New Non-Invasive Drone Method Determines Sperm Whale Sex and Age from Aerial Photos

Thu, 16 Apr 2026 14:48:00 +0200

Researchers have developed a minimally invasive technique using uncrewed aerial vehicles (UAVs), or drones, to determine the sex and developmental stage of sperm whales in the wild. The study, conducted off the Galápagos Islands with 51 individuals, relies on photogrammetry to measure body lengths and other morphometric features from overhead images. These measurements are compared against historical whaling data on sperm whale growth curves and sexual dimorphism to assign developmental stages, such as calves, juveniles, subadults, or adults. A Bayesian statistical approach then estimates the probability that an individual is female based on body shape and size differences between sexes. The method achieved confident classifications for most whales examined. Additionally, the team analyzed peduncle diving behavior—a specific diving pattern—and found it aligns with prior observations: it is mainly performed by subadult males and directed toward females. This approach provides an efficie