Hugo Grotius Mare Liberum 1609 Whales Norwegian herring Japanese sardine Peruvian anchovy Can. N....

Hugo GrotiusMare Liberum

1609• Whales• Norwegian herring• Japanese sardine• Peruvian anchovy• Can. N. Atlantic cod

• Technology• Capital Investment• Fisheries Information• Politics• Social Issues• Tragedy of commons• Population

Total Global Fisheries Harvest ~160Mt

• Year CAP AQ• 2002 94.5 52• 2003 91.8 55.2• 2004 96 60• 2005 95.5 63.3• 2006 93.1 66.7

• Capture Fisheries are constant at ~90-95Mt

• Aquaculture is steadily increasing

Table 1.1 Disposition of the total aquatic catch for 2002

Use % of total catch 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 (w3’s, w6’s)

How the Oceans Make Fish

• Primary Production Commercial Fish

• 3 Types of Ocean Areas– Open Ocean– Coastal Areas– Upwelling Areas

Permanent pycnocline

Sea surface

sinking

Excretion, death, and sinking

grazing

Upwelling and turbulent diffusion

regeneration

phytoplankton

herbivores

carnivores

Winter mixed layer

dissolved nutrients

Nutrients in detritus

dissolved nutrients

grazing

Table 1.5 Estimates of marine primary production from Martin et al. (1987)

Province % of ocean

Area(1012 m2)

Mean production (gC m-2 y-1)

Global production(Pg C y-1)

% of primary

production

Open ocean

90.0 326 130 42.38 82

Coastal zone

9.9 36 250 9.00 18

upwelling 0.1 0.36 420 0.15 0.4

total 100 362 142 51.53 100

Open Ocean Area

• Deep• Low inputs• Mostly Regen. Nutrs.• Stable Temporally• Nutrient Limited

• Small Phytoplankton

• Long Food Chains

• Low Comm.Fish Yield– Big area– High value Needed

113 226

Algal picoplankton and nanoplankton (42,380)

Flagellates (8,476)

Ciliates (1,695)

Crustacean zooplankton (339)

Mesopelagic vertical migrators (45.2)Chaetognaths, micronekton (22.6)

Small tuna, salmon, squid (3.39)

Large tuna, sharks, billfish (0.51)

Trophic level

1

2

3

4

5

6

7

Coastal Areas

• Shallow• Seasonal Inputs• Seasonal Variability• ~50% New Nutrients• Spring bloom (40%)

• Larger Phytoplankton

• Shorter Food Chains– Clupeids

• Benthic Food Chains– Gadoid fishes– Mollusks– Crustaceans

• High Comm. Fish Yield

2816.316.3

102306

29

20

97

225408

1,800

6,000

1,200

phytoplankton (9,000)

flagellates (1,200)

ciliates (240)

crustacean zooplankton (408)

invertebrate carnivores (61)

bacteria (322) meiobenthos (19)

macrobenthos (49) epifauna (4)

pelagic fish (32.6) demersal fish (10)

large demersal fish (0.4)

natural mortalityand fishing

Upwelling Areas

• Shallow• Seasonal Inputs• Seasonally Steady• Mostly New Nutrients

• Larger Phytoplankton

• Short Food Chains

• Clupeid fish

• High Comm. Fish Yield

2.36.8

64.5

42.75

phytoplankton (150)

flagellates (12.9)

ciliates (2.6)crustacean zooplankton

(9.1)

invertebrate carnivores (1.4) pelagic fish (9.3)

natural mortality and fishing

42.75

Sustainable Catch

• SFC = Grs.Pop.Growth – Nat.Mortality

• w/o a Fishery (i.e.F=0), GPG balances NM– otherwise fish vanish, i.e. NM>GPG or– fish take over the planet, i.e. GPG>NM– In virgin fishery GPG ~NM– In early fishery FC+NM ~ GPG– As Pop declines GPG >NM

• more resources, younger stocks, etc.

Maximum Sustainable Yield

• MSY relative to virgin population

• ~25%; surely <50%

• MSY is a TERM, not a TARGET

• Why? Perturbations; bad info; unknowns

• Calc MSY ~140Mt > Catch ~90Mt

D=$10,000, I=10%/y, Ic=constant, W=$0, Wc=constant

Y YEBbW W YEBaW0 $11,000 0 $11,000

1 $12,100 0 $12,100

2 $13,310 0 $13,310

3 $14,641 0 $14,641

4 $16,105 0 $16,105

5 $17,716 0 $17,716

6 $19,487 0 $19,487

7 $21,436 0 $21,436

8 $23,579 0 $23,579

9 $25,937 0 $25,937

10 $28,531 0 $28,531

D=$10,000, I=10%/y, Ic=constant, W=$1000, Wc=constant

Y YEBbW W YEBaW0 $11,000 1000 $10,000

1 $11,000 1000 $10,000

2 $11,000 1000 $10,000

3 $11,000 1000 $10,000

4 $11,000 1000 $10,000

5 $11,000 1000 $10,000

6 $11,000 1000 $10,000

7 $11,000 1000 $10,000

8 $11,000 1000 $10,000

9 $11,000 1000 $10,000

10 $11,000 1000 $10,000

D=$10,000, I=10%/y, Ic=constant, W=$1000, Wc=fluctuating

Y YEBbW W YEBaW0 $11,000 1000 $10,000

1 $11,000 2000 $9,000

1 $9,900 1000 $8,900

2 $9,790 500 $9,200

3 $10,219 1000 $9,219

4 $10,141 500 $9,641

5 $10,605 2000 $8,605

6 $9,465 1000 $8,465

7 $9,312 1000 $8,312

8 $9,143 500 $8,643

9 $9,508 500 $9,008

D=$10,000, I=10%/y, Ic=fluctuating, W=$1000, Wc=constant

Y YEBbW W YEBaW0 $10,500 1000 $9,500

1 $10,450 1000 $9,450

2 $9,639 1000 $8,639

3 $9,503 1000 $8,503

4 $9,353 1000 $8,353

5 $8,938 1000 $7,938

6 $8,732 1000 $7,732

7 $8,505 1000 $7,505

8 $8,631 1000 $7,631

9 $8,241 1000 $7,241

10 $8,182 1000 $7,182

Unconventional Fisheries

• Antarctic Krill– NM~400Mt/y; MSY >> 60Mt/y– Variable biomass, distant, shelf life, taste– Krill butter, cheese, sausage, (not high-value)

• Midwater fish– myctophids, lanternfish, MSY >>110 Mt/y

• Squid– C~3Mt/y; whales~100Mt/y; MSY~25Mt/y

Characteristics of Deep-Sea Habitats

benthopelagic

Why care? - The Deep-Sea is HUGE!

• ~70% of the earths surface is covered by the oceans

• ~90% of this area is water with depths greater than 200 meters

• The deep-sea is the single largest living place on the planet

Deep-sea fisheries are expanding

orange roughy

rattails (grenadiers)

patagonian toothfish

(chilean seabass)

Counter illumination – the use of bioluminescence to eliminate the ventral shadow