Aquaculture: Definition and Activities

Aquaculture Basics

• Aquaculture involves cultivating aquatic organisms like fish, mollusks, crustaceans, and plants
• Aquaculture enhances production through interventions such as regular stocking, feeding, and predator protection
• A key aspect is ownership of the cultivated stock, distinguishing aquaculture from capture fisheries

Aquaculture Activities

• The following activities are part of aquaculture
• Rearing fry, spat, and post-larvae in hatcheries
• Stocking various water bodies to produce marketable aquatic organisms
• Culturing in private tidal ponds like Indonesian Tambaks
• Rearing mollusks to market size
• Stocked fish culture in paddy fields
• Harvesting of planted/suspended seaweed is aquaculture
• Valliculture, is aquaculture in coastal lagoons

Origin of Aquaculture and Agriculture

• Agriculture started about 10,000 years ago in the Middle East
• The start of growing wheat and barley led to farming cereal crops
• Rice cultivation began in Asia approximately 7,000 years ago
• Sorghum and millet were first cultivated in Africa
• Maize was first developed in America
• Aquaculture's origins are later than agriculture's
• Common carp culture began in China a few centuries BC.
• The first aquaculture textbook was written around 500 BC by Fan Lei, a Chinese politician
• Africa, America, and Australia only adopted aquaculture in recent centuries
• Aquaculture's late start is due to humans being terrestrial, making it harder to understand aquatic environments

Aquatic Environmental Factors

• The following aquatic parameters affect aquatic organisms
• Low oxygen solubility
• High carbon dioxide solubility
• Hydrogen ion concentration (pH)
• Salinity
• Buffering capacity
• Dissolved nutrients
• Toxic nitrogenous wastes
• Turbidity
• Heavy metals/toxic substances
• Photo and zooplankton concentration
• Current velocity
• Terrestrial humans struggle to fully grasp these factors, slowing aquaculture's progress compared to land based food production

Genetic Selection

• Aquaculture began later, the genetic selection in farmed fish is less advanced than in agriculture
• Modern agriculture relies on organisms greatly changed from their wild ancestors over thousands of years
• Aquaculture predominantly uses wild plants and animals
• Only a few aquatic species are domesticated

Examples of Domesticated Fish

• Common carp
• Atlantic salmon
• Rainbow trout
• Tilapia species
• Channel catfish
• A lot of aquaculture relies on wild brood stock because their production cycle is yet to be fully closed

World Aquaculture (2010)

• Aquaculture plays a growing role in protein production Production in 2009 was 55.7 million tons, valued at USD 105.3 billion
• Aquaculture expanded at an annual rate of 6.1% from 2001 to 2009

Aquaculture Numbers

• The per capita fish supply from aquaculture went from 0.7 kg in 1970 to 7.8 kg in 2008
• From 1750 to 2009, aquaculture output rose from 1 to 55.7 million metric tons
• Aquaculture's growth is triple that of meat production
• With capture fish production stagnant since the mid-1980s at 90 MMT, future fish production must rely on aquaculture
• Plant production in aquaculture reached 17.3 million MT in 2009, worth USD 4.8 billion

Aquaculture Production by Region

• Asia accounted for 88.8% (quantity) and 78.7% (value) of total aquaculture production in 2008
• China makes up 62.3% (quantity) and 51.4% (value) of global production
• Asia excluding China makes up 26.10% of global fish production via aquaculture
• The top 15 producers contributed 92.4% of world aquaculture production
• Developing nations produced 48.62 million tons of food fish, valued at USD 84.03 billion

Top Aquaculture Producers (2009)

• China: 34.78
• India: 3.79
• Vietnam: 2.66
• Indonesia: 1.73
• Thailand: 1.39

Aquaculture Production by Environment (2009)

• Freshwater environments dominate aquaculture production
• Freshwater accounted for 60.61 (quantity) and 56.0% (value)
• Seawater accounted for 31.75% (quantity) and 30.7% (value)
• Brackish water accounted for 7.60% (quantity) and 13.3% (value)

Species in Aquaculture

• Carps are the most commonly cultured species, at 40% of production by volume
• Other significant groups include shellfish, tilapias, shrimps, prawns, and salmons

Percentage Contribution by Species

• Carps: 39.9%
• Tilapia and other cichlids: 5.6%
• Miscellaneous freshwater fish: 9.5%
• Salmons, trouts, smelts: 4.41%
• Shrimps and prawns: 6.27%
• Oysters: 7.7%
• Marine mussels: 3.2%
• Scallops (Pecten): 2.84%
• Clams, cockles, arkshells: 7.96%
• Miscellaneous marine molluscs: 1.66%

Freshwater Resources for Aquaculture

• Freshwaters are essential for human survival and fish farming by dividing into
• Surface waters
• Ground water
• Ice and glaciers
• Soil moisture

Surface water Subdivisions

• Surface waters can be sub-divided into
• Rivers/streams
• Lakes
• Ponds/tanks
• Wetlands

Top 10 Countries with Freshwater Resources

• Brazil has 14.9%
• Russia has 8.1%
• Canada has 6.0%
• United States has 5.6%
• Indonesia has 5.1%
• China has 5.1%
• Columbia has 3.9%
• Peru has 3.5%
• India has 3.5%
• Congo has 2.3%
• The rest of the world has 40.0%

Indian Freshwater Resources

• Ponds and tanks are best for culture, pen and cage culture can be undertaken in Lakes and Reservoirs
• India has different freshwater resources that can be utilized for fish culture

Types of Water Bodies in India

• Ponds and tanks cover 2.25 million ha.
• Lakes and Reservoirs cover 2.09 million ha.
• Bheels and wetlands cover 1.30 million ha.
• Paddy fields cover 2.30 million ha.
• Irrigation canals cover 0.12 million ha.
• 45% of India's ponds and tanks are used for fish culture leaving great potential for horizontal expansion

Biological Resources (India)

• India has great fish biodiversity, including specific species that can be used for fish culture

Carps in India

• India is a carp country
• Freshwater farming relies on carps
• The main species cultivated are Catla, Rohu, and Mrigal
• Composite fish culture includes silver carp, grass carp and common carp
• There is a wide range of carp seed production and culture technologies

Air-Breathing Fish in India

• Giant, striped, and spotted murrel, Magar, Singhi, and Climbing Perch are available for culture
• Air-breathing fish are the second most commonly cultured fin fish in freshwater
• They withstand poor water
• Can be grown in marshes and derelict water, where it is unsuitable for carp culture

Crustaceans in India

• Giant freshwater prawn and Indian River prawn are of crustaceans suitable for culture
• Can be polycultured with carps that are fast-growing and well priced for export
• Monoculture gives yield of 800-1000 kg/ha/year

Molluscs in India

• Freshwater mussels are used for freshwater pearl production

Cold-water Fish in India

• Mahseers and exotic trouts are available species for cold-water fish culture
• The Species Mahseers suitable for culture are Tor putitora; T. torT. khudree, T. mosal and T. malabaricus
• The snow trout and minor carps are also species that work
• Exotic cold-water fish includes Salmo gairdneri, S. trutta fario and Salvelinus fontnualis
• The tench is also a fish that is suitable

Status of Freshwater Aquaculture in India

• Rapid expansion of freshwater aquaculture occurs in India, especially Andhra Pradesh and West Bengal
• As in China and other parts of Asia, carps are a main group of fish

Freshwater Aquaculture Stats

• Freshwater aquaculture, accounts for 70% of the total Inland production
• Aquaculture grows at 5.6% per annum
• Carps contribute to 90% of freashwater aquaculture
• R&D and extension have enhanced aquaculture productivity in India, but the potential is yet to be reached

Systems for Increasing Fish Production

• The following are systems with increasing fish production in India
• Composite fish culture: 4-6 tons/ha/yr
• Intensive culture: 10-15 tons/ha/yr
• Clarias culture: 3-5 tons/ha/yr
• Sewage-fed fish culture: 3-5 tons/ha/yr
• Integrated fish culture: 3-5 tons/ha/yr
• Pen culture: 1-2 tons/ha/yr
• Running water culture: 20-50 kg/m^3
• Cages: 10-15 kg/m^3

Nursery, Rearing and Grow-out Ponds

• Nursery ponds: Spawn are reared to fry stage. This takes about 15-20 days
• Rearing ponds: Fry are grown to fingerling size. This takes about 2-3 months
• Grow-out ponds: Fingerlings are stocked and grown to harvestable size. This takes about 10-12 months.
• Aquaculture is the farming of aquatic organism
• Farming implies intervention in rearing for enchanced production
• Pre-stocking, stocking and post-stocking management are ways of enhancing pond production

Pre-Stocking Management

• Ensure optimum environment for fish growth by making sure that it is free of predators, aquatic weeds or weed fish
• Ensure that it has optimum water quality parameters and provide sufficient natural food in semi-intensive culture systems
• Steps are similar in nursery, rearing and grow-out ponds
• Additional step in nursery ponds is eradication of aquatic insects that predate on spawn and fry

Drainable Pond Management

• Draining and drying
• Ploughing
• Liming
• Filling with water
• Fertilization

Management of Un-drainable water

• Control of aquatic weeds
• Eradication of weed fish and predatory fish and animals

Additional Nursery Pond Managment

• Eradication of aquatic insects

Draining, Drying, Ploughing and Liming

• Drying the pond helps promote Oxidation of organic matter
• It also degasses toxic matter eg ammonia and hydrogen sulphide
• Kills pathogenic micro organisms
• Kills predatory, weed fish and unwanted aquatic plants
• 7-10 days of drying allows cracks in clayey soil or just until the soil can support a person and foot prints do not form

Importance of Ploughing

• The ponds should be ploughed using wooden ploughs or power tillers or tractors
• Ploughing helps mix up the soil, leading to oxidation of organic matter and degassing toxic gases
• Ploughing also help with Mineralization of nutrients

Importance of Liming

• Key factors of fish ponds that depend on soil qualities are
  • Texture
  • Water retention
  • pH
  • Organic carbon
  • Available nitrogen
  • Available phosphorous
• Mineralization of organic matter and nutrient release affect the quality of pond soil, thus enhancing productivity

Properties of Soil pH

• Soil pH corrected with desirable pH being 6.5 – 7.00
• Corrects soil pH and can be performed by using
  • Agricultural lime or calcite
  • Dolomite
  • Calcium hydroxide/slaked line
  • Calcium oxide/quicklime
• Variety of lime depends on its effectiveness and soil pH
• After application, the lime should be mixed with the top soil with light ploughing.
• Quick lime is preferred for applying to soil and calcite agricultural lime for application to water after stocking of the ponds

What Liming Helps in

• Correcting soil pH
• Mineralization of organic matter
• Releasing soil sound phosphorous to water
• Disinfection of the pond bottom

Pond Fertilization

• Fry and fingerlings feed on zooplankton
• Sustained zooplankton production in ponds depends on good phytoplankton and bacterial base
• Maintained through adequate availability of nutrients such as Nitrogen, Phosphorous carbon and micronutrients
• These nutrients in ponds will be inadequate in natural water
• Must be externally added to sustain good plankton growth
• Nutrients are added to water through organic manures and inorganic fertilizers.

Importance of Organic Manures

• Organic manures are rich in carbon and contain nutrients such as N and P
• Decompose slowly and release the nutrients slowly
• Promote the growth of zooplankton through saprophytic food chain
• Promote sustained growth of phytoplankton and zooplankton for longer periods of time
• There are types of manures e.g cow dung, poultry litter, pig dung, horse dung that can be used to fertilize fish ponds.
• Common manures used in fish ponds are cow dung and poultry manure
• Raw cow dung is applied at 5-10 tons/ha 15 days before stocking.
• Applied in phases ( 2/3 of the amount as basal dose with 2nd dose following it a week later)
• Poultry manure is 2-3 times richer than cow dung, apply half the dose should it be what is being used

Inorganic Fertilizers

• Concentrated nutrients such as N and P
• N -> Urea or ammonium sulphate
• P -> single or triple super phosphate
• Promote production of phytoplankton which will stimulate zooplankton production
• When used incautiously can cause undesirable Blue Green Algae (BGA)
• Organic and inorganic fertilizers promote phytoplankton which will sustain for a longer period of time.

Control of Aquatic Weeds

• Large earthen ponds can be usually infested by submerged weeds
• Weeds can cause several problems for fish ponds
• Aquaric Weeds Compete for nutrients with phytoplankton (thereby reducing natural productivity)
• It Prevents light penetration (suppress production of phytoplankton), can cause oxygen super saturation and hinders fish
• Aquatic weeds be controlled by mechanical, chemical and biological means
• The method selected depends on Pond size, Cost and time

Eradication of Predatory and Weed Fish

• Predatory and weed fish severely affect survival of fish primarily in nursery and rearing ponds due to space and the amount of food
• predatory fish commonly are murrels (Snakeheads), wallago attu,. etc
• weed fish include Putinus, Barbas Danio. etc
• Predatory and weed fish must be eradicated prior to stocking of catps

Effective Eradication

• Must be effective at low dose
• Not injurious to people and animals
• Gets detoxified to not affect the fish being suitable for consumers
• Easily available and economical
• Chemicals, pesticides and plant origin work better

Piscicides

• Derris root powder
• Rotenone is the active ingredient
• Has Lethal result if mixed with organisms and water or sunny days
• Mahua oilcake
• Toxicity reduced after weeks
• Other common toxicants are Tea seed cake , tamarind seed husk
• Jaggery works too

Stocking and Post-Stocking Management

• Used on a need to be basis in Nursery and rearing
• Acclimatize water prevents low water that cuases stress
• Monoculture is used best
• Grow-out culture of carnivores is in line with monoculture

Proper Stocking

• Occurs during cool hours
• Supplementary (natural food) will be sufficenent in right conditions
• Commonly, supplementary feeds such as mixture of rice bran or wheat brawn mixed with oil cakes iin a 1:1 ratio

Feeding Rates

• rates vary
• Spawns can be fed at 8-10%
• Fry at 6-8%
• Gradually harvest at a of 2.3 %

Water Quality Management

• Good growth and production of fish not only depends on availability of good quality feed but also on the water of choice .
• The physico-chemical propertiies is highly recommended
• High stocking densities are followed
• Water quality tends ot deteriorate under growth and biomass increase
• Oxygen is improtant

Fish Culture Methods

• Fish need to be carefully cultured via
  • The nursery phase
  • Rearing phase
  • Grow-out phase
  • Each steps needs to be treated

Nursery Phase

• The nursery phase has carps spawn for approximately 15 days
• All The steps are :Drying , eradication and other steps for water control
• Additional un-dranable ponds include Aquatic Weed control, eradication of predators, etc

Pond Ferilization

• Nursey are feritilized with manuries to promote both phyto and zooplankton

Insect Control

• Insects or larvae can kills fish or bodies there need to not compete woth poor surivcal
• Soap is usually used at 56%

Catfish

• Needs to be placed with other organisms
• Density rates

Transporting Of Fry And Fingerlings

• Use sealable bags with oxygne
• Condition 24-48 hours
• Use protection for damage
• Also Use Ice to stabilize metbolic to rate

Prestocking

• Weeds need to be cleared
• Apply Lime
• Then Manure
• Then Fertlize
• This order is key

India is Key for Fish Farming

• Its important to always improve average yield in farm
• Weeds need to be taken control and care
• 30-4 is good with care </