Finfish Breeding and Hatchery Management (2+1)

Unit 14 - Breeding of groupers

14.1. Distribution and importance

• Groupers belong to the family Serranidae and Order Perciformes.
• Important species are Epinephelus tauvina and E. malabaricus.
• They are distributed in the Indo-Pacific region.
• E. tauvina is found mainly in the east coast of India.
• Can be cultured in brackish water and marine waters.
• They are demersal, highly carnivorous and highly predatory, cannibalistic when food is scarce.
• Both the species have been successfully induced bred in South-Asian countries particularly Singapore and Thailand.
• An important foodfish, commands high price (up to Rs. 400/- per kg)
• Suitable for culture in net cages as well as in ponds.
• Grows to 500- 800 g in 6 months, maximum size recorded is 100 cm.
• Spends the growing phase in shallow brackishwater, estuaries and rivers.

Identifying characters

• Elongate and compressed body, with a deep caudal peduncle.
• Head is pointed with a concave dorsal profile, becoming convex in front of the dorsal fin.
• Mouth large, slightly oblique and the lower edge of the pre-opercle is serrated, with a strong spine.
• Adults are greenish or bluish; scales with black spots.
• Eyes glow.

Food and feeding

• Highly predatory, feeding on small fish and crustaceans.
• Juveniles are omnivorous.
• Fry feed on zooplankton, while fingerlings prefer small crustaceans, worms, mollusks, etc.

Breeding season

• Spawning season is November – May.
• It migrates to deeper waters for breeding.
• Is a protogynous hermaphrodite (functions first as female and then turns to male after spawning, i.e. natural sex-reversal).
• Fish in the weight range 2 – 3.5 kg are females, whereas those in the size range 3.5 – 5.0 kg are males.
• Three to four year-old fish show 1:1 (M:F) sex ratio.
• Males mature at 25 cm length.

Grouper