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
BOATS
SHIPS
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
Inconsistent Goals and Strategies
“We would like to keep our operating costs down and not
deplete our resources. We want to save money so that we can
buy more ships in the next couple of years.”
“We will expand our capacity … when fish population is
high … but we must not be over-anxious so that we can
make a secure future for ourselves, the environment, and
those who need to eat the fish.”
Comments from students at the University of New Hampshire.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 10
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 11
Pacific Sardine Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 12
The Pacific Sardine Fishery
“The Pacific Coast sardine industry had its beginnings back in 1915
and reached its peak in 1936-1937 when the fishing netted 800,000
tons. It was first in the nation in numbers of pounds of fish caught, and
ranked third in the commercial fishing industry, growing $10 million
annually. The fish went into canned sardines, fish bait, dog food, oil,
and fertilizer. The prosperity of the industry was supported by
overexploitation. The declines in the catch per boat and success per
unit of fishing were compensated for by adding more boats to the
fleet. The fishing industry rejected all forms of regulation. In 19471948 the Washington-Oregon fishery failed. Then, in 1951, the San
Francisco fleet returned with only eighty tons. The fishery closed
down…”
Ecologist Robert Leo Smith
Source: Owen, Oliver. Natural Resource Conservation: An Ecological Approach. New
York, N.Y.: MacMillan, 1985.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 13
Pacific Sardine – Boom-and-Bust Cycles
California’s Pacific sardine abundance has gone through boom-and-bust
cycles. The decline of the resource, from a biomass of more than 3,000,000
tons in the 1930’s to immeasurable low levels (a few thousand metric tons) in
the 1970’s, stimulated much debate as to whether fishing or an adverse natural
environmental period was to blame…
Coastal pelagic fishes such as the sardine show natural long-term fluctuations
of very large amplitude, presumably in response to decadal-scale warm and
cold ocean regimes. During warm periods, the populations can withstand high
fishing rates, but during cold periods they decline even in the absence of
fishing ... When the ocean entered a cold regime in the 1940’s, continued
heavy fishing accelerated the otherwise natural decline and drove the sardine
population to an extremely low level, hindering recovery once conditions
warmed and became favorable again beginning in the late 1970’s.
Source: Marine Resources. National Marine Fisheries Service. NOAA, U.S. Dept. of
Commerce, 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 14
Pacific Sardine – Officially Recovered
The sardine resource off California has surpassed a million tons
and is now (January 15, 1999) considered fully recovered for the
first time since the heyday of Cannery Row in the mid-1940’s…
At an interagency Pacific sardine workshop held in 1983, it was
agreed that the sardine population would be considered fully
recovered when it reached a million tons, occupied its historic
range (Mexico to Canada), and all historic age classes were
represented in the population. All three of these criteria have now
been met, representing a real success story for Pacific sardines and
marine fishery managers.
Source: Hill, Dr. Kevin. CA Department of Fish and Game. January 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 15
Peruvian Herring, Anchovy and Sardine Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 16
Peruvian Anchovy Fishery – Collapse
The collapse of this anchovy fishery, once the world's
largest, has been costly. Peru lost two export commodities –
the fish meal and the guano from sea birds that depend on
anchovy – that once dominated its foreign-exchange
earnings. When this fishery was at its peak in 1970, exports
of its products earned Peru $340 million, roughly a third of
its foreign exchange. The disappearance of this vitally
needed source of hard currency contributed to the growth of
Peru's external debt; in the mid-eighties over 40 percent of
the nation's exports are required merely to service its
outstanding loans. And the world has lost a major protein
supplement, once used in rations of hogs and poultry.
Source: Lester Brown, et.al. State of the World 1985. New York, N.Y.: W.W. Norton & Co., 1985.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 17
Peruvian Fishery and El Nino
Off the coast of Peru lies one of the most productive
fishing areas in existence. The coastal upwelling in
this region is the result of deep oceanic currents
colliding with sharp coastal shelves forcing nutrient
rich cool water to the surface….
These currents occasionally change direction in what is known as an
El Nino…. When these irregular current changes take place the
surface temperature of the water rises and the nutrient rich
environment which promotes an abundance of sea life disappears.
Coping with these irregular cycles and the problem of harvesting
threaten the Peruvian anchovy industry, as well as the related guano
industry.
Source: Lee, Dr. James. “Peruvian Anchovy Case.” American University, Washington, D.C.: n.d.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 18
North Sea Herring Catch
Source: Nichols, John. “Saving North Sea Herring.” Fishing News February 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 19
North Sea Herring – Collapse
The reasons for the failure (in the 1970’s) have been
attributed both to high mortality of the juveniles in the North
Sea industrial fisheries, and to heavy fishing by bottom
trawlers on the spawning concentrations…
Bottom trawling on the spawning grounds not only disturbs
spawning fish but also destroys the spawn and damages the
substrate on which successful spawning depends.
Source: Nichols, John. ”Saving North Sea Herring.” Fishing News February 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 20
North Sea Herring – Management
We are not dealing with a single stock in the North Sea but a
complex of three separate stocks each with separate spawning
grounds, migration routes and nursery areas… In spite of the
separate spawning areas, the adults and juveniles mix and are
caught together in the central North Sea fisheries. Therefore,
North Sea…herring have to be managed as a single unit
because the catches cannot be apportioned to the separate
stocks.
Stock assessment and management is further complicated by
the fact that five separate types of fisheries exploit North Sea
herring. Only two of these fisheries are in the North Sea – the
others are in the nursery areas…
Source: Nichols, John. ”Saving North Sea Herring.” Fishing News February 1999.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 21
North Sea – Changes to the Ecosystem
Within the ecosystem, the fish serve as a keystone,
critical link, in marine food chains. Excessive
removals of fish can have dramatic effect...
In the North Sea, east of Great Britain...the
removal...through intensive fishing...of
millions of metric tons of herring and mackerel...
depleted the stocks...the small fast-growing sand
eel population exploded...
Source: "Where Have All the Fish Gone?" Nor Easter Fall/Winter 1990.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 22
Atlantic Swordfish Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 23
Atlantic Swordfish – Decline
…between 1989 and 1996 East Coast swordfish landings
plummeted almost 60 percent (from about 11.3 million to
4.9 million). Earnings plunged from almost $36.5 million
to just over $17.6 million. Meanwhile, the number of
longline hooks set in the Atlantic increased 70 percent
between 1987 and 1998… And that was just from
American boats…
Source: Benchley, Peter. “Swimming With Sharks.” Audubon May-June 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 24
Atlantic Swordfish – Impact
“Ten or fifteen years ago, I’d commonly find two-hundred
pound swordfish in the market,” chef Will Tracy, told me.
“Now they’re so small they have new names: between fifty
and a hundred pounds, they’re called dogs; from twentyfive to fifty, pups; under twenty-five, rats. One day I saw a
shipment of swordfish… It had maybe two hundred fish
that were no bigger than fifteen pounds each. I find that
very disturbing.”
Source: Benchley, Peter. “Swimming With Sharks.” Audubon May-June 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 25
Atlantic Cod Catch
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 26
New England Fisheries – Good Times
14 years ago, fisherman Peter Morse remembers a
feeling that the bounteous ocean could never run out
of fish. Fishing, another fisherman told him, was “like
going to the bank and making a withdrawal.”
“When they established the 200 mile limit in ‘76 and
kicked all the foreigners out, it was ‘Hooray, let’s git
‘em!’ just like Gold Rush days,” said Morse, a
longtime gillnetter.
Source: Kittredge, Clare. "N.H. Fish Story Is Not a Happy One." Boston Globe February 4, 1990.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 27
New England Fisheries – Hard Times
“Fish are in trouble off our nation’s coasts… Among
the most troubled are the fabled cod in the Gulf of
Maine.”
“For nearly a decade, cod stocks here have remained at
near-record lows despite major repair efforts,
including a $25 million government buyout that
shrank the size of the fishing fleet by 79 vessels; the
closure of a 5,000-square-mile area of the Gulf of
Maine and adjacent Georges Bank to all bottom
fishing; and, at one point, limiting an individual
fisherman to 30 pounds of cod-just two or three fish,
on average – per trip.”
Source: ”Are We Running Out of Fish?" Consumer Reports Online February 2001.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 28
Canadian Cod Fishery – Hard Times
“Bad as the situation is here, it’s worse in Canada.
There, the cod population crashed so completely that
an eight-year-long total ban on cod fishing has failed
to bring it back.”
“The scope of this disaster is economic as well as
environmental, conservationists and economists say.
The disappearance of cod and other species from the
Grand Banks has left some 50,000 Canadian
fishermen and fish plant workers unemployed.”
Sources: “Are We Running Out of Fish?" Consumer Reports Online February 2001.
Givlio Pontecorvo. “Depletion of Ocean Fisheries.” April 1995.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 29
Canadian Cod Fishery – Reactions
“The cod are gone, and a way of life is also
vanishing…fishermen whose pride and identity – as much as
their livelihoods – were derived from the sea… don’t dare to
speak of utmost despair, only of their rage.”
“Those fish are coming back, and I’ll be waiting on this
shore by God. Doesn’t matter if I survive on nothing but tea,
molasses, and white bread in the meanwhile. The cod are
coming back someday.”
Source: Nickerson, Colin. “Newfoundland, Farewell.” The Boston Globe Magazine
September 20, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 30
New England Fisheries – Human Cost
Today, fishing specialists say they see old-timers who used to
go day-fishing two-by-two taking the risk of going alone, going
without insurance, and skimping on boat maintenance, going
farther and farther from shore, sometimes several days in
marginal weather.
“The guys’re trying to pay off boats and … fuel bills and it’s
dangerous,” said Marconi [head of the New Hampshire
Commercial Fishermen’s Association]. “If they’re alone and
they get caught in a winch…”
Source: Kittredge, Clare. "N.H. Fish Story Is Not a Happy One." Boston Globe February 4, 1990.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 31
Newfoundland’s Fishery Collapse – Human Cost
MacKay was doing something she had never done,
never dreamed of doing; leaving the Rock. Quitting
Newfoundland. Turning her back on the island where
she’d been born, schooled, and married, worked as a
fish packer, brought her babies into the world… “it’s
a scary thing, saying goodbye to people you’ve known
every day you’ve breathed. I’m already homesick,”
she says. “But the fishery’s done, and we’ve got to
find a life.”
Source: Nickerson, Colin. ”Newfoundland, Farewell." The Boston Globe Magazine
September 20, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 32
New England Fisheries – Yields Declining
“The waters off the coast of New England are
considered some of the most fertile and productive
in the world. But too many boats have chased too
few fish...leading to dramatic declines...Today the
sea yields (less then) 24,000 metric tons of fish
compared with 574,000 tons in 1965.”
Source: "New England Tradition Gets Caught in A Net." Boston Globe June 1992.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 33
New England Fisheries – Impact
“Technology, capital invested in boats and gear, and openended competition have destroyed most of our fisheries,”
says Peter Shelley, director of the Maine Office of the
Conservation Law Foundation.
Source: ”Are We Running Out of Fish?” Consumer Reports Online February 2001.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 34
New England Fisheries – Losses
“[Haddock, cod, and flounder] made up 75 percent
of the catch in the early 1960s, but overfishing has
shifted the populations so that now 75 percent of
the catch is ‘trash fish such as dogfish and skate,’
said Bill Woodward, an aide to Senator John Kerry.
A 1990 report estimated the annual losses to New
England because of depleted groundfish stocks at
$350 million in gross income and 14,000 jobs.
Source: "Scientists: A Better 'Big Picture’ Needed to Save Ocean Habitat." Boston Globe
June 1992.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 35
New England Fisheries Management I
Politicians blame marine scientists for the collapse of
the cod, saying the stocks were mismanaged. The
scientists blame their bureaucrat bosses, who they say
ignored the scientific warnings that the stocks were in
dire shape. Bureaucrats blame the politicians for
making short-term employment of fishermen the
political priority, not long-term protection of a vital
ocean resource. And everyone blames the fishermen
for going and doing what they were urged by
politicians, scientists, and bureaucrats to do – catch
more fish for the greater good of the Newfoundland
economy.
Source: Nickerson, Colin. ”Newfoundland, Farewell." The Boston Globe Magazine
September 20, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 36
New England Fisheries Management II
...The Conservation Law Foundation's...suit against the federal
government has forced new regulations intended to drastically
reduce the numbers of fish harvested in New England waters...
Under new laws that started taking effect March 1, 1994
fishermen will be forced to reduce their time at sea by half – in
increments of 10 percent a year over at least five years.
... fishermen say a livelihood that has been a part of New
England tradition will be in danger of extinction. “What are we
preserving the stock for, if you’re going to put the fishermen out of
business?” asked Tony Verga, executive director of the
Gloucester Fisheries Commission.
Sources: Nickerson, Colin. "Stripping the Sea's Life." Boston Globe, April1994.
"Plenty of Fish in the Sea? Not Anymore." New York Times March 1992.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 37
New England Fisheries Management III
… The National Marine Fisheries Service’s task is to
enforce a federal law, the Magnuson-Stevens
Fisheries Act, passed in 1976 and strengthened in
1996, which specifies that the nation’s fish stocks
must be brought back to a “sustainable” level – a level at which
they reproduce faster than they’re caught...
(They) have a long way to go: According to the best
estimates, nearly half the stocks of fish caught in U.S.
waters and by American fishing boats in international
waters are so heavily fished they can’t reproduce fast
enough to prevent their … decline.
Source: “Are We Running Out of Fish?” Consumer Reports Online. February 2001.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 38
New England Fisheries Management IV
The federal government delegates most regulatory
decisions to eight regional fishery-management
councils, made up mainly of representatives from
the fishing industry and government, with others
from environmental and consumer groups. The
result is a crazy-quilt of local regulations that vary
enormously in details – and success – from one
region to the next.
Supporters of the system say it’s fair because
decisions are made by the people most directly
affected – the fishermen themselves. Critics say the
fox is guarding the henhouse.
Source: “Are We Running Out of Fish?” Consumer Reports Online. February 2001.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 39
Canadian Fisheries Management
Ottawa’s response to the fisheries crisis has resulted in perhaps the
worst political fiasco in modern Canadian history. In the past four
years, the government has pumped a stunning $1.5 billion into
something called the Atlantic Groundfish Strategy. In theory, the
program was meant to retrain fishermen for other jobs while buying
up their licenses and craft, thus ensuring that if the cod ever did come
back, there would be far fewer fishermen demanding quotas.
In reality the effort has become a thinly disguised welfare program…
The program is fast running out of money. Fishermen were unamused
to learn recently that the final $300,000 in the pipeline will be used to
train program staff in how to handle the violence that could erupt
when the funding dries up and fishermen are left with nothing but
their worthless gear.
Source: Nickerson, Colin. ”Newfoundland, Farewel.l" The Boston Globe Magazine
September 20, 1998.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 40
Principal Global Oceanic Fisheries
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 41
Total World Fish Catch
Source: Fisheries of the United States, US Dept. of Commerce, 2000.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 42
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 43
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 44
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 45
U.S. Fisheries Management – Social
“There is no economic reason for keeping such
large fleets in business,” says David Die, stock
assessment expert at FAO. “The overriding reason
for them is social. Closing down some fisheries
would lead to massive unemployment.”
Source: "Waves of Anger Spreading Through the World's Oceans." Guardian Weekly April 1993.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 46
U.S. Fisheries Management – Economic
A major reason for the poor state of U.S. fisheries...is
the councils' tendency to set catch levels that are
more attuned to the economic needs of fishermen
than to the long-term conservation of the stocks.
Source: "Restoring Fisheries Poses Threat to a Way of Life." Washington Post February 1992.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 47
U.S. Fisheries Management – Political
Fish don't vote, but fishermen do.
Source: "Restoring Fisheries Poses Threat to a Way of Life.” Washington Post February 1992.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 48
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 49
Where else does depletion occur?
• Groundwater
• Forests
• Soil
• Game Animals
• Ozone
• Other Renewable Resources
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 50
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 51
The Fisheries System: Fish
REGENERATION
,
+-
(+-, )
+
DENSITY
Fish Banks, Ltd. © 2001 Dennis L. Meadows
+
FISH
TOTAL
CATCH
D 52
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 53
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 54
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 55
What else affects the fisheries system?
• Foreign competition
• Technology
• Regulation
• Pollution
• Weather (El Nino)
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 56
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 57
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 58
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 59
Present Value of the Fishery
The maximization of the present value of the fishery by employing an
optimum dynamic strategy need not but can imply extinctions of the
fishery. Does this mean that economists would recommend the
extinction of fish species under appropriate market conditions? Social
decisions take place in a multiple-objective or multiple-criterion
framework of which economic net benefits are but one criterion. The
responsible economist would generate information on the present
values of the fishery under different schemes of management. If the
highest present value of net benefits appears to be generated by a
pattern of fishing that eventually would exterminate the fish stock, this
would be stated, along with the information on other schemes that
would preserve a viable fish stock. The decision makers then would
understand the tradeoffs involved and could proceed with their
decision.
Source: Charles W. Howe. "The Management of Fisheries." Natural Resource Economics.
John Wiley & Sons: 1979.
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 60
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 61
Alternative Catch Policies
-
Maximum
Sustainable
Catch
CATCH
-
3
2
1
-
TIME
Fish Banks, Ltd. © 2001 Dennis L. Meadows
D 62