Beluga whales are a charismatic species, easily recognized–and adored–for their bright white color and prominent foreheads. New research from Justin Richard, assistant professor of animal science, published in Animal Cognition suggests there may be more to those squishy, distinctive heads than previously thought.
In the decade Richard spent as a beluga whale trainer at Mystic Aquarium in Connecticut, he noted something well observed by scientists but not well understood: the different shapes the animals make with their melons, the large fat deposits on their foreheads that are noticeably malleable, didn’t seem to be entirely random. Since joining the faculty at the University of Rhode Island, his research has focused on understanding the reproductive physiology and behavior of belugas to inform conservation efforts. His curiosity about the melon shapes stuck with him, though.
“Nobody had ever really done formalized research about what exactly they are doing with their heads, in what context they are doing it, and why,” Richard says. Over the course of several years, he and a team of students at URI sought to do just that. They analyzed recorded interactions between four belugas at Mystic Aquarium, cataloging details about 2,500 different shapes–such as how long they lasted for, what behaviors were occurring before and after the shape, who the recipient whale was, and more. The data revealed a striking pattern: melon shapes seem to be a nonverbal communication method between belugas. “Based on the research, it’s not simply an unconscious reflex,” Richard says. “It seems to be purposely done to communicate some signal to a recipient.”
Belugas are the only species of toothed whales that can alter the shape of their heads. “My big question is why,” Richard says. “When you watch these animals interact, it’s very clear how important visual displays are in their communication. They take on different postures and swim positions, and their bodies contort in different ways.” And while they are also known to be very vocal, making a variety of sounds from whistles to clicks, the emphasis on physical expressions stands out. “They live in the arctic, which has very little daylight for huge chunks of the year,” Richard notes. “So why invest all of this in visual communication?”
His research suggests there’s a compelling reason for them to be able to see each other. Their striking, distinctive bright white color has often been assumed to allow them to camouflage against the ice in the arctic, but if that is the case, the fact that their babies are born dark gray–and that their bright coloration actually makes them quite visible in murky water–has always seemed puzzling to Richard. “It’s just a personal hypothesis, but I really think they’re that color so they can see each other do these visual displays in low light settings,” he says.
With a team of undergraduates mining several thousand examples, Richard is now exploring another prominent visual cue: open mouth displays. Because these expressions are used in varied behavioral contexts– from courtship to play to aggression–Richard suspects they modulate the meaning of their open mouth by what they do with their heads. The data they work with does not include acoustic recordings, something he hopes could be included in future studies for a more comprehensive view of these interactions. “There are a lot of questions about whether or not changing the shape of their heads somehow changes how the sound is perceived by recipients or if they can further modify the meaning of sounds by the way their head is shaped,” he says. “The same behavior might take on different meanings with other context cues.”
URI students have been instrumental in Richard’s research, spending hundreds of hours analyzing video footage. They earn academic credit for working on the project, and some who have since graduated found their contributions helped propel them into other opportunities. Richard’s two co-authors of the research paper in Animal Cognition, Isabelle Pellegrini and Rachael Levine, who were undergraduates at the time of their participation, have gone on to exciting career paths: Levine is now a sea lion trainer at Mystic Aquarium, and Pellegrini just finished her Master’s degree at Tufts University. “The College of Environment and Life Sciences takes great pride in experiential learning opportunities,” Richard notes.
Ultimately, this ongoing study relates to Richard’s research on reproduction. “If they’re spending a lot of time communicating about reproduction and their quality as a potential mate, it has implications for understanding how these animals breed in the wild,” he says. As for the general public, Richard hopes this new understanding about nonverbal communication between belugas leads to a great appreciation for the work that can be done in zoos and aquariums. “We cannot watch these animals under water in the wild without seriously impacting their behavior,” he says. “Watching them in the aquarium gives us clues we wouldn’t have otherwise, and it can shape new approaches that we hope to have an impact on the conservation and management of wildlife.”