Thermal drones can track dolphin health without having to touch or disturb them

ADELAIDA: Marine mammals are sentinels of the sea. When dolphins and whales show signs of stress or illness, it often signals deeper problems in the ocean ecosystems we all depend on.

But assessing the health of dolphins and whales is notoriously difficult. That’s because they spend most of their lives underwater, move over vast areas, and cannot be examined closely without causing stress or disturbance.

Our new research provides a promising solution to this problem.

Published in the Journal of Thermal Biology, it shows how drone-mounted thermal cameras can help monitor dolphins’ vital signs such as skin temperature and breathing patterns.

Scientists have typically relied on hands-on methods to assess the health of wild marine mammals. These include attaching tagging devices or taking measurements during capture and handling.

While these methods can be effective, they are also invasive, expensive, logistically complex, and can alter the animals’ behaviour and physiology. This can induce stress, making results harder to interpret.

To fix this problem, researchers need tools that allow them to monitor dolphins repeatedly and accurately, while minimising disturbance.

One example is drones fitted with thermal cameras.

Thermal cameras detect heat emitted from surfaces, allowing temperature patterns to be measured remotely.

When mounted on drones, they can potentially record this information from above, while animals continue to move freely.

In the case of dolphins, they have the potential to measure skin temperature and breathing patterns based on the heat emitted from the animals’ blowholes, body and dorsal fin, without having to get close or touch them.

But until now, no studies have tested how accurate, reliable or practical this approach is in real-world conditions.

In our study, we used a drone-mounted thermal camera to measure dolphins’ body surface temperature and breathing rate under controlled conditions designed to reflect how dolphins are monitored in the wild.

The study involved 14 adult common bottlenose dolphins under human care at Dolphin Beach, Sea World on the Gold Coast, Australia. Testing was conducted across different heights, camera angles and environmental conditions to validate drone-based measurements.