Sustainability

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					                    The Blue Revolution
 Over 220 species of finfish & shellfish are farmed.
 Almost 31,000,000 mt of the world’s total wild fisheries
  production is used for animal feed each year; 15% of which is used
  in fish feed.
 Aquacultured fish are an
  inexpensive source of highly
  nutritious animal protein, have
  become an important factor for
  improving food security, raising
  nutritional standards, &
  alleviating poverty, especially in
  the poorest countries.
World Capture & Aquaculture Production   (with China)
    Freshwater & Marine Aquaculture Production by State (1998)
   Significant regional variation.
   States in the Mississippi Delta represent bulk of production (catfish).
   Washington State ($30md) & Maine ($64.1md) are major salmon farming states.
   Value is total aquaculture sales in millions of dollars.
U.S. Aquaculture Production by Species & Growth Since 1989
                            Sustainability

“Sustainable development is the management & conservation of
  the natural resource base & the orientation of technological &
  instructional change in such a manner as to ensure the
  attainment & continued satisfaction of human needs for
  present & future generations. Such sustainable development
  conserves land, water, plant, and animal genetic resources, is
  environmentally non-degrading, technically appropriate,
  economically viable, and socially acceptable.”

           [FAO (1991): Reducing environmental impacts of coastal aquaculture.]
             Fish Meal & Fish Oil in Fish Feed
 Fish meal & fish oil requirements:
     Many intensive & semi-intensive aquaculture systems use 2-5 times more fish protein
     to feed the farmed fish than is supplied by the farmed product.
    For the most commonly farmed fish, 1.9 kg of wild fish is required for every 1.0 kg of
     farm-raised fish (only true for salmon & shrimp).
    In total, aquaculture is a net producer, generating 3.5-4.0 kg of food fish for each kg
     of pelagic fish used in fishmeal.
    Poultry & swine industry is the largest consumer of fishmeal; proportionally, fishmeal
     is higher in aquaculture feed.
 Herbivores & omnivores:
    Carp (80%) and tilapia (65%) are farmed without the use of modern compound feeds.
    Generally, catfish farms use protein meal from soybeans, cottonseed, and peanuts.
 Carnivorous fish & marine shrimp:
    Dominant form of protein in diet from fishmeal.
    Dietary essential amino acids & fatty acids (EPA & DHA) are not found in vegetable
     oils.
Flow Chart of Capture
  & Farmed Fisheries
Products from Aquatic
  Primary Production
(units are mmt of fish)
              Predicted Growth in Aquaculture Production of Species fed Compound Feeds
                                                                                Volume of
                                              Volume of        Percent of
                    Annual rate of growth                                      Production               FCR                Total feed
                                              production      Production
                        2000-2010                                              on fish feed    (dry feed to wet fish)      in 000 mt
                                               in 000 mt      on fish feed
                                                                                in 000 mt
                                            2000     2010     2000    2010   2000      2010      2000         2010       2000      2010


Salmon                       7%              876     1,723    100%   100%    876       1,723      1.4          1.1       1,226     1,896


Marine fish                  5%              856     1,394    60%     80%    514       1,115      2.2          2.0       1,130     2,231


Other marine fish           20%              105      650     100%   100%    105        650       2.2          2.0       231       1,300


Shrimp                       5%             1,034    1,684    80%     90%    827       1,516      1.8          1.6       1,489     2,425


Eel                          2%              216      263     80%     90%    173        237       2.0          1.2       346        284


Milkfish                     2%              379      462     40%     75%    152        347       2.0          1.6       303        554


Trout                        5%              450      733     100%   100%    450        733       1.4          1.1       630        806


Tilapia                      7%              974     1,916    40%     60%    390       1,150      2.0          1.5       779       1,724


Catfish                      5%              371      604     85%     90%    315        544       1.6          1.4       505        761


Carp                         7%             13,983   27,507   25%     50%    3,496    13,754      2.0          1.5       6,992    20,630


Total                                       19,244   36,936                  7,297    21,767                            13,6631   32,611
Relationship Between Aquaculture Production, Pelagic
   Fish Landings & Fishmeal Production: 1984-2000




  Fishmeal production has changed very little over the past 15 years.
  Fishmeal use has been reallocated with aquaculture’s use increasing from
  10% in 1988 to 35% in 1998. But this may represent an environmentally
  friendly use since fish are more efficient feed converters than terrestrial
  livestock.
Net Loss from
Ocean to Plate
           Predicted Growth in Wild Fish Used in Fishmeal & Fish oil for Aquaculture
                    Thousands of tons of wild     Ratio of wild fish used for    Thousands of tons of         Ratio of wild fish used for
                      fish used for fishmeal    fishmeal to final production    wild fish used for fish oil   fish oil to final production
                                                   of fish fed on fishmeal                                        of fish fed in fish oil
                      2000          2010           2000             2010          2000           2010           2000            2010

Salmon                2,308         2,674           2.6              1.6         2,548           3,146           2.9             1.8

Marine fish           2,388         4,192           4.6              3.8         1,876           2,781           3.7             2.5

Other marine fish      597          2,750           5.7              4.2          191            1,295           1.8             2.0

Shrimp                1,748         2,280           2.1              1.5          249             606            0.3             0.4

Eel                    813           536            4.7              2.3          141             191            0.8             0.8

Milkfish               169           132            1.1              0.4           50             91             0.3             0.3

Trout                  888           949            2.0              1.3          789            1,004           1.8             1.4

Tilapia                259           282            0.7              0.2           66             75             0.2             0.1

Catfish                71             -             0.2               -            42              -             0.1             0.0

Carp                  1,645         2,425           0.5              0.2            -             855            0.0             0.1

Total                10,885        16,220           1.5              0.7         5,951          10,043           0.8             0.5
                         Environmental Issues
 Ecological impacts:
     Enrichment & changes in biodiversity.
           Release of soluble inorganic nutrients.
       Interaction with food web.
          Competition between planktonic herbivores (bivalves).

       Oxygen consumption
          Direct from high density farming.

          Indirect from organic waste decomposition.

       Disturbance of wildlife & habitat modification/destruction.
          Increases in some bird populations (cormorants, herons, kingfishers, pelicans) beyond
            their normal carrying capacity.
          Mangrove habitat loss.

       Interaction between escaped farmed stock & wild species.
          Domesticated farmed fish interbreed with wild fish.

       Introductions & transfers.
          Non-native (exotic) species (from fish to disease)

       Bioactive compounds
          Pesticides, antibiotics & hormones
                 Aquaculture Waste

 Untreated wastewater containing uneaten feed and fish feces
  contribute to pollution near coastal ponds & cages (25-33% of
  feed consumed by fish is ejected as feces).
 Nitrogen wastes exceed assimilative capacity of receiving
  waters can lead to deterioration in water quality.
    Approximately 3-10 kg of phosphorus and 39-55 kg of
     nitrogen are released to the environment for every metric
     to of fish produced.
 Waste Stream: Pollution from Farming Fish
 in Net Pens
• Estimated that a typical
  salmon farm produces as
  much waste (fecal solids)
  as 65,505 people.
• Decomposition can result
  in hypoxia in sediments.
• Lotic system recover
  more quickly than lentic
  systems.
Water Column Dissolved Inorganic Nitrogen in the Vicinity of
  Salmon Farms, Puget Sound, Washington State (1995)

                         Dissolved Inorganic Nitrogen (um/L)
    Year (Farm)   100’ upstream   20’ downstream   100’ downstream
    1995 (A)          9.58            14.87             11.43
    1994 (B)         21.34            22.87             23.04
    1989 (C)         22.51            25.83             23.87
    1994 (D)         12.54            11.80             12.15
    1995 (E)          5.47             5.16              5.18
    1995 (F)         10.70            10.83             11.85
    1995 (G)          6.06             6.21              5.71
    1994 (H)          9.78            11.34             10.80
         Habitat Modification/Destruction
 Mangroves & coastal wetlands         Eutrophication
  transformed into milkfish &          Water diversion
  shrimp ponds (SE Asia).
    Mangroves serve as nurseries
      to juvenile fish & shellfish.
    In coastal regions of Thailand
      65,000 ha of mangroves have
      been converted to shrimp
      ponds (<10%).
    Most of the loss is due to
      clearing for rice production,
      grazing, urban development,
      fuel, construction materials,
      wood pulp & tourism.
               Chemicals & Antibiotics

 Antibiotic resistance for water-borne pathogens.
 Antibiotics in feed can reduce microbial degradation of
  uneaten feed and feces.
 Antibiotics can build up in tissue of farmed fish and persist.
    Oxytertacycline, oxolinic acid, trimethoprim, sulphadiazine,
     & amoxycillin.
 Metals in fish feed and cleansers can enter ecosystem.
    Copper, zinc, cadmium, & mercury.
 A shift to organic standards.
Some Chemicals Used in Aquaculture & Potential
       Environmental & Health Effects
                             Escape
 Escapes of cultured fish occur because of:
    Storm damage
    Collisions
    Predator attacks
    Vandalism
    Accidental loss associated with
     handling.
 Escapes estimated at 3 – 5% from cage
  production.
Number of Fish Escaping from Washington State &
          British Columbia Fish Farms
         Year     Washington State1 British Columbia2
         1996            107,000          53,104
         1997            369,000          56,891
         1998             22,639          91,168
         1999             115,000         35,730
         2000                0           68,947
         2001                0           57,968
         2002                0            18,380
         2003                0             ND
         2004             24,552         39,400
         2005             2,500            ND
         1: Atlantic salmon
         2: Atlantic & Chinook salmon
Farmed Salmon: Quantity by Country
                            Social Issues
 Scio-economic impacts:
    Large-scale mangrove conversion for shrimp & fish farming in Ecuador
       have displaced rural communities that depended on the mangrove
       resources for their livelihood.
      Economic impact of disease outbreak in Taiwanese shrimp industry.
      Land subsidence (sinking) & salinization of groundwater in Taiwan from
       shrimp & eel culture.
      Financial losses to Norwegian cage-farming industry from Hitra disease
       outbreaks.
      Public health issues from red-tide outbreaks where shellfish culture
       occurs.
      Resource ownership is often ambiguous.
World’s 20 Largest Salmon Farming Companies
                           Conservation

 Displacement of wild populations.
    Escaped farmed fish can reduce the viability of wild populations
     especially those with small populations due to overfishing, habitat loss
     or other causes.
 Genetic impact.
    Escaped farmed fish may breed with wild fish, thereby introducing
     domesticated genes & reducing adaptations to the natural
     environment.
 Transgenic fish (GMO).
    Escaped farmed fish may breed with wild fish and spread the
     transgene.
 Parasites & disease.
    Transfer to wild fish & appearance of rare, but deadly, diseases in
     densely cultured farmed fish.
     Enhancement & Supplement Stocking

 Hatcheries raising Pacific salmon & steelhead trout release >5 billion
  juvenile fish into the North Pacific every year.
 Sharp declines in reproductive success of wild broodstock occurs after a
  short time in captivity.
     37.5% fitness decline per captive-reared generation.
 Unintentional domestication selection & relaxation of natural selection,
  due to artificially modified & well-protected rearing environments for
  hatchery fish, may be occurring.
 To prevent domestication & fitness decline repeat use of captive-reared
  fish for reproduction should be avoided.
    But repeat capture of wild fish for broodstock is strongly criticized.
Some Genetically Modified Organisms
   Tested for Use in Aquaculture
Estimated 2000 Fish-meal & Fish-oil Use
         in World Aquaculture
                Strategies for the Future
 Formulate aquaculture development & management plans.
 Apply environmental impact assessment to aquaculture
    developments.
   Select suitable sites & monitor ecological change.
   Apply best management practices (BMP) to aquaculture
    operations.
   Establish guidelines for governing use of natural resources.
   Establish guidelines for use of bioactive compounds.
   Assess & evaluate the consequences of using transfers &
    exotic species.
   Regulate effluent discharge.
       Ecological Link Between Intensive Fish & Shrimp
               Aquaculture & Capture Fisheries
(Blue line = main flows from aquatic production base through fisheries & aquaculture to human consumption of
              seafood; Red lines = negative feedback; Values = mmt of fish, shellfish & seaweeds).
              Sustainable Aquaculture
 Farm down the food web.
    More herbivores & omnivores;
 Lower demand for fishmeal & fish oil.
    More research into oilseeds, meat byproducts, & microbial
     proteins.
 Integrate production systems; polyculture.
 More recirculating production systems; especially in urban
  areas.
 More inland farm operations.
    Effluent can be treated more effectively inland than in
     coastal regions.
Traditional
Integrated
Aquaculture: Using
Practices from the
Past for a
Sustainable Future



Traditional rice-fish system
can provide mutual benefits
to all organisms.
Interdependent relationships
are established & allow for a
balanced use of aquatic
resources
                                For Comparison
 Black Angus beef versus Atlantic Salmon
      Hanging weight of Black Angus is 70% of live weight; edible meat is 42% of
      live weight.
    Gutted Atlantic salmon is 84% of live weight; salmon fillet is 50% of live
      weight.
 Benthos under a salmon cage chemically remediates in 6 month – 1 year; &
  biologically remediates in 2 years.
 An old growth forest cleared for cattle pasture will remediate in >200 years.

Type of food        Live weight   Edible portion   Yield   Spatial footprint   Remediation time
                        (kg)           (kg)                      (ha)              (years)
Atlantic salmon     2,500,000       1,250,000      0.50          1.6                  2
Angus beef cattle   2,976,190       1,250,000      0.42         6,982               >200