of Game Behavior
10
9
8
7
I
N 6
D 5
E
X 4
3
2
1
0
1
2
3
4
5
6
7
8
9
10
YEAR
FISH
FISH
Fish Banks, Ltd. © 2001 Dennis L. Meadows
SHIPS
BOATS
CATCH
CATCH
D 3
Typical Game Behavior
Fish
Catch
Ships
0
1
2
3
4
5
6
7
YEAR
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 4
Typical Game Behavior – Fleet
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 5
Typical Game Behavior – Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 6
Typical Game Behavior – Fish Population
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 7
Aggressive Strategies
“Purchase many boats until average fish productivity starts to
decline. When fish productivity goes down, fish other areas.”
“Increase fleet size as long as yields are stable.”
“We will continue to add at least 1 ship per year. We will fish
in both the deep sea and coast depending on fish supplies…”
“We have acted on an impulse that things will be good for a
few more years. Probably will keep our fleet at or around this
size [16 boats].”
Comments from students at the University of New Hampshire.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 8
Conservative Strategies
“We want to keep our fleet at this constant level and disperse
it so as not to deplete fish resources in the deep sea and
coast. “
“Buy conservatively, out of necessity, and keep our bank
balance positive.“
“Obtain a stable fleet size [and] move fleet around to follow
fish population densities. Sell off some of fleet as time goes
on.”
Comments from students at the University of New Hampshire.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 9
Does fish depletion happen in real life?
• Pacific Sardine
• Peruvian Anchovy
• North Sea Herring
• Atlantic Swordfish
• Atlantic Cod
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 10
Pacific Sardine Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 11
Peruvian Herring, Anchovy and Sardine Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 12
North Sea Herring Catch
Source: Nichols, John. “Saving North Sea Herring.” Fishing News February 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 13
Atlantic Swordfish Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 14
Atlantic Cod Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 15
Principal Global Oceanic Fisheries
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 16
Total World Fish Catch
Source: Fisheries of the United States, US Dept. of Commerce, 2000.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 17
How The World’s Fish Are Caught
Currently there are some 13 million fishers in the world. Twelve
million use simple traditional technologies to land about half the
world’s fish catch. The remaining one million fishers crew 37,000
industrial fishing vessels and account for the other half of the fish
caught. These fishers deploy highly sophisticated contrivances
ranging from sonar and spotting planes to fishing nets large enough to
swallow twelve 747 jumbo jets.
Source: “World Fisheries in Crisis.” Environmental News Network July 10, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 18
The World’s Fisheries – Anarchy
“The emerging anarchy in the oceans” is how one United
Nations official describes the situation on the high seas. With
so many vessels scouring increasingly fished-out waters,
squabbles are inevitable. Russians attack Japanese vessels in
the Northwest Pacific. Scottish fishers attack a Russian trawler.
A Falkland Islands patrol chases a Taiwanese squid boat more
than 4,000 miles. Norwegian patrols cut the nets of three
Icelandic ships in the Arctic, and shots are exchanged.
Philippine patrols arrest Chinese fishers near the hotly
contested Spratly Islands in the south China Sea. The list of
confrontations is ever-expanding.
Source: “World Fisheries in Crisis.” Environmental News Network July 10, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 19
Global Fisheries Depletion
Thousands of Tons
Potential
Region
Species
Northwest Atlantic
Cod
Haddock
Capelin
Herring
1,350
100
500
300
48
7
2
243
1,302
93
498
57
Northeast Atlantic
Herring
2,250
1,643
607
Southeast Atlantic
Pilchard
600
210
390
Northwest Pacific
Salmon
350
367
-17
Northeast Pacific
Halibut
Perch
King Crab
38
210
40
32
26
5
Southeast Pacific
Anchoveta
Total
1994 Catch
Loss
6
184
35
9-11,000
11,897
- 897
16,738
14,480
2,258
Source: The State of World Fisheries and Aquaculture. United Nations Food and Agriculture
Organization, 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 20
International Fisheries Management
The relative failure of international management to
establish sustainable fisheries in many areas, despite
the high quality of the research base sometimes
provided, is clearly demonstrated by the dwindling
resources, excessive catching capacity, uncontrolled
transfers of fishing effort between resources and
oceans, and depletion of many highly valuable
resources...The fact that uncontrolled development of
fishing effort leads to disaster has now been widely
acknowledged in the scientific literature, and by
high level fisheries management and development
authorities.
Source: Roodard. Review of the State of World Fishery Resources. Agriculture of the
United Nations. Rome 1990.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 21
Where else does depletion occur?
• Groundwater
• Forests
• Soil
• Game Animals
• Ozone
• Other Renewable Resources
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 22
The Fisheries System
• Principal interactions
- Fish/Regeneration
- Fish/Catch
- Catch/Investment/Ships
• Other influences
- Auction
- Environment
- Price
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 23
The Fisheries System: Fish
REGENERATION
,
+-
(+-, )
+
DENSITY
Fish Banks, Ltd. © 2001 Dennis L. Meadows
+
FISH
TOTAL
CATCH
D 24
The Fisheries System: Catch
CATCH
FISH
FISH
PRICE
+
DENSITY
+
+
-
INCOME
+
+
+ +
SHIP
OPERATING
COSTS
(-)
DESIRED
GROWTH
TOTAL
CATCH
+ CATCH PER
-
PROFIT
(-)
+
SHIPS
-
(+) +
INVESTMENT
+
Fish Banks, Ltd. © 2001 Dennis L. Meadows
PURCHASE AND
CONSTRUCTION
COSTS
D 25
The Fisheries System: Investment
(+)
FISH
PRICE
TOTAL
CATCH
+
+
INCOME
+
+
-
PROFIT
+
OPERATING
COSTS
(-)
DESIRED
GROWTH
+
SHIPS
+,-
(+) +
-
INVESTMENT
+
Fish Banks, Ltd. © 2001 Dennis L. Meadows
PURCHASE AND
CONSTRUCTION
COSTS
D 26
The Fisheries System Structure
(+)
REGENERATION
,
+-
FISH
DENSITY
(-)
FISH
PRICE
+
+
INCOME
+
+
+ +
OPERATING
COSTS
+
SHIPS
+,-
(+) +
TOTAL
CATCH
SHIP
(-)
DESIRED
GROWTH
-
+ CATCH PER
-
PROFIT
+
(+-, )
+
-
INVESTMENT
+
Fish Banks, Ltd. © 2001 Dennis L. Meadows
PURCHASE AND
CONSTRUCTION
COSTS
D 27
What else affects the fisheries system?
• Foreign competition
• Technology
• Regulation
• Pollution
• Weather (El Nino)
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 28
Impact of Technology on Ship Effectiveness
HIGH TECHNOLOGY
CATCH
PER
SHIP-YEAR
LOW
TECHNOLOGY
0
0
Fish Banks, Ltd. © 2001 Dennis L. Meadows
FISH
DENSITY
MAXIMUM
D 29
Is there anything wrong with depletion?
• Present value of the fishery
• Local vs. global strategies
• Impacts on linked ecosystems
• Equity of resource distribution
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 30
Dietary Importance of Fish
In all, marine and inland fisheries provide nearly
30 percent of Asia’s animal protein, in Africa the
proportion is 21 percent, in Latin America 8
percent.
Source: Fisheries at the Limit. 1993.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 31
What can be done?
• Partition the seas
• Establish quotas
• Farm fish
• Move down food chain
• Change consumption preferences
• Reduce destruction and pollution of fisheries
• Limit ship fleets, technology
• Develop better methods for stock assessment
• Change social values and economic incentives
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 32
Alternative Catch Policies
-
Maximum
Sustainable
Catch
CATCH
-
3
2
1
-
TIME
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 33