Ultrasound Scans Reveal Coral Reproduction Without Harm

Canon has, for the first time, scanned live corals underwater and observed developing eggs without damaging the colonies. The method will help researchers study spawning and plan reef restoration more precisely.

Underwater Ultrasound of Corals: Canon Helps Detect Developing Eggs

Coral Spawning International (CSI), together with Canon Medical Systems UK and Canon EMEA, has conducted the world’s first ultrasound examination of live corals while they remained underwater. The scan revealed developing eggs inside the colonies without damaging them.

The experiment used a Canon Aplio i700 medical ultrasound system. Researchers studied six species of large polyp stony (LPS) corals and obtained images of the internal structures of their eggs. Previously, researchers had to cut open a coral or sacrifice it to study its reproductive condition.

The scans were compared with macro photographs of the coral Trachyphyllia geoffroyi. This comparison confirmed the ultrasound results.

How the Internal Structures Were Revealed

The team combined high-frequency and ultra-high-frequency probes. Ultrasound with greater penetration depth produces images with lower resolution, while ultra-high frequencies provide greater detail but penetrate less deeply. Using both frequency ranges gave the researchers a more complete picture of the internal structures of the corals.

Coral Spawning International co-founder Dr Jamie Craggs noted that the reproductive processes of corals are still not fully understood. The ability to observe them inside a living colony, he said, opens up a new way to study the reproductive cycles of different species. CSI plans to continue observations during spawning to build a more detailed picture of these processes over time.

For conservation projects, accurately determining the stage of egg development could help researchers predict spawning times more reliably. This is important for coral breeding in laboratories, selective breeding, and reef restoration: knowing the right time will make it possible to plan these efforts more effectively.

Potential for Medical Imaging

Sally Davey, clinical product specialist at Canon Medical Systems UK, said the experiment demonstrated the capabilities of ultrasound imaging. The successful scanning of corals, she added, also points to possible applications for similar technologies in minimally invasive surgery and the diagnosis of skin conditions.

Peter Bragg, director of sustainability and government relations at Canon EMEA, connected the result to the broader role of imaging techniques: they help gather data about objects that were previously inaccessible to observation and deepen our understanding of the world around us.

The corals involved in the experiment will be monitored for another six months. Researchers plan to record when they release gametes—the mature sex cells. These records will help CSI study the reproductive cycle of corals more precisely, identify spawning periods, and apply the findings to future reef conservation and restoration programs.