Unit 5: Aquaculture

tuna aquaculture method

...

Economic sustainability

Aquaculture must be a viable business with good long-term prospects.

Social and community sustainability

Aquaculture must be socially responsible and contribute to community well-being.

Environmental sustainability

Aquaculture should not create significant disruption to the ecosystem, or cause the loss of biodiversity or substantial pollution impact.

sustainable aquaculture

Aquaculture that causes less short and long term damage to the environment, economy, and local community Sustainable aquaculture is a dynamic concept and the sustainability of an aquaculture system will vary with species, location, societal norms, and the state of knowledge and technology.

Economic: list of requirements from powerpoint

Clean Water: reduce mortality rates caused by disease and accumulations of toxins; not as much of a problem in extensive; bigger problem in intensive, need to have constant running water

Economic: list of requirements from PowerPoint

Disease management: high density populations encourage growth and spread of parasites; requires use of antibiotics , fungicides, pesticides

Economic: list of requirements from powerpoint

Feed availability: extensive - food provided naturally; intensive food has to be added in order to maximize growth rates (speed of growth of populations in terms of number or size of individual fish)

Economic: list of requirements from powerpoint

Feed efficiency: extensive - natural; intensive requires a strategy to afford to overfeed to avoid waste and pollution (excessive feed may foul the water)

Environmental Sustainability and Impacts: Factors that must be addressed:

Habitat destruction Overexploitation of feed stocks Pollution Introduction of exotic species (not native to a particular location e.g. lionfish) Spread of disease Competition for resources

Economic: list of requirements from PowerPoint

Location: extensive require an area of natural water that is accessible and suitable for the species; must have appropriate food and water temperatures; intensive require more support and are very costly

growth rate

Rate of increase or decrease of a population

Minimizing negative effects:

Reducing pollution Sustainably using resources Preventing escape Conserving habitat Minimizing social impacts

Grouper aquaculture method

Some use brood fish to produce the juveniles Others collect eggs or fry (larva) from the wild Producing fry from brood stock doesn't have negative impact on wild populations Broodstock are a group of mature individuals used in aquaculture for breeding purposes. It can be a population of animals maintained in captivity as a source of replacement for, or enhancement of, seed and fry numbers Natural: nocturnal, between temperatures of 27 and 28 C; fertilized eggs remove from tank so adults don't eat them Induced: inject male and female broodstock with hormone called hCG; placed in a tank at 28-28.5 C Fertilized eggs placed into tanks; become fry; reach fingerling size; transferred again Once reach 6 cm in length, move outdoors; harvested after about 7 months of growing Practical Activity: In small groups, plan an experiment for the culture of tilapia in a range of temperatures

exotic species

Species that are carried to a new location by people

Economic: list of requirements from PowerPoint

Stock: brood stock, buying fertilized eggs, removing juvenile from the wild; breeding stock preferable to removing juveniles before they reproduce in the wild

giant clam aquaculture method

Three main techniques are employed in induced spawning of giant clams. The first method is based on an intragonadal injection of serotonin, a natural neuro-transmitter in giant clams. In a second method, the gonads from a ripe individual are excised, blended and added to the tank in which the broodstock are held.

aquaculture

the rearing of aquatic animals or the cultivation of aquatic plants for food.

intensive aquaculture

aquaculture that uses intensive methods such as high stocking densities and artificial feeding to maximize production

extensive aquaculture

aquaculture that uses little technology, low stocking densities and no artificial feeding (PPT to reinforce)

shrimp aquaculture method

breed in tanks, fed phyto, zoo and brine shrimp; requires pesticides and antibiotic Nursery: post larval move to long shallow tanks with flowing water Grow out ponds after reach juvenile stage 2 main species: pacific white shrimp, tiger prawn Breeding and hatcheries: collection of shrimp, post larvae ,causes pressure on wild stock - negative impact Method for Farming Shrimp: Extensive: low density; trapped in ditches, feed on naturally occurring food; water is refreshed by the sea Semi-intensive: don't rely on tides, separated from coastal waters, costs are higher; pond renovation and upkeep, supplement food Intensive: fully automated; bred on site; high density; system of pumps for aeration, filtration; high production costs; antibiotics and pesticides