Blue Swimmer Crab (Portunus reticulatus)

Why in News?

Recently, Indian Council of Agricultural Research – Central Institute of Brackish water Aquaculture (ICAR‑CIBA), Chennai successfully demonstrated India’s first Blue Swimmer Crab farming technology.

• Common Names – Blue swimmer crab, blue manna crab, flower crab.
• Scientific Name – Portunus reticulatus.
• Family – Portunidae (brachyuran crabs).
• Appearance – Hue of blue colour, Flat, disc‑shaped hind legs adapted as paddles for swimming; nine spikes along carapace near eyes.

• Distribution – Widely found in Indo‑Pacific (Indonesia, Vietnam, Philippines, China, Japan, Malaysia, Australia, India, Singapore).
• In India, dominant fisheries at Palk Bay and Gulf of Mannar.
• Diet – Bivalves, fish, and macroalgae during high tide.

Key Characteristics

• Stays in burrows under sand/mud during daytime and winter, has high tolerance to ammonium/ammonia.
• Cannibalism – Lower compared to other brackishwater crabs (suitable for farming).

Aquaculture Technology Package (ICAR‑CIBA)

• Seed Production – Standardized hatchery protocols, short production cycle comparable to shrimp farming.
• Feed – Formulated pelleted feed branded as BSCrabPlus.
• Farming Practices – Nursery rearing and grow‑out culture at 1 crab/m² stocking density.
• Outcome – Marketable crabs harvested in 105 days; revenue handed to beneficiaries under Scheduled Caste Sub‑Plan.

Reference

PIB | Blue swimmer crab