Coral Reef Ecosystem Dynamics and Sponge Interactions

Coral reef ecosystems are among the most diverse and productive marine habitats, underpinned by complex interactions between reef‐building corals, sponges, algae and other sessile organisms. Sponges contribute to nutrient cycling, water filtration and habitat structuring, yet certain encrusting species can become aggressive space competitors, overgrowing live corals and altering community composition. Environmental stressors such as temperature anomalies, nutrient enrichment and sedimentation can shift the balance of these interactions, favouring sponge proliferation in zones of degraded coral health. Stable isotope studies and in situ experiments have revealed that some coral‐killing sponges deploy both physical shading and chemical metabolites to damage coral tissue, while deriving relatively little nutrition from coral biomass itself. Conversely, healthy reefs with intact herbivore populations and complex topography tend to resist sponge overgrowth through enhanced competition and grazing. Understanding these dynamics is critical for predicting ecosystem trajectories under climate change and for devising targeted interventions, such as spatial management, shading or substrate restoration, that support coral resilience and maintain reef functionality on a global scale.

Research from Nature Portfolio

Recent studies have elucidated the mechanisms by which the cyanobacteriosponge Terpios hoshinota overgrows stony corals, demonstrating that a combination of light blockage and sponge‐derived toxins rapidly induces coral tissue necrosis, yet isotopic analyses show that the sponge’s nutritional gain from underlying corals is limited, indicating substrate acquisition rather than food extraction as its primary driver. In a complementary investigation, researchers have documented a specialised snail species living within T. hoshinota tissue, revealing a close association that may influence sponge demography and dispersal, though direct predation on the sponge remains unconfirmed. Together, these findings deepen our understanding of the biological and ecological nuances that govern sponge–coral interactions.

Coral Reef Ecosystem Dynamics and Sponge Interactions publication trend

The graph below shows the total number of articles in coral reef ecosystem dynamics and sponge interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Encrusting sponge: A sponge growth form that spreads as a thin layer over hard substrates.
Stable isotope analysis: A technique for tracing the origin and flow of nutrients via naturally occurring isotope ratios.
Sessile organism: An organism fixed in one place, unable to move, such as corals, sponges and algae.
Spatial overgrowth: The process by which one sessile organism grows over and covers another, often leading to the competitor’s decline.

References

1. Testing of how and why the Terpios hoshinota sponge kills stony corals. Scientific Reports (2021).
2. The coral-killing red sponge Clathria (Microciona) aceratoobtusa (Porifera: Demosponigiae) invades various coral communities of Gulf of Mannar Marine National Park, southeast India. The European Zoological Journal (2020).
3. Short-term in situ shading effectively mitigates linear progression of coral-killing sponge Terpios hoshinota. PLOS ONE (2017).
4. Substratum selection in coral reef sponges and their interactions with other benthic organisms. Coral Reefs (2023).
5. Snails associated with the coral-killing sponge Terpios hoshinota in Okinawa Island, Japan. Scientific Reports (2021).