Source: DD News
Subject: Environment
Context: The ICAR–Central Marine Fisheries Research Institute (CMFRI) has successfully achieved induced breeding of the mangrove clam under captive conditions, a rare global scientific feat.
About Mangrove clam (Geloina erosa):
What it is?
- An ecologically important bivalve (mud/mangrove clam) found in mangrove and estuarine ecosystems of South and Southeast Asia; locally called “Kandal Kakka” in northern Kerala.
Scientific name: Geloina erosa (also placed under the genus Polymesoda in some literature).
Habitat:
- Organic-rich muddy substrates of intertidal mangrove zones.
- Tolerates a wide salinity range (brackish to near-freshwater).
- Deep-burrowing, semi-infaunal species; adults often landward, juveniles more tide-independent.
Key characteristics:
- Large-sized mud clam: One of the world’s largest mangrove clams, reaching ~10 cm shell width, making it valuable both ecologically and as a food resource.
- Efficient filter feeder: Filters suspended particles and plankton from water, recycling nutrients and improving estuarine water quality.
- Distinct gonadal identification: Sexes are identified by gonad colour and structure, not external organs, aiding reproductive studies and broodstock selection.
- Ecosystem stabiliser: Burrowing behaviour stabilises sediments, enhances nutrient cycling and strengthens overall mangrove ecosystem resilience.
Method used to restore / conserve:
- Induced breeding in hatchery: CMFRI achieved controlled spawning under captive conditions, overcoming dependence on wild seed collection.
- Complete life-cycle closure: Successful rearing from embryo to larva to spat (from ~18th day) proves hatchery-scale feasibility.
- Hatchery seed production for multiple uses:
- Grow-out farming: Enables estuarine aquaculture with minimal external inputs.
- Mangrove ranching: Seeds can be released into degraded mangroves to restore natural populations.
- Stock enhancement: Reduces harvesting pressure on wild clam beds by replenishing natural stocks.
Significance:
- Requires minimal feed and infrastructure, making it environment-friendly and climate-resilient.
- Integrates aquaculture with ecosystem regeneration, reinforcing mangrove–benthic linkages.
- Provides an affordable high-protein seafood source for coastal and estuarine communities.
