Mid-Term Study Guide

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Transcript Mid-Term Study Guide

OCN331 / MARE360
Our Objective:
Insights for Your Lifetime
OCN331 / MARE360
• How do the oceans make fish?
• How do we extract fish from the oceans?
• What other living resources do the world’s
oceans hold?
• Why do we care?
Social
Concerns
Information
Quality
Natural
Variability
Some Wind and Current Fundamentals
I. Effect of Differential Heating on Atmospheric
Circulation
II. The Coriolis Effect
III. Trade Winds and Westerlies
IV. Air-Sea Interactions
V. El Niño
Some effects of atmospheric circulation cells
Dry climate and high pressure in the
vicinity of 30o latitude
Wet climate and low pressure in the
vicinity of the equator and 60o
latitude
Bermuda: 32.3 N
Honolulu: 21.3 N
There are five major coastal upwelling regions in the world, along the
coasts of California, Namibia, Mauritania, and Somalia.
Effects of Walker Cell circulation
Wet climate and low pressure at the western
margin of the ocean basin near the equator
Dry climate and high pressure at the eastern
margin of the ocean basin near the equator.
Things to Remember
I. High atmospheric pressure at 30° N and 30° S
latitude governs major wind patterns
II. The Coriolis Effect deflects winds and currents
to the RIGHT in the Northern Hemisphere
and to the LEFT in the Southern Hemisphere
III. These wind and current phenomena generate
coastal UPWELLING of deep ocean water
IV. Variations in the strength of these winds and
currents can lead to conditions (EL NIÑO)
that disrupt upwelling
Hugo Grotius
Mare Liberum
1609
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Whales
Norwegian herring
Japanese sardine
Peruvian anchovy
Can. N. Atlantic cod
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Technology
Capital Investment
Fisheries Information
Politics
Social Issues
Tragedy of commons
Population
Total Global Fisheries Harvest ~160Mt
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Year
2002
2003
2004
2005
2006
CAP
94.5
91.8
96
95.5
93.1
AQ
52
55.2
60
63.3
66.7
• Capture Fisheries are
constant at ~90-95Mt
• Aquaculture is
steadily increasing
Disposition of the total aquatic catch for 2002
Use
% of total (by weight)
Human consumption
75.8
Fresh
39.7
Frozen
20.0
Cured
7.3
Canned
8.7
Reduction
19.0
miscellaneous
5.3
Why Do We Care?
• Calories
• High Quality Protein
• Essential Amino Acids
• Essential Fatty Acids (PUFA’s)
EPA & DHA Content of Fish
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Cod
Flounder
Mackerel
Pollock
Salmon, farmed
Shrimp
Trout
Tuna, bluefin
Tuna, canned
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0.13
0.43
1.57
0.46
1.83
0.27
0.80
1.28
0.73
Proper Growth and Development
of Children
• Omega-3s and pregnancy
– During last trimester of pregnancy
• Rapid synthesis of brain tissue
• Omega-3s and premature infants
– Risk factor for preterm delivery and
low birth weight
• Omega-3s and the newborn
– DHA is influenced by the mother’s diet
21
ω3 Fatty Acids & Fetus Health
• “Fish is Brainfood”
• EPA & DHA (from week 20)
• Important for Infants’
– Nerve, Visual, Immune system development
– DHA Supplements Breast Milk & Formulas
Important for Infants’ Intellect
-IQ-fish consumption correlation
How the Oceans Make Fish
• Primary Production  Commercial Fish
• 3 Types of Ocean Areas
– Open Ocean
– Coastal Areas
– Upwelling Areas
Open Ocean Area
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Deep
Low inputs
Mostly Regen. Nutrs.
Stable Temporally
Nutrient Limited
• Small Phytoplankton
• Long Food Chains
• Low Comm.Fish Yield
Coastal Areas
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Shallow
Seasonal Inputs
Seasonal Variability
~50% New Nutrients
• Larger Phytoplankton
• Shorter Food Chains
• Benthic Food Chains
• Gadoid fishes
• High Comm. Fish
Yield
Upwelling Areas
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Shallow
Seasonal Inputs
Seasonally Steady
Mostly New Nutrients
• Larger Phytoplankton
• Short Food Chains
• Clupeid fish
• High Comm. Fish
Yield
Harvesting
• How it’s done
• What’s caught
• Changes over time
Old & New Methods
• Spear
• Hook-n-line
• Traps
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Exploding harpoon
Trolling
Trolling-n-chumming
Demersal Trawl line
Pelagic Trawl line
2000 hooks; 3-4%
Traps
FADs
Nets
• Gill Nets
• Floats & weights
• Drift nets
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Efficiency
Fiber advances
Bycatch
33000km—80%
Banned in 1992
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Trawl Nets
demersal & pelagic
Power needed
Beam
beam  Otter
10-100m opening
Echo-sounder
sonar
Table 2.2 Major species of fish caught with otter trawls
Species
Major fishing countries
Areas fished
Alaska pollock
Russia, Japan, South Korea
Northwestern
Pacific
USA
Northeastern
Pacific
Atlantic cod
Iceland, Norway, Russia
Northeastern
Atlantic
Blue whiting
Norway, Iceland, Russia,
Faeroe Islands
Northeastern
Atlantic
Largehead hairtail
China, South Korea
Northwestern
Pacific
Purse Seines
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Globally, most fish catch…by far
Catch fish schooling near surface
100km x 100m
Fish must aggregate in large schools
Powerful means to deploy & retrieve
Dories (50’s) to power block
Table 2.1 Major species of fish caught with purse seines
Species
Major fishing countries
Areas fished
Atlantic herring
Canada, USA,
Northwestern Atlantic
Denmark, Iceland, Norway
Northeastern Atlantic
capelin
Iceland, Norway
Northeastern Atlantic
Chilean jack mackerel
Chile, Peru
Southeastern Pacific
Chub mackerel
China, South Korea, Russia
Northwestern Pacific
Chile
Southeastern Pacific
European pilchard
Morocco
East Central Atlantic
Japanese anchovy
China, Japan, South Korea
Northwestern Pacific
Peruvian anchovy
Peru
Southwestern Pacific
Skipjack tuna
Indonesia, Taiwan, Japan, South Korea,
Philippines, USA, Palau
West central Pacific
Ecuador
Southeastern Pacific
Japan
Northwestern Pacific
Spain, Maldives
Indian Ocean
Philippines, Taiwan, Japan, USA
West Central Pacific
Mexico, Venezeula
East central Pacific
Ecuador
Southeastern Pacific
France
Western Indian
Yellowfin tuna
Catch Amount by type
• Purse Seine
~50%
– Herring,sardine,anchovies,tuna,mackerel
• Otter Trawl
~17%
– Pollock, cod,whiting
• Lines
~ 9%
– Tunas,swordfish,cod,halibut,haddock,etc
• Pound/trap nets
– Lobsters,crabs
• Gill Nets
~6%
– Squid,salmon,billfish
~8%
OVERVIEW OF WORLD FISHERIES
I. Reporting and Measurement Issues
II. Major Fisheries - By Fish
III.Major Fisheries - By Nation
IV.Major Fisheries - By Ocean
V. Economic Values
II. Major Fisheries - by Fish
THE FIRST TIER
• Peruvian Anchovy
• Alaskan Pollock
• Skipjack Tuna
• Capelin
Peruvian Anchovy
• Not heavily fished until the 1950s
• By 1970, the largest fishery in the world
• Susceptible to disruptions by ENSOs
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Lessons may have been learned
Alaskan Pollock
• Not heavily fished until the 1960s
• Improvements in processing ability
were important
• Overfishing a real concern
• Monitoring and managing techniques
may be improving
Skipjack Tuna
• Another recently developed fishery
• Catches are trending upwards
• This resource may be underutilized
• Monitoring and managing techniques
are a challenge
Capelin
• Yet another recently developed fishery
• An early peak, a characteristic of
some new fisheries
• An equlibrium may be being attained
• This fishery is dominated by two
relatively cooperative countries
II. Major Fisheries - by Fish
THE SECOND TIER
• Atlantic Herring
• Japanese Anchovy
• Chilean Jack Mackerel
• Blue Whiting
III. Major Fisheries - by Nation
THE FIRST TIER
• China
• Peru
• United States
• Indonesia
III. Major Fisheries - by Nation
THE SECOND TIER
• Japan
• Chile
• India
• Russia
IV. Major Fisheries - by Ocean
Atlantic
25.6%
Pacific
62.6%
Indian
10%
Other
1.7
Percentages of global marine capture fishery production accounted by regions of the ocean
Fishing area
Atlantic
% global capture production
25.6
Northwest
2.4
West central
2.1
Southwest
2.7
Northeast
12.7
East central
4.1
Southeast
1.6
Pacific
62.6
Northwest
26.9
West central
11.5
Southwest
0.9
Northeast
2.9
East central
2.0
Southeast
Indian
18.4
10.0
East
5.5
West
4.5
V. Economic Values
Fish eaten by humans have high market value
Fish used for reduction have low market value
Reasons to Fish Below the MSY
I. Inaccurate Information
A. I Fish Therefore I Lie (Schaefer Model)
B. Not Enough Biological Data (Beverton-Holt Model)
II. Variable Recruitment
III. Resource Mismatch
IV. Presence of Competitors
V. Stock Stability
VI. Economics (Law of Diminishing Returns)
I. T
Stock Stability
Fishing at 15% of MSY
Fishing at 75% of MSY
Fishing at 100% of MSY
Schaeffer Model
Requirements:
Measurement of Fish Caught
Measurement of Fishing Effort
Beaverton-Holt Model
Requirements:
Measurement of Fish Caught
Knowledge of Fish Biology
Population Size (Tagging)
Age (Otoliths)
Reproductive Biology
Beverton-Holt Model:
Application to a Resource-Limited Population
Mortality declines with
fishing because:
1. Caught fish don’t die
a natural death;
F
2. A fished population is
a younger population,
with a lower death rate;
3. Individuals in a fished
population have access to
more resources, so
they are healthier and
have a lower death rate.
Percentage contribution of year classes of Norwegian spring spawn
herring to the adult stock from 1954 through 1962. The very good
year class of 1950 began first appearing in significant numbers in
1954 and dominated the adult stock throughout this period.
The Canadian Cod Example:
Fished to Commercial Extinction Before
Establishment of a Moratorium: No Recovery
of the Stock, No Recovery of the Fishery
Social
Concerns
Information
Quality
Natural
Variability
Characteristics of r-selected and K-selected populations
parameter
r-selected
K-selected
Environment
variable and/or
unpredictable
constant and/or
predictable
Lifespan
short
long
Growth rate
fast
slow
Fecundity
high
low
Natural mortality
high
low
Population dynamics
unstable
stable
HOW MANY FISH SHOULD WE CATCH?
SUBSTANTIALLY LESS THAN THE
MAXIMUM SUSTAINABLE YIELD
THAT IS CALCULATED
Clupeid & Gadoid Fisheries
r – Selected Species
~1/3 Global Fisheries
Instability  Management Challenges
Commercial catch of Japanese pilchards
Migration
routes of the
Norwegian
springspawning
herring during
the period
1963-1966.
The location of the
nine major
populations of
British
Columbia
herring.
Commercial catches of cod in the North Sea
(A) Catch of North Sea Herring and (B) spawning stock biomass of the autumn
spawning herring. The dashed line in panel B is the target spawning stock of 1.3 Mt
recommended by the ICES.
Harvest of
sexually
immature
fish
Over
Habitat
Recruitm’t Closure of
Capitlizat’n destruction overfishing fishery
Japanese
Pilchards
Norwegian
springspawning
Herring
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Canadian
Pacific
Herring
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Canadian
Atlantic Cod
N. Sea Cod
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N. Sea
Herring
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Peruvian Anchoveta Fishery
I. The Physical Setting
II. The Upwelling Ecosystem
III. Anchoveta Ecology
IV.History of the Anchoveta Fishery
Surface current system
off the coast of Peru.
Dashed line marks the
approximate boundary
between the Peru
coastal current and the
Peru oceanic current
(Humboldt Current). The
shaded area is the
approximate area of the
coastal current system
occupied by the
Peruvian anchovy
stocks.
The Upwelling Ecosystem
I.
Nutrient-rich waters from beneath the nutricline fertilize the
euphotic zone with nitrate and phosphate
II. High nitrate and phosphate enables high primary productivity
by phytoplankton
II. Anchoveta graze this nutritional resource
III. Anchoveta are then eaten by mackerel (from below) and
guano birds (from above)
Anchoveta Ecology
I. Population is confined to the Peru Coastal Current system
II. Feed low on the food chain
III. 4-year lifespan
IV. Spawning year-round, with peaks in Sept-Oct and Feb-Mar
V. Recruited to the fishery at 5 months of age
Anchoveta Ecology
V. Recruited to the fishery at 5 months of age
VI. Sexual maturity at 12 months of age
VII. Very high fecundity:
15,000 eggs/spawn, 24 spawns/year
VIII. Very high mortality prior to recruitment: > 99%
IX. After recruitment, mortality is ~ 16%
X. A modest drop in population size enhances recruitment
History of the Anchoveta Fishery
BACKGROUND
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Artisanal fishing prevails from pre-colonial times to ~1900
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Guano mining becomes Peru’s major export industry
during the 1800s into the 1900s
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Compania Administradora de Guano stifles attempts to
expand and industrialize fishing in 1910s and 1920s
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First fish processing plant built in the 1930s
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As guano supplies are depleted, CAdG shows a slight
interest in fishmeal
History of the Anchoveta Fishery
Development
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1950 - The collapse of the California sardine fishery
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Increasing demand for fish meal as feed components
for the growing US livestock industry
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Transfer of reduction fisheries infrastructure from
California to Peru
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Both the government and commercial banks support
the development of the Anchoveta reduction fishery
History of the Anchoveta Fishery
Development
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1950s - Number of fishmeal plants grows to 49
- Fishmeal production grows from <1,000
metric tons to 117,000 metric tons
- Fishmeal value grows from $100,000
to $11,300,000
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1960s - Number of fishmeal plants grows to 154
- Fishmeal production grows to 1,622,000
metric tons
- Fishmeal value grows to $183,200,000
Catch of
anchoveta has
been highly
variable. In the
decade between
1962 and 1971,
annual yields
averaged 9.7 Mt,
but the catch
dropped
dramatically in
1972 and
averaged only 1.3
Mt in the decade
between 1976 and
1985.
Effects of El Niño on Anchoveta Catch
Impact of El Niño on Peruvian anchovies
Possible impacts:
anchovies starve
poor recruitment
changes in predation
Response of anchovies
concentrate in cold water nearer the coastline
move into deeper water and disperse
Ecological Summary
Advantages:
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An Extraordinary Combination of Nutritional Resources
and an r-Selected Fish
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Short Food Chain
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“Simple” Sources of Mortality
Problems:
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Complex Biological-Meteorological Interactions
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Variable Recruitment
Management Summary
Advantages:
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An Extraordinary Combination of Nutritional Resources
and an r-Selected Fish
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Fishery within the Peruvian EEZ
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National and International Fisheries Scientists Involved
Problems:
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Complex Biological-Meteorological Interactions
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Harvesting Prior to Sexual Maturity
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Overcapitalization and Socio-Political Pressures
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MSY as a target
TUNA TALES
TUNA I
The World’s Tuna Fisheries
TUNA II
A Fishery Management Case Study:
Yellowfin Tuna and Dolphins
in the Eastern Tropical Pacific
TUNA III
The Mighty Bluefin
Table 7.1. Principal species of tuna involved in commercial fishing
Common name
Scientific name
Albacore
Thunnus alalunga
Bigeye
Thunnus obesus
Skipjack
Katsuwonus pelamis
Yellowfin
Thunnus aobacares
Atlantic bluefin
Thunnus thynnus
Pacific bluefin
Thunnus orientalis
Southern bluefin
Thunnus maccoyii
Some things to think about
Tuna enjoy:
The eastern sides of ocean basins have:
Warm Water
Shallow Thermocline
Lots of Oxygen
Shallow Oxygen Zone
Lots of Food
Nutrient-Rich Upwelling Zones
Along the west coasts of continents tuna can be found:
In Higher Concentrations
In Shallower Water
Closer to Shore
For Easier Fishing
Pertinent information on commercially important tuna species
Species
Length
(cm)
Weight
(kg)
Age of sexual
maturity
(years)
Lifespan
(years)
Albacore
60-90
10-20
5
10
Bigeye
80-180
15-20
4
10
Skipjack
30-80
8-10
2
12
Yellowfin
40-180
5-20
3
10
Atlantic
bluefin
45-450
135-680
4-8
15-30
Pacific
bluefin
150-300
300-555
6
30
200
200
8-12
40
Southern
bluefin
Commercial catches of skipjack, yellowfin, bigeye, and albacore tuna
Skipjack information
Most catch occurs in the Pacific (70%) and Indian
(24%) oceans.
Smallest of the commercially important tunas
Tendency to school
Most skipjack are caught with purse seines.
Diet includes clupeids, crustaceans, and mollusks
Major market for skipjack tuna is canned tuna
Principal nations contributing to the Catch of Tuna
• Various tunas
• Various fishing areas
Yellowfin information
Geographical distribution and spawning behavior
similar to skipjack.
Tend to associate with dolphins more than any
other species.
Pacific (67%) and Indian Ocean (22%) account for
most of the catch.
Much of the fishing is done with purse seines.
Canned tuna (light tuna) is again the primary
market.
Bigeye information
Similar to yellowfin… greater depths… higher fat content.
Catch distribution: Pacific (50%), Indian (30%), Atlantic (20%).
Small bigeye are caught as bycatch of purse seining for skipjack
and yellowfin. The larger and more valuable bigeye are taken with
long lines.
Less suited for canning than skipjack, yellowfin, or albacore tuna.
Most popular as fresh fillets (sashimi) and fresh whole fish.
Principal market is Japan
Principal fishing nations are Japan and Taiwan.
Little known about the ecology of bigeye tuna
Not sure if stocks are being fully exploited. The
Bycatch of sexually immature bigeye is a concern
Albacore information
Temperate water fish, and stocks in the N and S
hemisphere are disjoint.
The principal fishing areas are the western and central
Pacific
Caught with pole-and-line, surface trolling, or long
lines, no purse seine
The principal market for albacore is canned tuna…
“white tuna”.
Japan and Taiwan dominate the catch.
Atlantic Bluefin information
Atlantic Bluefin found only in the N. Atlantic, Mediterranean, Black
Sea. Bluefin in the South Atlantic are S. Bluefin.
Atlantic bluefin are the largest of the tunas
Two spawning areas: Gulf of Mexico and Mediterranean Sea
Controversy over whether the stocks should be considered
separately
these tuna definitely make trans-Atlantic
migrations.
<1970 ~$0.10/kg….Now$20-70/kg
Increasing demand to supply the Japanese sushi and sashimi
markets
development of air freight in the early 1970s
Management: International Commission for the Conservation of
Atlantic Tunas (ICCAT) formed in 1969.
Pacific Bluefin information
The only unregulated Bluefin fishery in the
world.
Japan accounts ~64% of catch, most from NW
Pacific.
Unlike the Atlantic Bluefin…only one stock of
Pacific Bluefin tuna.
Caught on a variety of gear…bycatch….often
juveniles
Almost all taken in the eastern Pacific are
sexually immature
Southern Bluefin information
The most overexploited of the Bluefin tuna.
Only one known breeding ground (Indian Ocean) The fishery is
dominated by Japan and Australia.
As with other Bluefins, surface gear takes sexually immature fish.
Since1980… victim of recruitment overfishing
Commission for the Conservation of Southern Bluefin Tuna (CCSBT)
set catch quotas...no evidence that the spawning stock is recovering
…further reductions in the catch quotas will be needed to give the
stock a chance to recover.
The long time to reach sexual maturity makes this species particularly
vulnerable to overfishing.
Management:
IATTC and CYRA
Inter-American Tropical Tuna
Commission (IATTC). Formed
in 1950 by USA and Costa
Rica. Now includes 12
countries.
Purview is eastern tropical
Pacific to 140o west longitude.
Management has been almost
entirely concerned with
yellowfin tuna.
Commission’s Yellowfin
Regulatory Area (CYRA) is de
facto where the ITTAC is
regulating tuna catches
Background on the tuna/dolphin problem
Problem is confined to the eastern tropical Pacific, where
yellowfin tuna congregate under schools of certain species of
dolphins
For many years fishing was done by chumming (pole and line)
with no impact on dolphins
Purse seining phased in during last few years of 1950s
Combination of fishing tuna located under schools of dolphins
proved
deadly to dolphins and damaging to tuna stocks
Tuna can be found by several methods. “Porpoise” sets actually
account for less than half the purse seine sets during the 1970s.
Key strategies for releasing dolphins: backing down and Medina
panels
Marine Mammal Protection Act – 1972
NMFS Implementation of MMPA with respect to
dolphin stocks
Early 1980s – U.S. wants to put observers on all tuna boats. Observers
on fewer than 50% of U.S. boats and only a handful of foreign boat-trips.
Early 1980s – U.S. wants to ban sundown sets
Tuna boats start to drop out of U.S. fleet
Late 1980s – dolphin kills start to increase
Dolphin-safe tuna
1990 – Dolphin Protection Consumer Information Act establishes
standards for “dolphin-safe”
April 12, 1990 – Star-Kist, Bumble Bee, and Chicken of the Sea
announce that they will not buy tuna caught using porpoise sets
1991 – U.S. embargoes challenged by Mexico – General Agreement
on Tariffs and Trade (GATT)
Reported dolphin mortalities continue to drop. Kill has been less
than 2,000 animals per year since 1998
Lessons Learned?
Pluses
Consumers, via their government, pushed effectively for the
implementation of management
Benefits to the fishery from accepting the management plan
1. Main markets didn’t want to buy dead dolphin
2. Spared dolphins live to help find tuna again
Minuses
Expenses to the industry have forced much of the fishing
fleet to jurisdictions where the management plan can
be evaded
ATLANTIC BLUEFIN
THUNNUS THYNNUS
Early History:
Caught in Mediterranean coastal
fisheries, using artisanal techniques Π
(Hand lines, and coastal traps, nets and
pounds)
A little more recently:
~1900 to ~1960.
Sport fishing, off the Atlantic coasts
of Canada and the U.S.
A Nova Scotia tournament recorded a
peak landingof 1,760 fish in 1949.
Fish caught in tournaments were sold
to pet food companies for pennies a
pound.
And then starting in the 1960s and
1970s:
Japanese demand for high-fat tuna;
The availability of airfreighting from
the Atlantic to Japan;
Made recreationally-caught Atlantic
Bluefin worth many dollars a pound.
Bluefin tuna being readied for auction at Tokyo’s Tsukiji Fish Market.
The Current Situation:
Vast Over-Capitalization in European
and African fisheries.
In 2008, catch potential of E&A
fisheries - > 54,000 tonnes.
In 2008, ICCAT catch limits of E&A
fisheries Π28,500 tonnes.
In 2008, fisheries scientists
recommended catch - 15,000 tonnes.
Science, 1995-2005:
Western Stock fish cross the Atlantic,
and vice-versa
The poorly managed and poorly
regulated European and African
fisheries are wiping out the Western
Stock.
Nature, 2005
The Economist, 2009
Whales and Whaling
I. Whales are Really, Really K-selected
II. History of Whaling
III. Management of Whaling
IV. Molecular Biology as a Management Tool
V. Effects of Industrial Whaling on Oceanic
Ecosystems
Whales are Extremely K-selected.
The Humpback Whale as an Example
Virgin Stock:
115,000
Life Span:
80-90 yrs
Sexual Maturity:
4-7 yrs
Reproduction:
1 calf per female, every 2-3 years
Harvest:
5,000/ yr from 1935 to 1965
Rate of Decrease:
From 4% (1935) to 25% (1965) of the
stock: 150,000 in aggregate!
Stock in 1965:
20,000
Current Stock:
35,000
Rate of Increase:
~1.5% per year
Why were pre-whaling populations so low? (Bienfang, 2005)
Perhaps they weren’t (Roman & Palumbi, 2003)
Virgin Stock:
724,000
Stock in 1965:
20,000
Current Stock:
35,000
Rate of Increase:
~1.5% per year
IWC:
“Catches should not be allowed on stocks
below 54% of the carrying capacity”
Conclusion:
It will be many, many decades before it
will be wise to harvest Humpbacks.
Like the blue and fin whales,
humpbacks are found in all
the ocean basins to the edges
of polar ice. Unlike the blue
and fin whales, humpbacks
migrate into tropical waters
during the mating season, and
they have a distinct
preference for shallow waters
when not migrating. The latter
characteristic has made them
vulnerable to whaling.
Humpback and fin whales
attracted the attention of the
modern whaling industry at
about the same time, i.e., after
the blue whale stocks had
been seriously depleted.
Bowheads have longest
baleen plates of any whale
– 4.5 meters
Confined to northern
hemisphere and remain
above 60oN at all times
Hunted by Eskimos for
thousands of years
Northern and Southern Right
whales similar to bowheads, but
smaller.
Hunting of Right whales began
as early as the 10th century, and
during the 19th century roughly
100,000 Right whales were
killed by the whaling industry.
Right whales were seriously impacted by early years of whaling. All right
whales have been on protected status since 1935.
Current stock estimates:
bowheads: 8,000 – 12,000
northern right: 500 – 1,000
southern right: 3,000
Table 10.2. Some characteristics of Right Whales.
Species
Age of sexual maturity
(years)
Lifespan (years)
Northern Right (Black Right)
5-10
70
Southern Right
5-10
70
6
100
Bowhead (Greenland Right)
Right whales
Characteristics of interest to whalers and OCE331/MARE360
Students
Slow
Unaggressive
Float when Killed
Rich in Blubber
Characteristics of interest to evolutionary biologists and players
of Trivial Pursuit
Sperm Competition
Largest Gonads on the Planet (1,100 lbs per testis)
Long Penis (10’)
Large Ejaculate (5 gallons)
The modern era of whaling
`
Technological developments:
Harpoon gun with explosive head – 1864
Steam powered catcher ships – about the same time
Pelagic factory ships – 1903
Inflating carcass with compressed air – around the same time
Stern ramps on factory ships – 1925
From Whitehead, 2002
IWC quotas and catches of whales in the Southern Ocean from the 1945/46
whaling season through the 1971/72 season.
A General Case Study: Whale Meat in the Supermarket
1. Demonstration of protected species being killed, processed, and sold.
2. Demonstration of illegal transfer of protected species
across national boundaries.
3. Demonstration of false advertising.
Baker, C.S., and Palumbi, S.R. (1994) Which Whales are Hunted?
A Molecular Genetic Approach to Monitoring Whaling.
Science 266:1538-1539.
Palumbi Strategy
1. Assemble a “Lab in a Suitcase”
Thermocycler; PCR Primers; DNA Polymerase;
Pipettors; Microfuge Tubes; Buffers
2. Fly to Japan
3. Check in to a hotel
3. Go shopping
4. Extract and amplify DNA from commercially
available whale meat
3. Discard the whale meat
(it’s illegal to move it from country to country)
6. Take the amplified DNA home for sequencing and analysis
Identities of Commercial Whale Products in Japanese Markets
Species
1993
1995
1996
N. minke whale
S. minke whale
3
22
4
37
9
46
Bryde’s whale
1
1
0
Humpback whale
1
0
0
Fin whale
Blue whale
7
1
3
1
2
0
Dolphi ns
5
5
18
Effects of Industrial Whaling on Oceanic
Ecosystems
I. Bottom-Up Effects
II. Top-Down Effects
A
B
C
D
E
Grey Whale Carcass, 6 weeks on the bottom, 1675 metres
Mobile Scavenger Stage
Pre-whaling: Carcasses on beaches and migration routes
Open-Boat Whaling: Wider distribution of carcasses, and
probably an increase in the number of whale falls
Industrial Whaling: An estimated 10-fold reduction in whale falls
From Springer et al., 2003
Tragedy of Freedom in a Commons
Pasture Example (the village green)
What are the benefits and costs to me of
adding one more animal to my herd?
Benefit: I get all the biomass generated by
that animal
Costs: The village green is degraded a bit,
but that cost is shared by all other
animal owners
Conscience is Self-Eliminating
and Pathogenic
The genes of those with the conscience to
restrict their uses of the Commons or to
restrict their breeding will sooner
(themselves) or later (their lack of offspring)
be eliminated from the population.
Mutual Coercion
Mutually Agreed Upon
We institute … taxes and other coercive devices to
escape the horror of the Commons
The Ingredients for Avoiding a
Tragedy of the Commons:
Elinor Ostrom
1. The nature of the resource
2. Recognition of resource depletion
3. Nature of the community:
“Small and stable populations
with a thick social network and social
norms promoting conservation do better”
The Bermuda Fisheries:
A Tragedy of the Commons Averted?
Background:
1. A Problem Perceived
2. A Study Undertaken
3. A Policy Changed
Prior to 1970:
Resource was in excess of the demand.
A “Commons” use of the resource seemed OK.
Policy was to increase fisheries activity.
In 1975:
Policy was to “exploit the harvestable resources
to their maximum sustainable levels
1980 and 1984 attempts to regulate the use of fish pots,
but problems remained:
Pots were too indiscriminately efficient
Pot fishery was too difficult to police
Fishermen used more pots than they were allotted and tagged their illegal pots with other fisher’s names!
Fishermen took other fisher’s pots
1980s: A growth in the use of the resource by other
economic interests.
Tourism: Scuba, Snorkel, Glass-Bottom Boat
Charter fishermen found their interests aligned
more with tourism than with commercial
fishing
1990:Anne Cartwright DeCouto moves the Fish Pot
Ban through Parliament
Fish Pots redeemed by the government for
substantial cash compensation
1991 and beyond:
Fish Pot ban to be permanent
Reef fishery goal to be “obtaining the maximum
yield of fish consistent with the conservation
of resources for other users."
In short, “Fish to well below the MSY”
The Bermuda Example of Averting a
“Tragedy of the Commons”
Made possible by a fortuitous set of circumstances:
A. Affluence
B. Isolation
C. Changing Economic Interests
D. An Advantageous Political Environment