Unit 12Aquaculture

• The FOOD CHAIN in a freshwater pond

• WATER QUALITY

• Production systems

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Aquaculture Defined

The management of the Earth’s water surface to INCREASE the harvest of usable plant and animal products

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The Aquatic Environment

• The salinity gradient

• The aquatic food chain– Sunlight.– Green plants and algae.– Plants are eaten by the fish.– Fish are eaten by larger fish and animals.

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A Little Biology• Shellfish

– are aquatic animals with a shell.– include clams, mussels, oysters.

• Crustaceans– are aquatic organisms with

EXOSKELETONS.– MOLT (replace their outer shells as they grow).– include saltwater lobsters, crawfish, crabs,

shrimps, prawns.

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Testing Water QualityTest for

• dissolved oxygen (amount of oxygen in the water).

• pH (the alkalinity or acidity of the water).

• water hardness (amount of calcium in the water).

• turbidity (amount of suspended matter in the water).

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Testing Water Quality (continued)

• temperature.

• ammonia/nitrite/nitrate levels.

• toxins.

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Selection of Aquaculture Crops

• Trout and salmonids

• Catfish

• Clams, crabs, and oysters

• Shrimp and prawn

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Production Systems

• Open ponds, rivers, and bays—stocked

with natural or cultured young

• Caged culture—floating-pen cages in

natural waters

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