Heat stress disrupts coral ventilation systems, study finds

The study examined how elevated temperatures affect cilia, the tiny filaments that create water flow across coral surfaces. When water temperatures rise, these structures slow or stop moving, reducing the corals' ability to ventilate and clear debris. Prolonged disruption allows waste and pathogens to accumulate, which can damage living tissue and weaken the colony over time.

Effects observed in laboratory conditions Experiments exposed coral samples to controlled temperature increases matching conditions recorded during recent marine heat events. Researchers tracked changes in cilia movement and measured resulting declines in water flow and waste removal.

The same experiments showed that extended exposure caused permanent loss of cilia function in some specimens, followed by visible tissue deterioration.

Implications for reef survival Coral reefs provide habitat for thousands of marine species and protect coastlines from erosion. Reduced ventilation capacity during heat stress periods adds another mechanism by which warming oceans can degrade reef structures.

Further laboratory and field studies are planned to determine whether some coral species maintain cilia function longer than others under identical temperature conditions.