The results from a study published recently in the Journal of Thermal Biology showed Infrared Thermography mounted on drones to measure the health of bottlenose dolphins (Tursiops truncatus), was able to detect localised thermal anomalies in a dolphin’s skin, highlighting the potential for drone-IRT to be a non-invasive tool for monitoring the health of managed and wild dolphin populations.
Marine mammal experts from Flinders University led the study that monitored 14 adult dolphins, in collaboration with Queensland’s Sea World, over a summer and winter season. The team analysed more than 40,000 drone-based thermal images to test how accurately drones equipped with thermal cameras could reliably measure dolphin surface temperature and breathing rates, without the need for capture or invasive probes like tagging devices.
Lead author Charlie White, a PhD candidate at FU’s College of Science and Engineering, and the Cetacean Ecology, Behaviour and Evolution Laboratory, said monitoring dolphin health was important to assess environmental impacts and to support conservation, but because these marine mammals spend most of their lives underwater traditional health checks often required capture or restraint. This can prove logistically challenging and potentially stressful for the dolphins, particularly in the detection of early signs of trauma, disease or physiological stress.
“At the optimal flight conditions – 10m to 15m directly overhead of a dolphin – we confirmed the drone measurements were precise enough to detect biologically meaningful changes in surface temperature and respiration rate – two important indicators of physiological state and health. We found the drone could reliably measure the heat coming from the dolphins’ blowholes, body surfaces and dorsal fins, as well as accurately count their respiration rate,” White said.
Senior author Guido Parra, Associate Professor at FU’s College of Science and Engineering, said the drone-IRT was a promising tool for wildlife health assessment, and opened the door to safer and less invasive health monitoring of marine mammals in both managed care and wild settings. IRT has been applied across a broad range of veterinary and wildlife contexts to assess health status, injury, vascular change, disease processes and physiological condition, including applications in domestic livestock, wildlife and animals under human care.
“Our findings show that drone-based infrared thermography can accurately and reliably estimate dolphin vital signs under controlled conditions. With continued refinement and testing under a wider range of wild conditions, the approach has the potential to support safer and less intrusive health monitoring of marine animals in managed care, and in wild settings,” he said.
Although the small sample size limits broader applicability, and further studies that incorporate clinical validation and more individuals will be essential in establishing the biological meaning of hotspot anomalies and their wider applicability, the researchers said that as a novel tool drone-IRT can extend existing health monitoring techniques, and it aligns with the growing use of drones in marine mammal research.
Anne Layton-Bennett
