Navigating the Skies and Seas: A Drone Pilot's Perspective on Sperm Whales

Dr. Melissa Cook describes how a team used drones to study endangered sperm whales in the Gulf of America.

Survey |

NOAA Ship Gordon Gunter during the June-August 2025 survey in the northern Gulf of America. Visual observers on the flying bridge are watching sperm whales and the drone team records video of the whales. Credit: NOAA Fisheries/Melissa Cook (Permit # 27867)

On board NOAA Ship Gordon Gunter, our team studied endangered sperm whales in the Gulf of America. The information we collect will inform projects designed to restore injuries associated with the 2010 Deepwater Horizon oil spill. We deployed Uncrewed Aircraft Systems (UAS, i.e. drones) to capture high-resolution aerial imagery to document the body size and condition of these spectacular marine mammals.

The Team Effort

Obtaining UAS videos of sperm whales requires careful coordination between the scientific party and the officers and crew. Visual observers on the flying bridge diligently scan for whales while the acoustic team listens for their echolocation clicks. Together, these teams pinpoint where the whales are and when they will surface. The officers steer the ship toward the animals, positioning it to allow us to launch the UAS and attempt to reach the whales, which are often more than a mile away. Even flying at speeds of 35-45 miles per hour, it still can take several minutes to reach the whales and center them in the UAS's imaging system.

The Mission: Capturing Behavior and Size Data

Once the UAS reaches a whale, the camera is oriented straight down to collect high-definition video to obtain precise body measurements such as length and girth. We can record the whale for several minutes as it lingers near the surface and obtain images of the whole body of the animal from the video to make accurate measurements. We can also use the images to evaluate the health of the animal. The camera has multiple zoom lenses, so we can hover 100 feet or more above while the whales remain unaware of our presence. This wider view lets us record groups of whales and their behaviors without disturbing them.

Operational Realities

Placing the UAS over whales that can be up to 2 miles from the ship is a challenge, and we were not always successful. Without landmarks, we've discovered that clouds make great visual anchors in an otherwise empty horizon. If we can see a blow with the naked eye, navigation is simpler, but at greater distances, just a slight deviation of the UAS track line means missing the whale entirely. Sometimes by the time the UAS finally gets to the whales, the whales are below the surface or dive just a few seconds later. On good weather days, we launch a small boat to photograph, sample, and/or tag the whales. If that boat is nearby, it serves as a valuable landmark to help find the animals quickly.

The sperm whale's blow (red arrow) in the distance serves as a visual guide to help locate the whale with the UAS. Credit: NOAA Fisheries/Melissa Cook (Permit #27867)

Flying a UAS off a moving ship in a marine environment presents considerably more challenges than flying over land. The UAS is designed to have 43 minutes of flight time. But operational realities like wind and flight speed reduce our actual flight time to about 20-25 minutes, as no pilot would risk pushing the battery to its maximum. Because the Gordon Gunter is always moving, the drone's "homepoint" must periodically be updated. The drone calculates its remaining flight time based on that point; if it's still set to the launch location miles behind us, the system may miscalculate the battery power required to return to the ship's current position. Landing is the most difficult part of the operation. It is important to ensure a power buffer for hand-catching the drone too, which can require multiple attempts due to wind and the movement of the ship.

Using Photos to Measure Whales

Our work continues long after the ship returns to the dock. The UAS video we captured serves as the data for photogrammetry-the science of extracting precise measurements from aerial imagery. By applying a scale derived from flight altitude and the focal length of the camera, we can translate pixels into the physical dimensions of these animals. We carefully review our video footage to select optimal frames where a whale is positioned flat at the surface. We then input these images, along with flight altitude and sensor specifications, into specialized software to measure the animal's overall length and width at selected points along the body. Achieving an accurate measurement is complex. Factors such as the amount of the whale submerged, environmental conditions like glare or wave action, and the precision of the drone's altitude data all play a role. Even minor deviations in these parameters can affect our final estimates.

Fun fact: Sperm whales are the largest toothed whales! Males can grow to 67 feet long-almost as long as a tractor trailer. The whale shown below is estimated to be 23 feet long.

Sperm whale image with overlaid digital lines to accurately measure the whale's length. Credit: NOAA Fisheries/Melissa Cook (Permit #25867)

A Researcher's Perspective

Though my tenure with NOAA Fisheries spans nearly three decades, my journey as a licensed UAS pilot only began in 2022. My previous aerial missions were largely dedicated to surveying sea turtles via automated transects. This project was my very first time piloting a UAS to survey marine mammals. To prepare, I spent several months honing the flight skills and precision demanded by this specialized work. Witnessing these magnificent creatures from an aerial perspective is a rare privilege and undoubtedly a career pinnacle. The memory of my first successful mission on July 4 remains etched in my mind; capturing a mother and calf together justified every hour of preparation. Gaining this unique bird's-eye view into their lives, even for a brief moment, is truly an extraordinary experience.

The project was funded through the Open Ocean Trustee Implementation Group, as part of their monitoring and adaptive management activities. These activities are assessing how projects to restore natural resources injured in the Deepwater Horizon oil spill are making progress towards recovery in the Gulf of America. All activities are conducted under a scientific research permit (Permit #27867) and approval from the NOAA Institutional Animal Care and Use Committee.

Meet the Blogger

Dr. Melissa Cook serves as a Research Fisheries Biologist within the Marine Mammal and Turtle Branch at NOAA's Southeast Fisheries Science Center. Since Dr. Cook joined NOAA in 1997, she has spearheaded vital research on protected species and fisheries, contributing numerous peer-reviewed studies and essential data to support conservation management. When she's not flying UAS or analyzing data, she enjoys paddle boarding, cooking, travel, and spending time with her family.

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More Information

• Evaluating the Cumulative Impact of Multiple Stressors on Cetaceans Project
• Southeast Fisheries Science Center
• Marine Mammal and Turtle Division
• Eyes in the Sky: Using Drones to Measure Sea Turtles

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Last updated by Southeast Fisheries Science Center on August 24, 2026