Grouper Aquaculture Flashcards
What are the advantages of grouper aquaculter?
- High consumer demand.
- Resilient fish
- Responds well to aquaculture
- Helped to reduced overfishing of wild stocks
What are the disadvantes to grouper aquaculter?
They are slow growing
How may grouper aquaculter begin?
Adults may be taken from the environment for a brood stock
What is a brood stock
a population of animals maintained in captivity as a source of replacement for, or enhancement of, seed and fry numbers
What is the advantage of having a brood stock to produce juveniles?
It is more sustainable
What temperature water are brood tanks filled with?
seawater at 27oC-28oC (spawning temperature)
When does grouper spawning happen?
During a full moon
Why are eggs removed when produced?
To avoid predation from parents
What intensive method can be used in grouper aquaculture?
will inject hCG hormone (human chorionic gonadotropin) to induce spawning.
Explain the larval stage of grouper aquaculture
- The fertilised eggs are put in tanks (600000/m3)
- The water is aerated to maintain oxygen levels
- After hatching the yolk sac fry are removed to larval tanks
- The larvae are fed intensively for 7 days as they grow to about 2-3cm in length
Explain the fingerlings stage of grouper aquaculture
- Placed in indoor or outdoor tanks.
- Fed intensively until 6cm long
- Fresh, filtered, oxygen rich water in regular supply
- Vaccines and antibiotics used to prevent disease
Explain the juvenile stage of grouper aquaculture
- 6+cm are moved to outdoor tanks, ponds or cages.
- Fed twice a day (intensive)
- Sometimes tilapia are placed in the cages to breed and produce fry as a food source for the grouper
- Juvenile Grouper start as females and some change to males (usually between 4-6 years)
- Juveniles are fed high protein and high cholesterol diets (shellfish, squid, sardines and mackerel)
