## *Chapter 6* 

## *Fisheries*  {#fisheries .unnumbered}

### Brief Description of the Sector {#brief-description-of-the-sector .unnumbered}

Aquatic resources make up a significant of the animal protein intake of
poor households in many parts of South East Asia. In countries such as
Thailand, Laos, Cambodia, and Vietnam, fish comprises between 50 to 85
percent of dietary protein intake. The fisheries sector is divided into
two major sub-sectors: capture fisheries and aquaculture. The term
"capture fisheries" is applied to the practice of harvesting wild fish
and other aquatic organisms. Both industrial and artisanal fishing
practices fall under this category.

Aquaculture is the practice of raising and harvesting fish and aquatic
organisms under controlled circumstances. Typically, aquaculture is used
to grow finfish (salmon, milkfish, carp, tilapia), mollusks (mussels,
oysters, clams), shrimp and seaweed. Aquaculture can be pursued in
fresh, brackish and salt-water bodies.

According to the Food and Agricultural Organization, Asia is the top
aquaculture- producing region in the world. However, the sustainability
of aquacultural practices is questionable. The most recent UNEP Global
Environment Outlook study underscored that over exploitation of fish
stocks in capture fisheries and poor aquacultural practices are of
concern in Bangladesh, India, Pakistan, Sri Lanka and other countries.

There are two basic modes of practicing aquaculture: intensive and
extensive. **Intensive aquaculture** subjects an organism to
hatchery-controlled conditions for most of the life cycle. This form is
most commonly applied to finfish. In salmon aquaculture, for example,
the fish are hatched, reared and fed in controlled ponds until they are
big enough to harvest. Extensive aquaculture usually involves
unsophisticated technology, relies on natural food and has a low
input-to-output ratio. Typically, only part of the life cycle is
controlled. Extensively operated fish ponds often rely on a supply of
young fish from the wild, and use minimal feed and fertilizer inputs.

Small-scale fisheries provide many benefits to both farmers and the
environment. For poor farmers, they are both a major cash crop and an
important source of protein. For local communities, aquaculture can
create employment and diversify income-generating activities. In
addition, aquaculture can serve as insurance against long-term
shortfalls in capture fishery yields. It can prevent over-exploitation
of finite stocks and minimize competition for land use. Moreover,
aquaculture can provide active benefits to water bodies, such as
improving productive capacity and water quality, converting polluting
waste products into fish protein, controlling the spread of diseases
such as malaria and schistosomiasis, and providing sewage treatment and
low-cost weed clearance in irrigation systems. Finally, wastes from
aquaculture can be used as fertilizer for agricultural production.

### Potential Environmental Impacts of Development Programs in the Sector and Their Causes  {#potential-environmental-impacts-of-development-programs-in-the-sector-and-their-causes .unnumbered}

Many of the impacts summarized below can be avoided through careful
resource management and through sound planning and design of small-scale
fisheries. Significant adverse impacts may include:

#### For Capture Fisheries {#for-capture-fisheries .unnumbered}

**Over-harvesting.** Widespread, unsustainable fishing practices have
left capture fisheries with a shrinking resource base. FAO estimates
that 11 of the world\'s 15 major fishing areas and 69 percent of the
world\'s major fish species are in decline and in urgent need of
management. Over-fishing by foreign fleets, has depleted local fish
stocks, forcing small-scale fishermen to fish further out to sea---a
safety hazard---or in protected areas such as marine national parks. As
harvests of valuable fish stocks decrease, fisherman are forced to
collect lower-value fish, resulting in less return on investment and
continuing the cycle of over-harvesting. (See the box on facing page.)

**By-catch.** Some types of fishing equipment---such as nets with small
mesh sizes, trawlers, and long lines---collect both the desired species
(catch) and many non-target species (by-catch). For example, driftnets
entangle and drown birds, sharks, whales and dolphins. Prompted by
governments and conservation groups around the world, the United Nations
banned large-scale driftnetting on the high seas in 1993. Smaller
driftnets, however, are still being used in coastal waters.

By-catch includes unwanted or undersized animals. These animals are
culled and returned to the sea, often dead or dying; the populations of
many non-target species are dropping as a result. In many cases, the
discarded animals are juveniles, which increases the rate of population
collapse.

**Toxic Substances.** Toxic substances, such as cyanide, and techniques
like dynamiting and electrocution are used to more easily harvest fish.
But cyanide, which anesthetizes fish for harvesting, also poisons coral
reefs and non-target organisms. Dynamite fishing, is practiced in many
parts of South East Asia. The Philippine islands are particularly prone
to these destructive activities that damage coral reefs and has caused
fisheries to decline in these areas.

Endangered Species. Due to a combination of over-harvesting, habitat
destruction and the introduction of exotic animals that compete with
native species, there are numerous threatened fish species in Asia --
the Mekong giant catfish (the largest scaleless freshwater fish in the
world) is one of many. Loss of fish populations leads to economic
hardship for artisan fishermen and reduces food security for the entire
population.

#### For Aquaculture {#for-aquaculture .unnumbered}

**Pollution.** Aquaculture systems cause pollution in a variety of ways:

-   Pond water discharged into coastal areas or streams can adversely
    affect sedimentation rates, the nutrient cycle, and dissolved oxygen
    (DO) levels, and can raise sedimentation rates, accelerate the
    nutrient cycle and lower dissolved oxygen levels. These changes can
    lead to eutrophication, a state where a water body is polluted with
    excess nutrients, which remove dissolved oxygen from the water and
    cause rapid plant growth, including toxic algal blooms. These toxins
    may concentrate in shellfish, creating a serious risk to human
    health. Degraded organic materials from pond bottoms release toxic
    sulfide compounds and ammonia into the water. The net result from
    these combined nutrient changes may be decreased water quality and
    increased stress on aquatic life, with damage to capture fisheries.

-   Feeding regimes for bred species often cause excess food to
    accumulate below aquaculture pens. This excess food is consumed by
    benthic (bottom-dwelling) organisms or is left to decompose.
    Decomposition causes degradation of water quality and decreasing
    oxygen levels in the water body, which can be fatal to aquatic
    organisms. Consumption by benthic organisms, on the other hand,
    disrupts the balance of the entire ecosystem.
    ![](media/image1.jpeg){width="2.361111111111111in"
    height="2.9034722222222222in"}

-   Fish wastes from intensive aquaculture, in combination with
    decomposing excess food, also cause algal blooms.

-   Anti-fouling agents are often used to prevent organism growth on
    cages and netting. Some anti-fouling agents, such as TBT, interfere
    with reproductive functions of both cultured and wild shellfish.

-   Human activities associated with aquaculture also generate
    pollution. Human wastes generated from habitation near aquaculture
    cages can degrade water quality and create health hazards. For ease
    of access, fish processing facilities are often located near
    fishponds or enclosures. If wastes from fish-processing activities
    are disposed of in fishponds, this also damages water quality.

**Habitat Destruction.** Because they are located in inter-tidal zones,
mangrove forests are often cleared for replacement by aquaculture ponds.
Mangroves, however, stabilize coastlines, reduce storm erosion, act as
spawning and nursery areas for many fish and crustacea, and generally
support a diverse population of grasses, birds, and other land-based and
aquatic animals. Mangroves also serve as a renewable resource, providing
firewood, timber, pulp, and charcoal for local communities. Destroying
mangroves has disastrous effects on the environment, including
destruction of shorelines and loss of fish breeding grounds. These
habitat changes may cause fish populations to collapse.

Wetlands are often converted to freshwater aquaculture ponds. This
results in flooding and loss of animal habitats, and adversely affects
downstream water quality.

**Impacts on freshwater sources.** Intensive aquaculture requires large
quantities of freshwater, usually obtained from groundwater or surface
freshwater bodies. This leaves less water available for downstream uses,
such as municipal water supply and agriculture. Pumping groundwater near
coastal areas may cause saltwater to enter the aquifer and contaminate
the underground reservoir. Groundwater extraction may also cause land
subsidence (i.e., the land surface slumps or collapses). If aquaculture
ponds are not designed properly, saltwater can seep into surface
reservoirs, canals and rice paddies. As noted above, pond water is often
discharged into freshwater bodies, adding excess nutrients and
pollutants and increasing salinity. Salt can also seep into freshwater
sources from poorly designed sediment disposal sites.

**Disease.** Intensive aquaculture uses a dense stocking rate with
intentional overcrowding. Overcrowding may induce stress in aquatic
organisms and increase their susceptibility to diseases. It also
contributes to poor water quality and the rapid growth and transmission
of parasites and pathogens, which may spread to wild populations and
local capture fisheries. To treat and prevent disease, a variety of
chemicals are used, including antibiotics, parasiticides
(parasite-killing drugs), pesticides, hormones, anesthetics,
pigments**,** minerals, and vitamins. These chemicals are generally used
in finfish or hatchery aquaculture, and applied along with feed. They
may disperse beyond the pens and affect non-target organisms.
Application of antibiotics also leads to the creation and spread of
antibiotic-resistant bacteria.

**Adverse effects on other** **organisms.** Organisms escaping from
aquaculture systems may have adverse impacts on wild populations.
Species bred or genetically engineered for aquaculture are selected for
high growth rates and/or disease resistance, usually at the expense of
other survival characteristics. If these animals compete and interbreed
with wild populations, the net result can be populations which are less
genetically diverse and possibly less resistant to environmental
changes.

If the escaping organisms are exotic to the area or water body into
which they escape, where they are used, they may interfere with the
food, habitat and spawning areas of native species. Non-native species
are also a source of new diseases and predators.

Nearly all marine and brackish water aquaculture requires inputs from
natural fisheries. Wild organisms or larvae are generally used as seed
stock for aquaculture operations. Collecting larvae or young animals, if
not done carefully, may depress the world population of the species to
dangerously low levels.

Aquaculture based on carnivorous organisms (such as salmon and shrimp)
requires large quantities of fishmeal. Fishmeal is manufactured from
harvests of "trash fish," fish not otherwise consumed by people. Growing
a pound of salmon may require 3--5 pounds of wild fish, and between 1985
and 1995 the world\'s shrimp farmers used 36 million tons of wild fish
to produce just 7.2 million tons of shrimp (Emerson 1999). Expanding
aquaculture by harvesting more trash fish may lead their populations to
collapse, not only making the aquaculture unsustainable but also
endangering other aquatic animals that feed on trash fish.

Clustering and poor siting of aquaculture facilities can obstruct access
to water resources by wild populations. Predators, often drawn to
aquaculture sites, may become entangled in net pens and drown.

**Adverse impacts on downstream users.** As mentioned previously,
intensive and semi-intensive aquaculture systems require large volumes
of fresh water, often drawn from surface waters. This practice leaves
less water available for downstream users. In rural areas, this results
in less water available to irrigate crops and forces women to travel
further to collect water for household use. Also, seepage and discharges
from fishponds can degrade the quality of water available to downstream
users, affecting drinking water, agriculture, capture fisheries and
recreational uses of water bodies.

###   {#section .unnumbered}

### Possible Environmental Impacts of Aquaculture Listed by Production Type[^1] {#possible-environmental-impacts-of-aquaculture-listed-by-production-type .unnumbered}

  ------------------------- ----------------------------------------------
  **Culture System**        Environmental Impact

  **Extensive**             

  1\. Seaweed culture       May occupy formerly pristine reefs; rough
                            weather losses; market competition;
                            conflicts/failures, social disruption.

  2\. Coastal bivalve       Public health risks and consumer resistance;
  culture (mussels,         microbial diseases, red tides, industrial
  oysters, clams, cockles)  pollution; rough weather losses; seed
                            shortages; market competition, especially for
                            export produce; failures, social disruption.

  3\. Coastal fishponds     Destruction of ecosystems, especially
  (mullet, milkfish,        mangroves; increasingly non-competitive with
  shrimp, tilapias)         more intensive systems; nonsustainable with
                            high population growth; conflicts/failures,
                            social disruption.

  4\. Pen and cage culture  Exclusion of traditional fishermen;
  in eutrophic waters       navigational hazards; conflicts, social
  and/or rich benthos       disruption; management difficulties; wood
  (carp, catfish, milkfish, consumption.
  tilapias)                 

  **Semi-intensive**        

  1\. Fresh- and brackish   Freshwater: health risks to farm workers from
  water pond (shrimp and    waterborne diseases. Brackish water:
  prawns, carp, catfish,    salinization/acidification of soils/aquifers.
  milkfish, mullet,         Both: market competition, especially for
  tilapias)                 export produce; feed and fertilizer
                            availability/prices; conflicts/failures,
                            social disruption.

  2\. Integrated            As for freshwater above, plus possible
  agriculture-aquaculture   consumer resistance to excreta-fed produce;
  (rice-fish;               competition from other users of fishmeal
  livestock/poultry-fish;   inputs (livestock and cereal production);
  vegetables-fish and all   toxic substances in livestock feeds (e.g.,
  combinations of these)    heavy metals) may accumulate in pond sediments
                            and fish; pesticides may accumulate in fish.

  3\. Sewage-fish culture   Possible health risks to farm workers, fish
  (waste treatment ponds;   processors and consumers; consumer resistance
  latrine and septic waste  to produce.
  used as pond inputs; fish 
  cages in wastewater       
  channels)                 

  4\. Cage and pen culture, As with extensive cage and pen systems above.
  especially in eutrophic   
  waters or on rich benthos 
  (carp, catfish, milkfish, 
  tilapias)                 
  ------------------------- ----------------------------------------------

  ------------------------------ ----------------------------------------
  **Intensive**                  

  1\. Freshwater, brackish water Effluents/drainage high in Biological
  and marine ponds (shrimp;      Oxygen Demand (BOD) and suspended
  fish, especially               solids; market competition, especially
  carnivores---catfish,          for export product; conflicts/failures,
  snakeheads, grouper, sea bass, social disruption.
  etc.)                          

  2\. Freshwater, brackish water Accumulation of anoxic sediments below
  and marine cage and pen        cages due to fecal and waste feed
  culture (finfish, especially   build-up; market competition, especially
  carnivores---grouper, sea      for export produce; conflicts/failures,
  bass, etc.---but also some     social disruption; consumption of wood
  omnivores such as common carp) and other materials.

  3\. Other---raceways, silos,   Effluents/drainage high in BOD and
  tanks, etc.                    suspended solids; many location-specific
                                 problems.
  ------------------------------ ----------------------------------------

### Sector Program Design---Some Specific Guidance  {#sector-program-designsome-specific-guidance .unnumbered}

As with other program and project development activities, potentially
damaging environmental impacts need to be addressed early in the design
process in order to avoid costly mistakes or project failure. Listed
here are good management practices and design criteria that can help
prevent adverse impacts.

#### Best Management Practices for Capture Fisheries {#best-management-practices-for-capture-fisheries .unnumbered}

-   Do not discharge toilets, washwater, non-oily bilge water, deck
    washwater, fish offal, or kitchen waste into coastal and sensitive
    waters.

-   Exclude motorized vessels from areas that contain important
    shallow-water habitats.

-   Establish no-wake zones for boats and ships to decrease erosion and
    turbidity.

-   Use oil-absorbing materials in bilge areas of a boat's inboard
    engine; dispose of and replace them appropriately (see chapter on
    "Solid Waste Management" in these guidelines).

-   Do not discharge bilge and ballast water with oil and grease
    concentration above 10 mg/liter.

-   Clean boats in the water by hand. Use detergents and cleaning
    compounds that are phosphate-free and biodegradable: for example, no
    TSP (trisodium phosphate). Do not use detergents containing ammonia,
    sodium hypochlorite, chlorinated solvents, petroleum distillates or
    lye.

#### Best Management Practices for Aquaculture {#best-management-practices-for-aquaculture .unnumbered}

##### General Guidelines for Site Selection for Aquaculture  {#general-guidelines-for-site-selection-for-aquaculture .unnumbered}

Proper site selection is critical to successful aquaculture projects. A
poor site will not only make an aquaculture project more difficult to
manage, but it may also destroy critical natural habitats, spread
disease and contaminate freshwater sources. Use the following general
guidelines for selecting a suitable aquaculture site:

-   Maintain adequate distance from other fish farming enterprises,
    natural spawning runs, restricted areas (national parks, world
    heritage areas, conservation areas) and sensitive ecosystems
    (including swamps, mangroves, mud flats, intertidal areas, bays,
    lakes, rivers, coral reefs, sea grass meadows, and shellfish beds).

-   Choose sites with adequate wave, current, and tidal patterns. Areas
    of high currents will minimize waste accumulation through
    hydrodynamic dispersal. Lower levels of waste allow excess nutrients
    to be more easily assimilated into the local food web. Currents and
    tides also help replenish anoxic water with oxygen-rich water from
    surrounding areas. Rotting vegetation in a water body is an
    indicator of stagnant water and should be avoided. Remember to check
    for seasonal water variations.

-   Do not use sites with incompatible users, such as riverbed sand
    extraction operations, harbors, sewage outfalls, oil platforms,
    shipping lanes, tanneries, sugar refineries and distilleries, or
    palm oil processing plants. Do not use sites polluted with
    chemicals, pesticides or heavy metals.

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-   Choose sites that are near wild stock populations. Avoid introducing
    exotic fish species into a body of water. Remember to consider
    predator populations, existing ecosystem relationships and pathogen
    concentrations.

##### Other General Guidelines for Aquaculture  {#other-general-guidelines-for-aquaculture .unnumbered}

-   Use hatchery stock where possible.

-   Use non-native species only where escape is impossible or where
    survival and reproduction under local conditions is impossible.

-   Use palatable feed with high utilization rates and low waste. Use
    feed of the appropriate size for the age of the stock. Feed often
    and at low levels to minimize waste. Distribute feed evenly.

-   Use pathogen-free stock. If necessary, quarantine and provide
    treatment.

-   Use drugs or pesticides only asas needed during a diseasen outbreak,
    not on a routine preventive basis. Delay harvest of treated stock
    and delay discharge of treated water until the drug or pesticide has
    degraded fully.

-   Apply Integrated Pest Management (IPM) to the aquaculture program.
    Aquaculture combined with rice production enables a farmer to grow
    two crops on the same land. The fish will consume algae and weeds,
    fertilize the water, and improve soil texture. Aquaculture in
    irrigation channels will control algae and weeds.

##### Specific Guidance for Pond Aquaculture {#specific-guidance-for-pond-aquaculture .unnumbered}

-   **Siting** **Ponds**

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-   Locate ponds where they do not cause a loss of habitats such as
    mangroves, wetlands, lagoons, rivers, inlets, bays, estuaries,
    swamps, marshes or high wildlife-use areas. Situate ponds away from
    tidal areas subject to flooding.

-   Choose sites with good soil, preferably clay-loam or sandy-clay,
    that will retain water and be suitable for building dikes. Soil
    should be alkaline (having a pH of 7 and above) to prevent problems
    that result from acid-sulphate soils (e.g., poor fertilizer
    response; low natural food production and slow growth of culture
    species; probable fish kills). Acidic and organic soils (e.g., high
    in humus or compost) are not suitable.

-   For saline brackish ponds, choose land with average elevation that
    can be watered by ordinary high tides and drained by ordinary low
    tides. Tidal fluctuation should be moderate, between two and three
    meters. Sites with tidal fluctuations above four meters require very
    large, expensive dikes to prevent flooding during high tide. Areas
    with slight tidal fluctuations, of one meter or less, cannot be
    properly drained or filled.

-   Provide a buffer zone for areas near riverbanks and coastal shores
    that are exposed to wave action.

-   Ensure that the area has a steady supply of water, in adequate
    quantities throughout the year. Water supply should be
    pollution-free and with a pH of 7.8--8.5.

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-   **Designing Ponds**

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-   Design to prevent storm and flood damage that could cause overflow
    discharges.

-   Provide settling ponds for the effluent, and also for water intake,
    if the water supply has high sediment loads.

-   Ensure that pond depth is shallow enough to prevent *stratification*
    (potentially dangerous layering of the pond water into a warmer
    upper layer and a cooler, dense, oxygen-poor lower layer). If not,
    include a means of providing aeration or other destratifying
    mechanisms.

-   Include reservoirs for water storage and treatment.

-   Isolate supply and effluent canals as far as possible from each
    other, and from other farms.

-   Where possible, use a closed or re-circulating system with
    treatment; do not use more than small amounts of fresh water to top
    off the pond.

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-   **Constructing Ponds**

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-   Line bottoms and sides of ponds, levees and canals with impervious
    material to prevent seepage into surrounding soils and groundwater.

-   Construct stormwater bypasses around the area of the ponds.

-   Dig ponds deep enough to control weed growth.

-   Minimize sediment erosion by:

    -   using gradual slopes in construction;

    -   planting vegetation on the surfaces of slopes;

    -   compacting and lining the banks;

    -   making discharge channels large enough to handle peak loads
        without scouring.

-   Construct wetlands to treat the settling pond water from freshwater
    ponds.

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-   **Operating Ponds**

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-   Operate ponds so that they do not cause a loss of, or damage to,
    habitats, including mangroves, lagoons, rivers, inlets, bays,
    estuaries, swamps, marshes and other wetlands, high wildlife use
    areas, reefs, parks, ecological reserves, or fishing grounds.

-   Screen pond entrances and exits to keep fish stock in and other
    animals out.

-   Discharge saline ponds into deep water with high currents.
    Discharging saline water into intertidal zones is not acceptable.

-   Prevent erosion by leaving sediment, unless removal is absolutely
    necessary.

-   Keep freshwater use to a minimum in brackish or saline ponds.

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-   **Monitoring and Controlling Ponds**

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-   Maintain water quality with aeration, sustainable stocking rates and
    controlled feeding rates, not with water exchange (replacing old
    pond water with clean water).

-   Treat effluent in settling ponds with filter feeders, and pass
    settling pond water from freshwater ponds through a constructed
    wetland before discharge.

-   Use the effluent as liquid fertilizer on crops, particularly forage
    crops where bare ground is minimal.

-   Monitor and control effluents before discharging to meet water
    quality standards for turbidity, suspended solids, BOD, pH,
    dissolved oxygen (DO), ammonia, nitrate, nitrite, disease organisms
    and pesticides. In freshwater ponds, monitor and control phosphorus.

-   Alternate freshwater ponds, where possible, and allow ponds to dry
    out, lie fallow, or grow a crop to reduce the need for sludge and
    nutrient removal.

-   Plow non-saline sludge into agricultural lands that are not
    susceptible to runoff and leaching.

-   Avoid discharge of saline ponds into freshwater habitats.

##### Specific Guidance for Net Pen Aquaculture {#specific-guidance-for-net-pen-aquaculture .unnumbered}

-   **Siting** **Net Pens**

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-   Locate all open-net pens in highly flushed, deep-water sites with no
    tidal reversals.

-   Site net pens at least one km from the mouths of streams or rivers
    when using fish that travel upstream to spawn.

-   Site net pens downcurrent of recreational areas, marine parks,
    fishing grounds, shellfish beds used for commercial or recreational
    harvest or other sensitive areas.

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-   **Constructing Net Pens**

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-   Construct all net pens to prevent breakup of facilities and loss of
    stock, wastes, feed or supplies even in severe weather conditions.

-   Keep boats from discharging sewage into the water by:

    -   constructing a shore facility with a proper septic system and
        drain field, tanks and pump-out or a small treatment plant,
        where conditions are suitable;

    -   using holding tanks and a pump-out boat to empty the tanks at
        regular intervals.

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-   **Operating Net Pens**

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-   Maintain sufficient storage capacity to handle even large,
    catastrophic fish kills caused by algal blooms or disease epidemics.

-   Provide adequate safe storage, with secondary containment, for
    drugs, fuels, solvents and toxic materials. Preferably, locate this
    storage on shore.

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-   **Monitoring and Controlling Net Pens**

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-   Place a bag or other container around all net pens to isolate
    diseased fish. The bag should be impermeable and capture all fish
    wastes. Arrange to treat and neutralize bag water or wastewater
    before discharge.

-   Collect and dispose of waste feed and feces from bagged or contained
    pens as compost. Collect and dispose of waste floatables, scum and
    oils from bagged or contained pens with other compost in a suitable
    facility.

-   Collect and dispose of unmarketable fish, blood and guts:

    -   with other compost in a suitable facility;

    -   by sending it to a rendering plant, or

    -   by sending it to a properly operated landfill.

-   Avoid discharges near or upcurrent of recreational areas, marine
    parks, fishing grounds, shellfish beds used for commercial or
    recreational harvest, or other sensitive areas.

### Environmental Mitigation and Monitoring Issues  {#environmental-mitigation-and-monitoring-issues .unnumbered}

Field studies of small-scale fishponds in Zimbabwe and Zambia have shown
a large number of project failures and pond abandonments. Reasons why
the projects failed include:

**Motivation.** Many farmers choose to dig fishponds in anticipation of
benefits or to associate themselves with a \"culture of development,"
rather than a belief in the technology. Such farmers may be discouraged
from continuing fish farming in the face of maintenance problems and/or
lack of short-term economic returns. Moreover, development organizations
and agencies often structure projects around false assumptions,
including:

-   Assuming members of fish farming households have equal authority in
    making decisions;

-   Assuming farmers frequently make decisions by weighing costs,
    benefits, and risks; and

-   Assuming fish production is the farmer's primary concern.

When these assumptions are not valid, the farmers may not be able to
resolve management and operational problems and will discontinue fish
farming.

**Environmental Factors.** Projects may fail due to uncontrollable
environmental disasters, such as droughts and floods. Also, if water
temperatures are too low, fish may not grow to adequate size in time for
harvesting.

**Biological Factors.** Farmers may experience problems maintaining
adequate stocking and survival rates.

**Financial Factors.** The project may not generate adequate or rapid
enough financial return, especially in systems requiring inputs of fish
feed. External factors like political unrest may disrupt access to
distant markets. Also, competition from capture fisheries may decrease
prices and prevent a project from reaching profitability.

**Social Factors.** Theft of tools and stocks can jeopardize project
success and reduce individual and community enthusiasm for aquaculture.

**Administrative Factors.** Extensive bureaucracy and poor
communications between farmers and project supporters may generate
distrust or apathy and result in project failure. Poor information
exchange, lack of extension services and lack of contingency planning
can each be fatal blows to a fishpond project.

#### External Environmental Conditions Affecting Project Success {#external-environmental-conditions-affecting-project-success .unnumbered}

Even with good management and design, fisheries projects are still at
risk from external environmental conditions which can prevent project
success. Types of trauma include:

**Exotic and Endangered Species**. Tightening controls on importation of
animals and plants will help prevent introduction of exotic species.
This policy, however, requires allocating resources to police borders
and entry points, and to enforce fines for breach of regulations; such
resources may not be available.

Alien plants can be physically removed by hand, by machinery or by
chemicals. Biological control can contain alien populations with fewer
environmental impacts. The latter, however, is a more lengthy process,
because control organisms must themselves be rigorously tested for
adverse impacts before their release into the environment.

**Pollution**. Fish life cycles can be adversely affected by pollution
from industries (including the fish processing industry), human
wastewater, nutrient loading and pesticides from agricultural runoff,
water body acidification from vehicle and power station emissions,
dredging, reclamation, sedimentation, dams, river channel modifications,
and alteration of freshwater drainage. Pollutants, including heavy
metals, pesticides and radioactive wastes, will bioaccumulate in fish
and mollusk populations.

Nutrient loading of a water body can best be mitigated at the
source---for example, by treating human effluent and capturing
agricultural runoff. Early-warning networks can monitor for toxic algal
blooms caused by excessive nutrient enrichment of water bodies. Instead
of closing water bodies during periods of seasonal contamination from
metals or hazardous wastes, mollusks can be grown in polluted water and
then purged in clean water sources before processing or sale.
Encouraging vegetative ground cover to prevent runoff, along with active
techniques like flushing and dredging the water body, can help mitigate
pollution from sedimentation.

**Habitat destruction.** Mangroves are particularly susceptible to being
encroached upon by aquaculture. In fact, more than 60 percent of Asia's
mangroves have already been converted to aquaculture farms. According to
the FAO, "Industrialization, urbanization, deforestation, mining, and
agricultural land and water use often cause degradation of aquatic
environments, the greatest threat to inland fish production" (FAO 1999).
Fishery resources are damaged when:

-   aquatic habitats are destroyed or fragmented;

-   bodies of water are impounded (dammed) or channeled;

-   too much water is drawn or diverted, or

-   soil becomes eroded.

Manipulation of the hydrological characteristics of rivers, lakes and
flood plains may also do significant harm.

Coral reefs are adversely affected by human activities such as sediment
runoff from deforestation, eutrophication, bleaching, disease, dynamite
and chemical fishing, anchor damage, dredging, and groundings from ship
traffic.

Controlling damaging activities such as pollution, sedimentation,
over-fishing, etc., can help mitigate habitat destruction. Replanting
denuded areas can often restore mangrove habitats. Coral reefs are more
difficult to restore and are highly sensitive to environmental stress.
Thus, it is crucial to monitor coral ecosystems for changes in
temperature, sedimentation, nutrient loading, storm damage and toxins.

+-----+----+-----------+--------+------------------------------------+
| **A | ** |           | **App  | **Mitigation Techniques**          |
| cti | Pr |           | licabi |                                    |
| vit | ob |           | lity** |                                    |
| y** | le |           |        |                                    |
|     | m/ |           |        |                                    |
|     | Im |           |        |                                    |
|     | pa |           |        |                                    |
|     | ct |           |        |                                    |
|     | ** |           |        |                                    |
+=====+====+===========+========+====================================+
| **  |    |           |        |                                    |
| All |    |           |        |                                    |
| Fi  |    |           |        |                                    |
| she |    |           |        |                                    |
| rie |    |           |        |                                    |
| s** |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | P  |           | M      | Mollusks are particularly          |
|     | ol |           | ollusk | vulnerable to biocides, leachates, |
|     | lu |           |        | metals and pesticides. Monitor     |
|     | ti |           |        | water conditions closely for       |
|     | on |           |        | contaminants.                      |
+-----+----+-----------+--------+------------------------------------+
| **C |    |           |        |                                    |
| apt |    |           |        |                                    |
| ure |    |           |        |                                    |
| Fi  |    |           |        |                                    |
| she |    |           |        |                                    |
| rie |    |           |        |                                    |
| s** |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
| D   | O  |           | C      | Set minimum size limit for         |
| esi | ve |           | apture | harvested fish.\                   |
| gn/ | r- |           | fis    | Use bag limits.\                   |
|     | ha |           | heries | Use appropriate fishing gear.      |
| O   | rv |           |        | Choose the largest possible size   |
| per | es |           |        | of mesh in fishing nets.\          |
| ati | ti |           |        | Close seasons during critical      |
| ons | ng |           |        | stages in fish life cycles.        |
+-----+----+-----------+--------+------------------------------------+
|     | By |           | C      | Use mesh sizes that allow small    |
|     | -c |           | apture | and juvenile fish to escape.\      |
|     | at |           | fis    | Use a square mesh, or a mesh with  |
|     | ch |           | heries | square windows, instead of a       |
|     | (  |           |        | diamond-shaped mesh.               |
|     | ca |           |        | (Diamond-shaped mesh constricts    |
|     | tc |           |        | during towing.)\                   |
|     | hi |           |        | Use a by-catch reduction device to |
|     | ng |           |        | allow large animals to escape from |
|     | fi |           |        | nets.                              |
|     | sh |           |        |                                    |
|     | a  |           |        |                                    |
|     | nd |           |        |                                    |
|     | o  |           |        |                                    |
|     | th |           |        |                                    |
|     | er |           |        |                                    |
|     | a  |           |        |                                    |
|     | qu |           |        |                                    |
|     | at |           |        |                                    |
|     | ic |           |        |                                    |
|     | a  |           |        |                                    |
|     | ni |           |        |                                    |
|     | ma |           |        |                                    |
|     | ls |           |        |                                    |
|     | th |           |        |                                    |
|     | at |           |        |                                    |
|     | a  |           |        |                                    |
|     | re |           |        |                                    |
|     | t  |           |        |                                    |
|     | oo |           |        |                                    |
|     | s  |           |        |                                    |
|     | ma |           |        |                                    |
|     | ll |           |        |                                    |
|     | or |           |        |                                    |
|     | of |           |        |                                    |
|     | t  |           |        |                                    |
|     | he |           |        |                                    |
|     | w  |           |        |                                    |
|     | ro |           |        |                                    |
|     | ng |           |        |                                    |
|     | sp |           |        |                                    |
|     | ec |           |        |                                    |
|     | ie |           |        |                                    |
|     | s) |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | U  |           | C      | Educate fishermen about the        |
|     | se |           | apture | long-term environmental and        |
|     | of |           | fis    | economic damage from using cyanide |
|     | h  |           | heries | or dynamite on ecosystems.         |
|     | az |           |        |                                    |
|     | ar |           |        |                                    |
|     | do |           |        |                                    |
|     | us |           |        |                                    |
|     | su |           |        |                                    |
|     | bs |           |        |                                    |
|     | ta |           |        |                                    |
|     | nc |           |        |                                    |
|     | es |           |        |                                    |
|     | a  |           |        |                                    |
|     | nd |           |        |                                    |
|     | te |           |        |                                    |
|     | ch |           |        |                                    |
|     | ni |           |        |                                    |
|     | qu |           |        |                                    |
|     | es |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
| **A |    |           |        |                                    |
| qua |    |           |        |                                    |
| cul |    |           |        |                                    |
| tur |    |           |        |                                    |
| e** |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
| Des |    |           |        |                                    |
| ign |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | Si | Mangrove  | G      | Always leave the most productive   |
|     | te | habitats  | eneral | mangrove stands intact.\           |
|     | s  |           |        | Use already cleared land whenever  |
|     | el |           |        | possible. Reuse existing ponds     |
|     | ec |           |        | before creating new ones.\         |
|     | ti |           |        | Site ponds on the landward side of |
|     | on |           |        | the mangroves; leave the seaward   |
|     |    |           |        | side undisturbed.\                 |
|     |    |           |        | Ponds should have a small surface  |
|     |    |           |        | area (footprint) relative to total |
|     |    |           |        | mangrove area. Ponds should be     |
|     |    |           |        | spaced well apart.\                |
|     |    |           |        | Mangroves should be retained and   |
|     |    |           |        | replanted in the middle, or on the |
|     |    |           |        | banks, of ponds.                   |
+-----+----+-----------+--------+------------------------------------+
|     |    | Adequate  | F      | Avoid shallow areas and areas with |
|     |    | water     | infish | aquatic vegetation.\               |
|     |    | supply    |        | Place units in an area with a good |
|     |    | and       |        | current flowing through it. The    |
|     |    | ci        |        | action of the current helps water  |
|     |    | rculation |        | move through the cage system,      |
|     |    |           |        | removing metabolites and           |
|     |    |           |        | replenishing oxygen.\              |
|     |    |           |        | Depending on the direction of      |
|     |    |           |        | prevailing winds and currents,     |
|     |    |           |        | orient the cages to prevent debris |
|     |    |           |        | from collecting between them.      |
+-----+----+-----------+--------+------------------------------------+
|     | C  |           | G      | Filter feeders---organisms that    |
|     | on |           | eneral | strain their food out of the       |
|     | tr |           |        | waiter---improve water quality by  |
|     | ol |           |        | consuming plankton and preventing  |
|     | of |           |        | eutrophication. Consider growing   |
|     | nu |           |        | mollusks or seaweeds in            |
|     | tr |           |        | conjunction with other species, to |
|     | ie |           |        | reduce nutrient loading.           |
|     | nt |           |        |                                    |
|     | l  |           |        |                                    |
|     | oa |           |        |                                    |
|     | di |           |        |                                    |
|     | ng |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | C  |           | G      | Build ponds on soils with adequate |
|     | on |           | eneral | clay content.                      |
|     | tr |           |        |                                    |
|     | ol |           |        |                                    |
|     | of |           |        |                                    |
|     | s  |           |        |                                    |
|     | ee |           |        |                                    |
|     | pa |           |        |                                    |
|     | ge |           |        |                                    |
|     | in |           |        |                                    |
|     | to |           |        |                                    |
|     | gr |           |        |                                    |
|     | ou |           |        |                                    |
|     | nd |           |        |                                    |
|     | a  |           |        |                                    |
|     | nd |           |        |                                    |
|     | s  |           |        |                                    |
|     | ur |           |        |                                    |
|     | fa |           |        |                                    |
|     | ce |           |        |                                    |
|     | wa |           |        |                                    |
|     | te |           |        |                                    |
|     | rs |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | I  |           | M      | Use off-bottom systems such as     |
|     | mp |           | ollusk | rafts and lines.                   |
|     | ac |           | C      |                                    |
|     | ts |           | ulture |                                    |
|     | to |           |        |                                    |
|     | po |           |        |                                    |
|     | nd |           |        |                                    |
|     | f  |           |        |                                    |
|     | lo |           |        |                                    |
|     | or |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | E  |           | G      | Plan for seasonal constraints.\    |
|     | ro |           | eneral | Use settling ponds or other        |
|     | si |           |        | control structures.                |
|     | on |           |        |                                    |
|     | of |           |        |                                    |
|     | p  |           |        |                                    |
|     | on |           |        |                                    |
|     | ds |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | D  |           | F      | Locate cages where disturbances    |
|     | is |           | infish | from people and animals can be     |
|     | ea |           |        | minimized.                         |
|     | se |           |        |                                    |
|     | pr |           |        |                                    |
|     | ev |           |        |                                    |
|     | en |           |        |                                    |
|     | ti |           |        |                                    |
|     | on |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
| Con |    |           |        |                                    |
| str |    |           |        |                                    |
| uct |    |           |        |                                    |
| ion |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | E  |           | G      | Minimize disturbance of soil and   |
|     | ro |           | eneral | vegetation.                        |
|     | si |           |        |                                    |
|     | on |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | C  |           | M      | Do not seed mollusks too closely   |
|     | on |           | ollusk | together or they will generate     |
|     | tr |           |        | anoxic conditions (i.e., remove    |
|     | ol |           |        | all oxygen from the water).        |
|     | of |           |        |                                    |
|     | d  |           |        |                                    |
|     | is |           |        |                                    |
|     | so |           |        |                                    |
|     | lv |           |        |                                    |
|     | ed |           |        |                                    |
|     | ox |           |        |                                    |
|     | yg |           |        |                                    |
|     | en |           |        |                                    |
|     | su |           |        |                                    |
|     | pp |           |        |                                    |
|     | ly |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
| O   |    |           |        |                                    |
| per |    |           |        |                                    |
| ati |    |           |        |                                    |
| ons |    |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | O  |           | G      | Use high-quality feed.\            |
|     | ve |           | eneral | Feed the right amounts at the      |
|     | rf |           |        | right time.\                       |
|     | ee |           |        | Use feed pellets designed to float |
|     | di |           |        | longer in the water column.\       |
|     | ng |           |        | Instead of fishmeal, use meals     |
|     |    |           |        | made from terrestrial animal       |
|     |    |           |        | byproducts, plant oilseeds and     |
|     |    |           |        | grain legumes; from yeast; or from |
|     |    |           |        | cereal byproducts.                 |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | F      | Consider culturing herbivorous     |
|     |    |           | infish | fish that do not require feed      |
|     |    |           |        | inputs.                            |
+-----+----+-----------+--------+------------------------------------+
|     | Ov |           | G      | Use lower stocking densities.      |
|     | er |           | eneral |                                    |
|     | cr |           |        |                                    |
|     | ow |           |        |                                    |
|     | di |           |        |                                    |
|     | ng |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | D  |           | G      | Stock certified pathogen-free      |
|     | is |           | eneral | fish.\                             |
|     | ea |           |        | Use lower stocking densities.\     |
|     | se |           |        | Vaccinate fish.\                   |
|     | pr |           |        | Isolate diseased fish in bags,     |
|     | ev |           |        | rather than nets.\                 |
|     | en |           |        | Allow net pens to sit fallow       |
|     | ti |           |        | between stockings.\                |
|     | on |           |        | Apply IPM.\                        |
|     |    |           |        | Filter or ozonate the effluent     |
|     |    |           |        | from pond and recirculating tank   |
|     |    |           |        | systems.                           |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | F      | Avoid unnecessary or excessive     |
|     |    |           | infish | handling of fish; this will        |
|     |    |           |        | minimize stress and prevent        |
|     |    |           |        | disease.\                          |
|     |    |           |        | Avoid unnecessary disturbance of   |
|     |    |           |        | the fish by restricting activities |
|     |    |           |        | around the cage site.\             |
|     |    |           |        | Promptly remove diseased and dying |
|     |    |           |        | fish.\                             |
|     |    |           |        | During disease outbreaks, retain   |
|     |    |           |        | aquaculture effluent to prevent    |
|     |    |           |        | disease from spreading to wild     |
|     |    |           |        | populations.                       |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | Shrimp | Consider treating influent water   |
|     |    |           |        | supply (for example, with          |
|     |    |           |        | chlorine) to eliminate pathogens   |
|     |    |           |        | and carriers; this may reduce      |
|     |    |           |        | disease incidence and associated   |
|     |    |           |        | use of chemicals.                  |
+-----+----+-----------+--------+------------------------------------+
|     | Ex |           | G      | Treat aquaculture and human wastes |
|     | ce |           | eneral | according to sanitation            |
|     | ss |           |        | guidelines.\                       |
|     | of |           |        | Use polyculture to consume excess  |
|     | o  |           |        | nutrients.\                        |
|     | rg |           |        | Do not discharge nutrient-enriched |
|     | an |           |        | water into freshwater bodies.      |
|     | ic |           |        |                                    |
|     | n  |           |        |                                    |
|     | ut |           |        |                                    |
|     | ri |           |        |                                    |
|     | en |           |        |                                    |
|     | ts |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | F      | Move fish pens to different        |
|     |    |           | infish | locations periodically to prevent  |
|     |    |           |        | buildup of fish wastes and         |
|     |    |           |        | sediments below cages.\            |
|     |    |           |        | Manage fish wastes through bag     |
|     |    |           |        | systems, fallowing, vacuuming or   |
|     |    |           |        | harrowing.                         |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | Shrimp | Avoid frequent draining of shrimp  |
|     |    |           |        | ponds in order to allow microbial  |
|     |    |           |        | processes and deposition to remove |
|     |    |           |        | nutrients and organic matter from  |
|     |    |           |        | within. This will also conserve    |
|     |    |           |        | freshwater.\                       |
|     |    |           |        | Use aeration and water circulation |
|     |    |           |        | to break down organic matter and   |
|     |    |           |        | minimize anaerobic sediment        |
|     |    |           |        | accumulation at the bottom of      |
|     |    |           |        | shrimp ponds. Aeration may also    |
|     |    |           |        | remove ammonia.\                   |
|     |    |           |        | Use settling ponds to treat        |
|     |    |           |        | suspended solids.\                 |
|     |    |           |        | Always settle effluents released   |
|     |    |           |        | at the time of harvest.            |
+-----+----+-----------+--------+------------------------------------+
|     | In |           | G      | Use seaweed to oxygenate the water |
|     | ad |           | eneral | and to improve water quality by    |
|     | eq |           |        | removing ammonia and phosphorus.   |
|     | ua |           |        |                                    |
|     | te |           |        |                                    |
|     | d  |           |        |                                    |
|     | is |           |        |                                    |
|     | so |           |        |                                    |
|     | lv |           |        |                                    |
|     | ed |           |        |                                    |
|     | ox |           |        |                                    |
|     | yg |           |        |                                    |
|     | en |           |        |                                    |
|     | su |           |        |                                    |
|     | pp |           |        |                                    |
|     | ly |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | A  |           | G      | Use IPM or polyculture to control  |
|     | dv |           | eneral | weeds.\                            |
|     | er |           |        | Construct deeper ponds.\           |
|     | se |           |        | Consider use of less-toxic         |
|     | i  |           |        | alternatives to hazardous          |
|     | mp |           |        | products.\                         |
|     | ac |           |        | Designate areas for storage and   |
|     | ts |           |        | refueling. Apply chemicals with    |
|     | fr |           |        | proper containment away from       |
|     | om |           |        | watercourses or wetlands.\         |
|     | u  |           |        | Prepare an Emergency Spill        |
|     | se |           |        | Response Plan.\                    |
|     | of |           |        | Contain spills and treat           |
|     | an |           |        | contaminated soil and water as     |
|     | ti |           |        | required.                          |
|     | -f |           |        |                                    |
|     | ou |           |        |                                    |
|     | li |           |        |                                    |
|     | ng |           |        |                                    |
|     | c  |           |        |                                    |
|     | he |           |        |                                    |
|     | mi |           |        |                                    |
|     | ca |           |        |                                    |
|     | ls |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     | E  |           | G      | Consult extended-range weather     |
|     | ro |           | eneral | forecasts.\                        |
|     | si |           |        | Predetermine shutdown criteria for |
|     | on |           |        | bad weather conditions.\           |
|     |    |           |        | Maintain vegetated buffer zones.\  |
|     |    |           |        | Stabilize disturbed areas as soon  |
|     |    |           |        | as possible.\                      |
|     |    |           |        | Monitor sediment in water and      |
|     |    |           |        | treat as required prior to         |
|     |    |           |        | release.                           |
+-----+----+-----------+--------+------------------------------------+
|     | P  |           | G      | Use properly tensioned netpen      |
|     | re |           | eneral | lines and thick ropes to avoid     |
|     | da |           |        | entanglement from birds or aquatic |
|     | ti |           |        | animals.\                          |
|     | on |           |        | Use double nets to reduce          |
|     | (  |           |        | predation.\                        |
|     | wi |           |        | Rotate deterrence techniques to    |
|     | ld |           |        | give predators less opportunity to |
|     | a  |           |        | get used to a particular           |
|     | ni |           |        | technique.                         |
|     | ma |           |        |                                    |
|     | ls |           |        |                                    |
|     | ea |           |        |                                    |
|     | ti |           |        |                                    |
|     | ng |           |        |                                    |
|     | a  |           |        |                                    |
|     | qu |           |        |                                    |
|     | ac |           |        |                                    |
|     | ul |           |        |                                    |
|     | tu |           |        |                                    |
|     | re |           |        |                                    |
|     | f  |           |        |                                    |
|     | is |           |        |                                    |
|     | h) |           |        |                                    |
+-----+----+-----------+--------+------------------------------------+
|     |    |           | F      | Place protective netting on the    |
|     |    |           | infish | sides and tops of cages to protect |
|     |    |           |        | fish from bird and mammal          |
|     |    |           |        | predation.\                        |
|     |    |           |        | Place the nets as far from the     |
|     |    |           |        | cages as possible, and weight them |
|     |    |           |        | to prevent them from being pushed  |
|     |    |           |        | together by water movement.\       |
|     |    |           |        | Choose a size of net mesh that     |
|     |    |           |        | will prevent birds from becoming   |
|     |    |           |        | entangled.                         |
|     |    |           |        |                                    |
|     |    |           |        | Bird predation can be reduced by:  |
|     |    |           |        |                                    |
|     |    |           |        | -   eliminating safe roosting and  |
|     |    |           |        |     perching places;               |
|     |    |           |        |                                    |
|     |    |           |        | -   placing the containment units  |
|     |    |           |        |     deeper below the surface of    |
|     |    |           |        |     the water to reduce the        |
|     |    |           |        |     attraction of surface-feeding  |
|     |    |           |        |     birds such as gulls;           |
|     |    |           |        |                                    |
|     |    |           |        | -   moving young/small stock to an |
|     |    |           |        |     area where they are less       |
|     |    |           |        |     accessible to predatory birds; |
|     |    |           |        |                                    |
|     |    |           |        | -   placing nets above cages to    |
|     |    |           |        |     keep birds off;                |
|     |    |           |        |                                    |
|     |    |           |        | -   adjusting top nets so they do  |
|     |    |           |        |     not sag under the weight of    |
|     |    |           |        |     preying birds, enabling them   |
|     |    |           |        |     to more easily reach the fish; |
|     |    |           |        |                                    |
|     |    |           |        | -   using brightly colored nets to |
|     |    |           |        |     reduce the likelihood of birds |
|     |    |           |        |     accidentally swimming into     |
|     |    |           |        |     nets.                          |
+-----+----+-----------+--------+------------------------------------+

### Resources and References {#resources-and-references .unnumbered}

#### References {#references .unnumbered}

Aguilar-Manjarrez, J. and S.S. Nath (1998). *A Strategic Reassessment of
Fish Farming Potential in Africa.* CIFA Technical Paper No. 32. Rome,
FAO. 170p. <http://www.fao.org/docrep/W8522e/W8522E00.htm>

Baluyut, Elvira (1989). *Aquaculture Systems and Practices: A Selected
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FAO, 2000. *Small Ponds Make a Big Difference: Integrating Fish with
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Haylor, G. and S. Bland (2001). "Integrating Aquaculture into Rural
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Hishamunda, Nathanael, Maria Thomas et al. (1998). *Small-scale* *Fish*
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IIRR, IDRC, FAO, NACA and ICLARM. 2001. Source IIRR, IDRC, FAO, NACA and
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Machena, C. and J. Moehl (2001). "Sub-Saharan African Aquaculture:
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Tacon, A.G..J. (2001). "Increasing the Contribution of Aquaculture for
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#### Resources {#resources .unnumbered}

-   ***A Brief for Fisheries Policy Research in Developing
    Countries***. M. Ahmed, C. Delgado and S. Sverdrup-Jensen (1997).
    16 p. ISBN 971-8709-59-2. Available at:
    <http://www.cgiar.org/iclarm/pubsof/newbooks.html#towards>

Outcome of the International Consultation on Fisheries Policy Research
in Developing Countries, jointly organized by International Center for
Living Aquatic Resources Management (ICLARM), the International Food
Policy Research Institute and the Institute for Fisheries Management and
Coastal Community Development, and held 3-5 June 1997 at the North Sea
Centre, Hirtshals, Denmark. Forty-two scientists, academicians and
policymakers from developing countries, together with representatives
from donor and international organizations, contributed to the
development of a set of recommendations that include: (1) policy
research priorities and an agenda for international and national
research initiatives; and (2) guidelines for improving the capacity of
developing country institutions in fisheries' policy research, including
enlargement of the scope for collaborative research.

-   ***A Roadmap For the Future for Fisheries and Conservation***. M.J.
    Williams, Ed. (1998). ICLARM Conf. Proc. 56, 58 p. ISSN 0115-4435,
    ISBN 8709-94-0. Available at:
    <http://www.cgiar.org/iclarm/pubsof/newbooks.html#towards>

These proceedings report on the fisheries session of the Marine and
Coastal Workshop convened by IUCN, the World Conservation Union, 17--18
October 1998. The workshop sought to present and review the state of the
art in marine and coastal conservation and sustainable development
issues, and to discuss and develop directions, priorities and the role
of IUCN in addressing these issues. The seven papers in the book discuss
views from fisheries, conservation and resource management experts. The
consensus expressed is that fisheries conservation is becoming more
complex: it was previously the domain of fishers, fisheries managers and
scientists, but now multipolar interests are concerned, including
fishers and fisheries experts, consumers, local communities, civil
society and other economic sectors.

-   ***Code of Conduct for Responsible Fisheries***. FAO. Available at:
    <http://www.fao.org/fi/agreem/codecond/ficonde.asp>

This code sets out principles and international standards of behavior
for responsible practices, with a view to ensuring the effective
conservation, management and development of living aquatic resources,
with due respect for ecosystems and biodiversity. The code recognizes
the nutritional, economic, social, environmental and cultural importance
of fisheries, and the interests of all those concerned with the
fisheries sector. The code takes into account the biological
characteristics of the resources and affected environment. It also
addresses the interests of consumers and other users. All those involved
in fisheries are encouraged to apply the code and give effect to it.

-   ***Co-management in Small-Scale Fisheries. A Synthesis of Southern
    and West African Experiences***. (1998) Paper presented at IASCP
    conference in Vancouver, Canada, 9--14 June. In: *Fisheries
    Co-management in Africa.* Proceedings from a regional workshop on
    fisheries co-management research held 18--20 March 1997 in Mangochi,
    Malawi. \[16\]. Available at: <http://www.ifm.dk/reports/16.PDF>

This presentation summarizes the findings from eight African countries
where case studies of co-management arrangements in artisanal fisheries
were undertaken during the period 1996--97. In most of the cases,
co-management represents a new approach to fisheries management. In some
cases, it has only been applied within the last 3--5 years, and in a few
it is merely being considered as an option. The comparison of cases at
this early stage may help address critical issues in the planning and
implementation of fisheries co-management in Africa. These include the
provision of incentives for fishers and other stakeholders to cooperate
among themselves and with government in managing fisheries. The level of
cooperation is determined by key factors affecting the local
politico-historical, biophysical, economic and sociocultural
environments of fishing communities and associated fisheries. Incentives
for cooperation are determined by the character of the decision-making
arrangements in place. These include setting collective choice rules
and, in particular, the operational rules for a fishery, and thus the
legitimacy of the arrangements in the eyes of the fishers. The
co-management approach is intended to replace ineffective conventional,
centralized management systems. The differing bio-physical environments
seen in the cases represent three ecological systems: lake/reservoir,
lagoon/estuary and open coast. In most of the cases only a few fish
species are target species. These are often subject to heavy fishing
pressure or are already over-fished. In most cases the fishers and their
families are totally dependent on the fishery for their livelihood
since, with few exceptions, they have no alternative sources of income.

-   Alyanak, Leyla. *Fisherpeople launch patrol of their own slack
    waters*. FAO, 1996. <http://www.fao.org/news/1997/970102-e.htm>

Account of community-based management of Lake Malombe.

-   ***FAO Technical Guidelines for Responsible Fisheries*** (1997). No.
    5: Aquaculture Development. FAO, UN, Rome. 40 pp. Available at:
    <http://www.fao.org/>

-   "Farming fish the right way". R. Kapadia and M. Williams (2000).
    ICLARM, USAID. ICLARM Focus for research, 3(2), April, 4 p. USAID
    order no. PN-ACK-990.

```{=html}
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```
-   ***Fisheries and Aquaculture in Sub-Saharan Africa: Situation and
    Outlook in 1996*** (1996) FAO Fisheries Circular No. 922 FIPP/C922,
    ISSN 0429-9329. Rome. Available at:
    <http://www.fao.org/fi/publ/circular/c922/c922-1.asp>

The contribution of the fisheries sector to the economy of the region
has been largely beneficial. Over the last decade, significant progress
has taken place including strengthened artisanal fisheries development;
the consolidation of a small industrial base; growing export receipts
leading to a positive trade balance; and, more recently, indications of
a promising takeoff for aquaculture. However, in marine capture
fisheries, most bottom-dwelling stocks are thought to be fully
exploited, and catches by distant-water nations are steadily decreasing.
The immediate potential for increases in production and supply for local
markets is primarily with lower-value small pelagics species. Inland
fisheries figure importantly in food security, providing over 40 percent
of domestic catches.

Freshwater production is close to its estimated potential. Since 1990,
per-capita fish supply has followed an alarming downward trend. The
major challenge for the fisheries sector will be to maintain production
to meet current levels of demand. This will require significant efforts
to improve the management of capture fisheries, to support the
development of aquaculture, and to promote intra-regional trade.

-   ***Fisheries and Aquaculture Research Planning Needs for Africa and
    West Asia***. J.H. Annala, Ed. (1997). ICLARM Conf. Proc. 50, 80 p.
    ISSN 0115-4435, ISBN 971-8709-67-3. Available at:
    <http://www.cgiar.org/iclarm/icpub2.htm>

Proceedings of the ICLARM workshop on 23--25 September 1995 in Cairo,
Egypt. Discussion of coral reef resource systems; coastal aquatic and
inland aquatic resource systems; African Great Lake and reservoir
resource systems; social sciences and co-management; and the
partnerships between national aquatic research systems and ICLARM in
Africa and West Asia.

-   ***Fisheries Policy Research in Developing Countries: Issues,
    Priorities and Needs***. M. Ahmed, C. Delgado, S. Sverdrup-Jensen
    and R.A.V. Santos, Eds. (1999). ICLARM Conf. Proc. 60, 112 p. ISSN
    0115-4435, ISBN 971-802-005-5. Available at:
    <http://www.cgiar.org/iclarm/pubsof/newbooks.html#towards>

Organized into three sessions, the first session focused on policy
issues related to major changes in the demand and supply of fish. The
second session focused on the impact of fisheries policies on food
security and the environment. The third session was a discussion of
priority areas for fisheries policy research targeted to developing
countries. Regional and global fisheries policy issues, recommended
topics for fisheries policy research in developing countries and
implementation strategies were also discussed.

-   ***Forgotten Waters: Freshwater and Marine Ecosystems in
    Africa---Strategies for Biodiversity Conservation and Sustainable
    Development***. Caroly A. Shumway USAID (1999), x, 167 p. Available
    at: <http://www.dec.org/pdf_docs/PNACF449.pdf> Electronic copy cost:
    \$2.00

This report provides a primer on Africa\'s threatened aquatic
biodiversity, along with lessons learned from successful and failed
conservation projects and options for biodiversity conservation. The
report provides an overview of the value of aquatic biodiversity,
identifies the biologically and socio-economically most important sites,
discusses threats, and recommends activities for urgent conservation
action. The report addresses both freshwater and marine biodiversity,
covering the following aquatic habitats and their associated flora and
fauna: lakes, rivers, and streams; wetlands, including floodplains,
freshwater swamps (also known as marais), mangroves, and coastal
wetlands; and coral reefs. Associated wildlife include all terrestrial
and aquatic organisms whose survival depends on wet habitats. Ocean
pelagic areas are addressed briefly. Key recommendations include:
improve institutional capacity for aquatic resource management;
encourage appropriate economic and sectoral policies; involve the
community in aquatic resource conservation and management; support
needed research; mimic natural disturbance regimes in order to maintain
or restore natural hydrological cycles; assist in establishing critical
aquatic resources that can provide both conservation and fisheries
benefits; and assist in developing fisheries that are compatible with
biodiversity goals. Includes bibliography.

-   ***Research for the Future Development of Aquaculture in
    Ghana***. M. Prein, J.K. Ofori and C. Lightfoot, eds. (1996). ICLARM
    Conf. Proc. 42, 94 p. ISSN 0115-4435, ISBN 971-8709-43-6. Available
    at: <http://www.cgiar.org/iclarm/icpub2.htm>

Proceedings of a workshop held in Accra, Ghana, 11--13 March 1993, which
presented the preliminary results of a project entitled \"Research for
the Future Development of Aquaculture in Ghana.\" The project was funded
by the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ), and
was executed by ICLARM in collaboration with the Institute of Aquatic
Biology (IAB), Accra, Ghana. The aim of the project was to determine
\"what makes sense\" for aquaculture development in Ghana, focusing on
smallholder farmers.

-   ***Sustainable Aquaculture: Seizing Opportunities to Meet Global
    Demand*** (1998). Rural Development Department, The World Bank.
    Agriculture Technology Notes No. 22, December. Available at:
    <http://wbln0018.worldbank.org/essd/essd.nsf/rural+development/aquaculture>

This document reviews the continuing growth and importance of
aquaculture globally. According to FAO statistics, 1995 worldwide
production from aquaculture represented about 21.3 million tons (19
percent) of the total annual fish production from all sources.
Aquaculture grew at an annual average rate of 10 percent during the last
decade. In contrast, during the same period, the catch of wild fish from
both inland and marine waters (capture fisheries) averaged an annual
growth rate of less than 2 percent. Moreover, the contribution of
aquaculture to human nutrition between 1990 and 1995 increased, while
that from capture fisheries declined by about 10 percent. This reversal
occurred because an increasing percentage of the wild catch are species
of lower value that are being used to produce fishmeal for feed and
fertilizer.

-   ***The Third International Symposium on Tilapia in Aquaculture***.
    R.S.V. Pullin, J. Lazard, M. Legendre, J.B. Amon Kothias and D.
    Pauly, Editors (1996). ICLARM Conf. Proc. 41, 575 p. ISSN 0115-4435,
    ISBN 971-8709-42-8. Available at:
    http://www.cgiar.org/iclarm/pubsof/newbooks.html#towards

The proceedings of the Third International Symposium on Tilapia in
Aquaculture held in November 1991 in Abidjan, Côte d'Ivoire. The
conference reviewed the latest research and discussed recent and future
developments in tilapia culture. Attended by fishery scientists from
around the world, the conference was the most important meeting held in
western Africa and made important contributions to the sustainable
development of aquaculture in Africa and other countries. Available in
English and French, with translation by Catherine Lhomme-Binudin.

-   UNEP World Conservation Monitoring Centre. ***GEO3 Endangered
    Animals Snapshot***. <http://valhalla.unep-wcmc.org/isdb/geo3.cfm>

This online database lists endangered species by geographical location
(region and country) and animal type. Species are further divided into
critically endangered, endangered, and vulnerable categories.
Information available about each species includes its native range, when
it was listed as an endangered species, and links to resources about the
specific animal.

[^1]: Source: Pullin, *Third World Aquaculture and the Environment*
    (1989), as cited by Baluyut (1989).