Fish biomass near oyster reefs is often 2–4 times higher than in adjacent areas.

A Natural Nursery

Oyster reefs function as vital habitat and nursery grounds for a wide variety of fish, crabs, shrimp and other commercially and ecologically important marine species. These structures enhance local fisheries by increasing biodiversity, biomass and survival rates of juvenile organisms.

The crevices and surface area of reefs protect juvenile fish and crustaceans from predation and strong currents - effectively acting as nature’s fish nursery.

Boosting Local Fish Stocks

Studies have shown that oyster reefs increase the abundance and biomass of economically important species such as:

• Snappers (Lutjanidae)

• Groupers (Serranidae)

• Prawns and shrimp (Penaeidae)

• Blue crabs (Callinectes sapidus)

• Mullet, anchovies, and gobies

Food Security and Livelihoods

By improving habitat and increasing prey availability, oyster reef restoration can contribute to long-term food security, support small-scale fisheries and reduce pressure on overfished stocks.

In regions like Hong Kong, restoring shellfish habitats may provide alternative income opportunities, encourage sustainable harvesting and contribute to resilient coastal economies.

Benefits at a Glance:

• Habitat Creation: Refuge and nursery grounds for fish and invertebrates.

• Increased Biomass: Higher density and diversity of marine species.

• Fisheries Recovery: Supports artisanal and small-scale fisheries.

• Sustainable Livelihoods: Alternative economic benefits to coastal communities.

• Ecosystem Balance: Enhances predator-prey relationships and trophic dynamics.

How It works:

• Shelter/nursery: Reefs reduce predation risk for juveniles.

• Foraging grounds: Reef complexity attracts invertebrates that fish eat.

• Water quality improvement: Oysters filter water, increasing clarity and enhancing benthic productivity.

• Biodiversity hotspot: Healthy reefs create an interconnected ecosystem supporting multiple trophic levels.