Giant Clam Conservation in Coral Reef Ecosystems

Giant clams (Tridacninae) are among the largest bivalves inhabiting Indo-Pacific coral reefs, where they perform critical ecological functions, including reef building, nutrient cycling and habitat provision. Their symbiotic partnership with photosynthetic algae enhances reef productivity and supports biodiversity. However, overharvesting for meat, shells and the aquarium trade, coupled with habitat degradation, ocean warming and acidification, has driven several species to local extinction and prompted international protection measures. Conservation approaches span in situ measures—such as marine protected areas, restocking of depleted populations and management of sedimentation and turbidity—to ex situ solutions, including selective breeding and large-scale aquaculture. Recent advances in our understanding of giant clam biomineralisation, physiological responses to multiple stressors and patterns of larval dispersal have begun to inform more targeted interventions. Holistic strategies that integrate physiological research, spatial modelling and community engagement promise to bolster recovery of these flagship species and the coral reef systems they sustain.

Research from Nature Portfolio

Recent studies have characterised how environmental gradients influence the shell formation and chemical composition of giant clams. Analyses of aragonitic shells from high-turbidity versus low-turbidity reefs revealed striking differences in crystal orientation and element-to-calcium ratios, suggesting that clams adjust their biomineralisation pathways in response to suspended sediments. These findings imply that turbid reefs, often overlooked as marginal habitats, may serve as resilience hotspots, with clams exhibiting greater trophic flexibility by shifting between autotrophic and heterotrophic nutrition. Such mechanistic insights into shell structure and physiology are critical for predicting clam survival under future scenarios of increased sediment load and ocean acidification, thereby guiding site selection for conservation and restocking efforts.

Giant Clam Conservation in Coral Reef Ecosystems publication trend

The graph below shows the total number of articles in giant clam conservation in coral reef ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Aragonite: A crystalline form of calcium carbonate that composes giant clam shells and coral skeletons.

Biomineralization: The physiological process by which organisms produce mineralised structures, such as bivalve shells.

Holobiont: The functional unit comprising a host organism and its associated microbial and algal symbionts.

Turbidity: The measure of water clarity determined by the concentration of suspended particles, affecting light penetration.

Symbiosis: A mutually beneficial association between organisms; in giant clams, this refers to the relationship with photosynthetic algae (zooxanthellae).

References

1. Crystallographic and geochemical responses of giant clams on turbid reefs. Scientific Reports (2025).
2. The role of aquaculture in the international trade of giant clams (Tridacninae) for the aquarium industry (2001–2019). Aquaculture (2024).
3. Recruitment constraints in Singapore's fluted giant clam (Tridacna squamosa) population—A dispersal model approach. PLOS ONE (2013).
4. Best Management Strategies for Sustainable Giant Clam Fishery in French Polynesia Islands: Answers from a Spatial Modeling Approach. PLOS ONE (2013).
5. Conserving threatened species during rapid environmental change: using biological responses to inform management strategies of giant clams. Conservation Physiology (2021).