Scientists are using drones to monitor an elusive marine mammal species that lives in Hawaiʻi's waters.
False killer whales are not whales at all, but a type of social dolphin. Their small numbers and curious personalities make them difficult to track and observe.
Scientists at the Pacific Whale Foundation on Maui found that they could accurately measure the size and estimate the weight of Hawaiʻi's false killer whales using aerial drone videos.
The results reveal startling fluctuations in the conditions of these rare dolphins.
Jens Currie is the chief scientist at the Pacific Whale Foundation. He spoke with The Conversation about the new research and this fascinating species, which numbers fewer than 150 around the islands.
Currie said that the species is distributed around the world, but Hawaiʻi has a special population of false killer whales who evolved in the islands. However, this has put them in direct conflict and overlap with human activities, resulting in a population decline.
In 2012, the species was listed as endangered.
“Since then, they have unfortunately still been steadily declining, and so our current best estimate is 139 individuals, and we lose around five to six individuals per year,” Currie said. “So that trend is going the wrong way. They're still listed as endangered, and I'd consider them one of the most endangered dolphin populations in the U.S. right now."
With the help of drone technology, Currie and his team measure the species' length and width to get a body condition score, which helps determine the animal's health.
“What that tells us is that ratio of length-to-width at a given point in time, and then we would expect that ratio of length-to-width to stay the same over time. But if we're seeing it decrease, then that animal is losing weight, becoming poor condition. Or if it's gaining weight, we'll see that length-to-width ratio increase,” Currie explained.
He added that false killer whales in Hawaiʻi do not migrate, so scientists expect them to remain at the same length-to-width ratio. However, new research revealed large fluctuations in measurements.
“It was surprising to see how drastic that drop in body condition ultimately was. One individual lost 500 pounds in just a few months,” Currie said. “And so being able to quantify that on such a precise scale is really important, but the sheer magnitude of that is crazy. It's a quarter of the body weight, and so that was definitely surprising."
“The other surprising aspect was that almost the entire population, at least those that we measured, could be impacted in a single year as a result of a single event," Currie said. "And so it just goes to show that these individuals are living on a very finite amount of energy.”
Currie said that a positive is that all the individuals that they measured are still known to be alive. Despite intense weight-loss events, the species shows it can bounce back. He hopes to create more false killer whale advocates so that the public has greater awareness of the species.
Find more information about false killer whales here. Click here to view Currie's research about the endangered species.
This story aired on The Conversation on June 16, 2026. The Conversation airs weekdays at 11 a.m. Hannah Kaʻiulani Coburn adapted this story for the web.
