Humpback whale songs are choreographed to match deep dives, study finds

A new study reveals a direct link between the structure of a male humpback whale’s song and its physical movement during a dive cycle. Scientists have long studied these prolonged serenades, but this research bridges acoustic patterns and physical physiology. Syracuse University in New York found that whale songs are directly structured around the depth, buoyancy, and oxygen management of a dive. Surprisingly, some humpback whales sang continuously for up to 16 hours, with specific song “themes” mapping consistently across an entire dive cycle for the first time. Researchers attaching a suction-cup recording tag to a humpback whale off the coast of Maui. Credit: Credit: Julia Zeh; NOAA NMFS Diving to the beat How do you track a singing giant? Very carefully, and with a pole. Between 2018 and 2024, the research team tagged 16 male humpbacks off the coast of Maui. Using long poles and drones from small boats, they attached tablet-sized, suction-cup recording devices to the whales’ backs. These non-invasive tags tracked both movement and sound. The devices eventually popped off, floated up, and surrendered their treasure trove of data. What the researchers saw was surprising. Some males sang continuously for up to 16 hours. Even more fascinating was the precision of their choreography. Certain themes were consistently sung while descending, others while ascending, and an entirely different set while hovering at the bottom. The study suggests that a humpback’s song acts as a physiological display of strength and stamina. At maximum depth, where water pressure is intense and depth is stable, the musical themes showed high variation between individuals. This is likely where sexual selection kicks in. It’s the humpback equivalent of a vocal flex, showing potential mates and rivals that the singer has the lung capacity and fitness to pull off complex variations deep underwater In contrast, themes performed during ascents and descents are constrained by physiological demands like oxygen management and buoyancy control. “This gives us direction for which parts of the song to investigate if we’re interested in variation, which is likely driven by sexual selection,” said Julia Zeh, a Ph.D. graduate in Syracuse University’s College of Arts and Sciences (A&S). Eavesdropping for protection Building on years of doctoral fieldwork at Syracuse University, Zeh pioneered the combination of bioacoustics and biologging movement data to reframe how scientists study humpback whale song. These findings bridge acoustics and movement to provide unprecedented insight into the evolution and biological constraints behind humpback whale songs. Connecting humpback song structure to dive depth helps to estimate a whale’s position using acoustic monitoring alone, creating a baseline for normal behavior to better detect human disturbances like ship traffic and noise. While physiological factors likely apply to humpbacks everywhere, differences in song evolution across global populations mean further international tagging studies are needed to confirm whether this depth-song pattern holds outside Hawaiian waters. Researchers can now test if humpback populations in other oceans follow the same physical choreography, opening new doors for marine protection worldwide. The findings were published in the journal Current Biology on August 3.