How do mollusks contribute to food chains and ecosystems?

Mollusks play vital roles in ecosystems and food chains as primary consumers, predators, and scavengers across marine, freshwater, and terrestrial habitats.123

Contributions to Ecosystems and Food Chains

• Primary Consumption and Organic Turnover: Many mollusks, particularly bivalves, are essential filter feeders that consume phytoplankton, bacteria, and plant detritus. By filtering large volumes of water, they contribute significantly to organic turnover in aquatic environments.4561
• Trophic Interactions: Mollusks serve as a critical food source for a wide variety of predators, including crustaceans, starfish, and other mollusks. Conversely, some gastropods and specialized deep-sea bivalves act as predators, while others function as scavengers that process dead plant or animal matter.462
• Bioerosion: Certain bivalves, such as shipworms and piddocks, are important agents of bioerosion, breaking down wood and rock, which influences habitat structure.5

Ecological Impact

While many species are integral to healthy ecosystems, some, such as the zebra mussel, are invasive. These species can disrupt established food webs and drive native populations toward extinction by outcompeting them for resources. Additionally, some gastropods serve as intermediate hosts for parasites, linking them to the transmission of diseases like schistosomiasis.152