CMFRI breakthrough revives hope for mangrove clam restoration

Kochi (Kerala), Feb 9 (IANS) In a significant boost to efforts aimed at restoring a rapidly declining estuarine resource, the ICAR–Central Marine Fisheries Research Institute (CMFRI) has successfully achieved induced breeding of the mangrove clam (Geloina erosa) under captive conditions.

The scientific breakthrough is expected to mark a major milestone in developing community-managed estuarine aquaculture models that are closely integrated with mangrove conservation.

Mangrove clams, commonly known as mud clams, are an ecologically important but dwindling bivalve species distributed across mangrove and estuarine ecosystems in South and Southeast Asia.

Despite their declining availability, they continue to be a valued local delicacy in several parts of India, particularly in northern Kerala, where the species is popularly known as ‘Kandal Kakka’.

The clam typically inhabits organic-rich muddy substrates in intertidal mangrove zones.

Scientists from the CMFRI’s Mariculture Division successfully induced spawning in captive broodstock and completed the entire embryonic and larval development cycle under controlled conditions.

The team recorded successful spat settlement from the 18th day after spawning, demonstrating the feasibility of producing viable seeds in a hatchery environment.

The achievement represents one of the very few documented global instances of induced breeding, larval rearing, and spat production of the mangrove clam.

Building on this success, CMFRI scientists are now working to standardise larval rearing and nursery management protocols to improve survival rates and enable large-scale seed production.

According to the researchers, the development of robust hatchery technology, coupled with grow-out farming in suitable estuarine systems, could pave the way for low-input, environmentally sustainable aquaculture.

They point out that hatchery-produced seeds can be used for ranching in degraded or critical mangrove ecosystems, thereby simultaneously supporting clam stock enhancement and mangrove restoration.

The breakthrough is expected to open new avenues for sustainable livelihoods and nutritional security for mangrove-dependent communities, particularly along the Kerala coast.

Farming initiatives based on hatchery-produced seeds could help restore depleted natural stocks, reduce pressure on wild populations, and provide stable income opportunities for coastal households.

Across India — especially along the east coast and in island regions, wild mangrove clam stocks have declined steadily due to indiscriminate harvesting, habitat degradation, pollution and coastal development.

The absence of scientific stock assessments, size regulations and seasonal harvesting controls has further worsened the depletion, leading to visible reductions in both abundance and shell size.

One of the world’s largest mud clams, capable of reaching shell widths of up to 10 cm, the species plays a crucial ecological role by recycling nutrients, stabilising sediments and strengthening mangrove ecosystems, while also underpinning food security and livelihoods in coastal regions.

–IANS

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