Trophic Ecology of Benthic Suspension Feeders

Benthic suspension feeders are sessile or slow-moving organisms that intercept particulate organic matter and plankton from the water column. They encompass diverse taxa, including sponges, bivalves, corals and ascidians, and form the architectural basis of marine animal forests. By filtering seston, these organisms mediate benthic-pelagic coupling, transferring energy and nutrients from surface waters to the seafloor. Their feeding strategies range from strict heterotrophy to mixotrophy, whereby autotrophic symbionts provide photosynthate alongside captured prey. The efficiency of particle capture is influenced by colony morphology, polyp or siphon structure, hydrodynamic conditions and food-pulse events. Beyond their role in the food web, benthic suspension feeders contribute to biogeochemical cycles, notably carbon sequestration in long-lived skeletal or tissue structures. They enhance habitat complexity, furnish refugia for associated fauna and serve as indicators of environmental change. Understanding their trophic ecology is crucial for predicting ecosystem responses to ocean warming, acidification and anthropogenic disturbance, and for informing conservation and resource-management strategies on coastal and deep-sea reefs.

Research from Nature Portfolio

Seminal investigations have quantified carbon immobilisation by gorgonian corals, revealing that these benthic suspension feeders act as modest but persistent blue-carbon sinks. Growth, respiration and feeding rates were integrated with population density and biomass measurements to estimate annual carbon sequestration in marine animal forests. In parallel, studies on soft corals have employed stable isotope tracers to dissect the balance between autotrophic carbon acquisition by dinoflagellate symbionts and heterotrophic feeding. Findings demonstrate species-specific differences in carbon fluxes, with symbiont density modulating productivity and resource allocation. These insights underscore the functional diversity among octocorals and point to potential shifts in trophic dynamics under changing environmental regimes.

Trophic Ecology of Benthic Suspension Feeders publication trend

The graph below shows the total number of articles in trophic ecology of benthic suspension feeders across all publications each year (not limited to Nature Index journals).

Technical terms

Benthic suspension feeder: An organism that feeds by filtering particulate organic matter from the water column and resides on or near the seabed.

Benthic-pelagic coupling: The process by which energy and nutrients are exchanged between the water column and the benthic environment.

Seston: Suspended particulate matter, including detritus, phytoplankton and zooplankton, available as food for suspension feeders.

Mixotrophy: A nutritional strategy combining autotrophy (via symbiotic photosynthesis) and heterotrophy (through particulate feeding).

References

1. The importance of coastal gorgonians in the blue carbon budget. Scientific Reports (2019).
2. Productivity and carbon fluxes depend on species and symbiont density in soft coral symbioses. Scientific Reports (2019).
3. Polyp expansion of passive suspension feeders: a red coral case study. PeerJ (2019).
4. The Importance of Food Pulses in Benthic-Pelagic Coupling Processes of Passive Suspension Feeders. Water (2021).
5. Marine Animal Forests of the World: Definition and Characteristics. Research Ideas and Outcomes (2022).
6. Multiscale flow between the branches and polyps of gorgonians. Journal of Experimental Biology (2023).