Uncrewed aerial vehicles (UAVs) are advanced drones that provide valuable perspectives on marine life and phenomena from the air. MBARI’s growing fleet of aerial vehicles is gathering high-resolution, near-real-time data about the ocean that complements the information gathered by the institute’s oceangoing robots.
“The cameras on aerial drones give us a big-picture view of the ocean’s surface, including the signs of physical and biological processes that start deep underwater, such as upwelling. By combining aerial imagery, satellite information, and detailed measurements from MBARI’s underwater and surface vehicles, we can learn more about ocean health,” explained Tom O’Reilly, a senior software engineer on the team working on using UAVs for scientific research.
Weather permitting, twice every month, the UAV Team conducts an aerial survey of specific research sites around Monterey Bay. The scientists and engineers mobilize to launch a vehicle from the beach. A pilot plans the mission and initiates takeoff, and once the drone is in the air, it runs an autonomous survey. The onboard camera collects ocean surface images as the UAV zig-zags its programmed route offshore. During a typical survey, the vehicle might traverse 25 kilometers (15.5 miles) and image an area of 750,000 square meters (about a quarter of a square mile). UAVs are relatively quiet, providing unobtrusive observations of marine communities. The team coordinates the surveys with NOAA researchers to ensure the drone’s flight plan does not disturb marine life. Once its mission is complete, the drone automatically lands in a pre-programmed location on shore. Back in the lab, engineers download the data from the vehicle for analysis.
For the past two years, MBARI researchers have been using aerial drones to survey marine communities in Monterey Bay at sites offshore of Davenport Landing, Terrace Point, New Brighton Beach, and Seacliff State Beach in Santa Cruz County and off of Moss Landing and Monterey State Beach in Monterey County. Our aerial vehicles have photographed a diversity of marine life and phenomena. We have seen large animals like gray whales (Eschrichtius robustus), white sharks (Carcharodon carcharias), and bat rays (Myliobatis californica), as well as more elusive wildlife like by-the-wind sailors (Velella velella) and moon jellies (Aurelia sp.).
Periodic aerial surveys provide visual data that can serve as the foundation for studying marine ecology, especially the population dynamics of marine life.
“The power of these aerial surveys is that in practically every image, we observe a wide diversity of life forms and even marine debris,” explained Senior Scientist Steven Haddock. “As our capabilities grow, we plan to survey across the entire Monterey Bay regularly. The imagery we collect can support a number of science and conservation projects, from tracking the movements of iconic marine wildlife to monitoring the health of coastal ecosystems.”
MBARI’s UAVs carry high-resolution cameras that photograph objects, some as small as a paperclip, in remarkable detail. As the vehicle flies 60 meters (approximately 200 feet) above the ocean’s surface, it takes an image every two seconds. During a single 20-minute survey, the aerial vehicle takes approximately 400 photos. MBARI engineers combine these images to create a photomosaic of the surveyed area that can be processed using machine learning models. Although the camera on the UAV can capture high-resolution images with centimeter-level precision, it is challenging and laborious to differentiate the many organisms and phenomena embedded in the thousands of images.
“AI has allowed us to assess and analyze the array of imaging data collected by MBARI’s fleet of uncrewed aerial vehicles more effectively,” said Senior Software Engineer Danelle Cline. “The machine learning models group images with similar objects, then our human experts look at the outliers.”
An AI program called Slicing Aided Hyper Inference (SAHI) helps detect and classify objects. MBARI researchers group similar organisms and phenomena together based on shared visual features, allowing the SAHI model to examine them quickly. This approach removes the need for pre-labeled data to train an AI model, optimizing limited human resources. The more these models are used, the better they will get at classifying marine life and ocean phenomena.
Whether flying through the air, riding waves at the ocean’s surface, or gliding underwater, advanced technology provides a well-rounded understanding of ocean health.
Satellites have long been used to monitor the ocean on a global scale. From space, satellite camera resolution is typically hundreds of meters for a single pixel of the ocean surface. Clouds can obscure parts of the ocean. The satellite’s orbit and sensor characteristics can also result in time gaps of days or longer for any given patch of ocean. UAVs are not subject to these constraints. They fly less than 100 meters (328 feet) above the ocean and beneath clouds, resulting in a camera resolution of approximately one centimeter (less than half an inch) per pixel. They can be quickly deployed in response to short-lived events of scientific interest, although UAV flight operations can be limited by high winds or rain.
Aerial vehicles can support a variety of science applications. For example, by examining high-resolution images of the ocean’s surface, researchers can identify regions where upwelling brings cool, nutrient-rich water to the surface, leading to a bloom of plankton and marine life. Researchers can identify targets of interest in images acquired by UAV cameras and deploy in-water platforms for more detailed sampling. Aerial drones can provide a two-dimensional map of ocean color fronts from the air faster than an underwater or surface vehicle. Once they find a location of interest, our engineers can then program a long-range autonomous underwater vehicle (LRAUV) or Wave Glider to take a closer look.
Coordinated sampling with an aerial vehicle operating above MBARI’s advanced underwater robots enables a more thorough investigation of the physical, chemical, and biological processes that occur in the ocean. Together, they can produce a three-dimensional look at a research site. Last year, MBARI researchers deployed a UAV alongside an LRAUV carrying the Piscivore camera system. By scouting ocean conditions with a drone, researchers are able to deploy Piscivore where it would have the greatest chance of observing marine predators.
MBARI engineers are finding innovative ways to grow our UAV program further.
New onboard tech will allow the team to secure exceptions to regulations that currently limit operations to a one-kilometer line-of-sight, enabling operations farther offshore. MBARI engineers are also developing additional payloads that can be deployed on an aerial drone. In the future, aerial vehicles could be equipped with sensors to measure atmospheric particles and gases, which are crucial for studying marine ecology and understanding the ocean-climate connection. Incorporating onboard AI will also allow the vehicle to autonomously detect and respond to significant events in real time, like tracking whale pods or surveying thermal fronts.
At MBARI, we believe that collaboration is essential to truly maximizing the potential of science and technology to help us understand the ocean. The UAV Team is also exploring opportunities to collaborate with the Monterey Bay National Marine Sanctuary and other oceanographic research groups across Monterey Bay to develop more research applications for aerial vehicles.
“As MBARI’s uncrewed aerial vehicle program continues to grow, we’ll export our data and technology to scientists worldwide to facilitate their research and engineering efforts. We’re excited to help contribute to the research programs of various scientists and conservationists, whether they are interested in jellies, sharks, mammals, or kelp,” said Haddock.