Aquaculture Of Grouper (1)

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AQUACULTURE OF GROUPER
GROUPER IN GENERAL
Found mostly on coral reefs, sometimes in estuaries, or rocky areas in the subtropical/tropical areas. (<100)
Live long lives (>40), slow to grow, gets large
Eats fish, crustaceans, cephalopods from lairs
Unless spawning lives alone on a stretch of reef.
Are sequential hermaphrodites
Prized for its meat.
WATER SWEET WATER
Prefers=>
Tropical to Sub-tropical climes are preferred
Temperature: 28-30C
Salinity: 34.9 psu max
Well aerated water
Not much disturbance
LIFE CYCLE
Spawn between May and August in a mass school after a migration
Larvae hatch within a few hours (plankton)
Move in ward to shallower more sheltered waters
Grows into a fingerling ( few cm- a finger length)
As they grow they go into deeper waters
Become a juvenile (female or immature male)
Eventually turns into a male
GROUPER FARMING
Most developed in Asia. (Taiwan, China, Indonesia)
Grouper grows very fast in higher temps.
FCR=1.67:1 (Dried fish formula)
6.00:1 (Trash Fish)
Hand fed (pan/two-four scoops scoops)
Robust in over crowded cages
Cost $1.27 per kg (fish formula)
$0.37 per kg (Trash Fish)
TROUBLE SHOOTING
(DISADVANTAGES)
Aquaculture of grouper is not well organized
Still relies on seed caught out in ocean
Most of wild seed dies before and during farming 60,000t (fry, fingerling,
juveniles)= 23,000t food
Contributes to species crash
ADVANCEMENTS
Grouper hatcheries have recently been made to help meet demand.
Can now produce over 100-200,000 hatched seed per year.
Two-thirds of Taiwan production of grouper is from hatcheries
Survival rate of fry is still low 2-10%
Twenty thousand broodstock were required for the production of 20 million
fingerling
GETTING KINKY
Eggs come from low density brood ponds (Water is pumped from the coast)
Aerated with paddle wheels
Brood stock is fed on trash fish.
One female to two males. (replaced yearly)
Spawning last days to months
Eggs collected by a current and skimming net. (eggs= $166 per kg)
24h after spawning eggs hatch
JUST KEEP FLOATING
(HATCHERY)
Eggs held in Sea water that is being constantly aerated with out to much water
disruption
Has mechanical, biological, and UV sterilizers attached.
Is temperature regulated. (28-30C)
Larvae open mouths on day three then fed supply of phytoplankton, oyster
eggs, and small trochophore larvae till day forty then they eat artemias.
Kept at three larvae per liter.
Kept for forty days till Fingerlings (1 Fingerling = $1.10)
WONDER WERE NEXT
(NURSERY-GROW OUT)
Raised in circular tanks till 10g.
Natural light
Fed fishmeal pellets (high protein)
Lasts 30 days
Then to grow out tanks
Commercial grouper in Taiwan are 30cm and 600g or 1kg
Takes different species different times
E. lanceolatus= 6 months
E. Malabaricus= 12 months
E. coioides= 12-15 months
Once this size they go to culture cages
WON’T LIVE TO BE OLD
(BEFORE SUSHI)
Once big enough the juveniles are placed in nets placed at the ocean end of
an estuary or in the open ocean.
Low mortality rate. (80% survive)
Usually sold alive
Nets are emptied then cleaned every six months
TAXONOMY OF THE HARVEST
Epinephelus coioides= Orange-spotted grouper
Epinephelus malabaricus= Malabar grouper
Epinephelus lanceolatus= Giant grouper
Epinephelus Tauvina= Greasy grouper
Epinephelus fuscoguttatus= Brown-marbled grouper
Epinephelus Akaara= Honkong grouper
Epinephelus awoara= Yellow grouper
Epinephelus quoyanus= Longfin grouper
Epinephelus trimaculatus= Threespot grouper
Cromileptes altivelis= Humpback grouper
Plectropomus leopardus= Leopard coral grouper
PRICE RANGES
Orange-spotted grouper= $8–$11 per kg
Malabar grouper= $8-$11 per kg
Giant grouper= $15 per kg
Greasy grouper= $7-$12 per kg
Brown-marbled grouper= $15–$20 per kg
Honkong grouper= $30–$40 per kg
Yellow grouper= $29.90 per kg
Longfin grouper= $24.99 per kg
Threespot grouper= $13.89 per kg
Humpback grouper= $80–95 per kg
Leopard coral grouper= $30–$40 per kg
WHERE THEY SELL AND WHY
Japan
China
Taiwan
Thailand
Malaysia
Indonesia
Philippines
Hong Kong
Are one of the most used species
in the world.
Is a multi-billion dollar business with
employees and all.
WORKS CITED
Pierre, Gaillard, et al., Grouper aquaculture: Asian success and
Mediterranean trials., 2007. John Wiley & Sons, Ltd.
Sim, Phillips, et al., A Practical Guide to Feeds and
Feed Management for Cultured
Groupers., No. 2005–02, Asia-Pacific Marine Finfish Aquaculture
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