Unoccupied Aerial Systems
(Drones)

Unoccupied aerial systems (UAS; drones) have become an indispensable tool in marine mammal research. Their ability to rapidly cover large areas, track and hover precisely over individuals, and capture novel aerial perspectives enables researchers to collect high-resolution data quickly, efficiently, and in a largely non-invasive manner. At MMRP, we primarily use small quadcopters (with four propellers) equipped with high-resolution sensors, including visible-spectrum cameras and laser altimeters, to study the health, morphology, behavior, and ecology of marine mammals across a wide range of body sizes. However, as UAS technology has advanced, we have begun using these systems in increasingly diverse ways, transforming how we study marine mammals in Hawaii and abroad.

How it Works:

The target animal or group is located from a research vessel or shore before our UAS operations begin.
We hand-launch the UAS and fly it directly to the target group using a remote controller, with a camera on the UAS providing a live-feed on the controller screen.
We position the UAS over the target individual, typically hovering ~10 ft over the animal for tag deployment or breath sampling, or up to 130 ft for photogrammetry.
For most data streams, we record high-resolution video footage with the camera in nadir position, keeping individual subjects in center frame. If we are interested in measuring the size and shape of the subject, we link our videos with high-resolution flight metadata.
Researchers download the raw data and use standardized workflows to process and merge the various UAS data streams, ready for a suite of analyses.

Bioenergetics

Our UAS system enables precise photogrammetric morphometric measurements of free-living marine mammals that would otherwise be impossible to measure safely. From aerial imagery, we estimate a suite of metrics - including body length, width, and shape - which allows us to infer body mass and condition. By distinguishing which components of an individual’s body mass are related to structural size versus those that reflect energetic condition, we can quantify how marine mammals gain and lose energy naturally or in response to human disturbance. These morphometric estimates complement the bioenergetic approaches used in biologging studies, providing a stronger foundation for testing hypotheses and addressing questions that were previously considered very difficult to answer. We also use UAS to estimate the respiration rates of individuals across a range of behaviors, allowing us to model metrics of energy expenditure across body sizes and behavioral states.

Aerial photo-identification

UAS have greatly expanded the non-invasive identification of individual marine mammals by providing a high-resolution, overhead view of features that are difficult to document from a research vessel. These features are typically species-specific, ranging from tubercles and cookie cutter scarring to dorsal surface pigmentation. The aerial images captured from UAS platforms are typically processed using semi- or fully-automated pattern recognition software and algorithms. Overall, these efficient approaches enable researchers to track individuals across seasons and years, estimate population size and survival, and link health and behavior data to known individuals.

Tag Deployment

Biologging tags record detailed data from free-swimming marine mammals (see our biologging page), offering highly informative insights into their underwater lives. UAS offer a novel, minimally invasive deployment method: when an animal surfaces, a suction cup tag can be released from the drone and dropped precisely onto the animal’s back. Given the live-feed and mobility of the UAS, we can deploy tags on targeted individuals several hundred meters away from the research vessel, reducing the potential stress experienced by marine mammals when compared to traditional vessel-based approaches.

Group Size, Age-Structure, and Behavior

The aerial perspective provided by UAS gives researchers a uniquely comprehensive view of marine mammal behavior, allowing detailed documentation of animal activities often affected by vessel presence. With extended battery life and a wide range of allowable flight altitudes, UAS have become critical tools for studying the foraging tactics of various species, estimating group size, and observing how individuals interact with one another. They also allow us to quantify the proportion of time animals spend engaged in specific behaviors such as feeding, resting, traveling, and socializing. When combined with photogrammetric methods, UAS are highly effective for estimating body length across large sample sizes, allowing researchers to infer the age structure of free-living populations. These data are critical for assessing how human disturbances alter natural behavior, with direct implications for individual health and population-level conservation management.