It’s a complex marine language of calls, clicks and whistles, and scientists have only begun to skim its surface.
The study of the orca’s many dialects helps researchers develop a more complete picture of the whales’ behaviour — including how they socialize, feed and travel. Paul Spong and Helena Symonds, directors of a whale research station on Hanson Island, off the northeast coast of British Columbia’s Vancouver Island, have spent more than 40 years immersed in orca song.
Spong founded the research station, called OrcaLab, in 1979, after experimenting with hydrophones at the Vancouver Aquarium. “Hydrophones allowed us to open acoustic windows into the parts of the orca environment we couldn’t see,” says Symonds, Spong’s partner.
With the help of six of these underwater microphones, Spong and Symonds spend every day of the year monitoring a 50-square-kilometre area in the Johnstone Strait. The research station has also served as a permanent home for the pair (they even raised their daughter there), and only recently has the couple started wintering off the island.
That constant monitoring has enabled the pair to create sound profiles for each matriline group. “We had to learn how to identify these matrilines,” says Symonds, “and that took some time: sometimes the different orcas’ calls are very closely related.”
British Columbia’s pacific coast is home to four resident orca populations (clans) — three northern and one southern. Each clan is made of several pods, each led by a matriarch orca, and consisting of a few other matrilineal groups (a female orca and her offspring). There are more than 200 individuals in the northern clans and more than 90 in the southern resident community. Each pod has its own unique collection of calls, passed down from previous generations; clans are made of several pods that share common acoustic calls — or a “dialect.”
Over the years, Spong and Symonds have become intimately familiar with the calls of each pod, and can even recognize the sounds of individual orcas. In fact, the pods’ dialects are so recognizable that Symonds helped reunite a lost orca with her family back in 2002.
The orca’s name was Springer, and since losing her kin she had been following a ferryboat in Washington’s Puget Sound.
After analyzing Springer’s voice recordings, Symonds was certain the orca was more than 450 kilometres from her B.C. home and family pod. Thanks to that discovery, Springer was captured and brought back to B.C. to rejoin her pod. “Sometimes acoustic work is very satisfying, because it doesn’t lie,” Symonds says.
OrcaLab’s recordings now form an archive (called the “orchive”), at the University of Victoria. With over 20,000 hours of orca song recordings available to the public, the orchive is an invaluable research tool.
All that data represents decades of tireless hands-off collection and patience, yet as Spong says, it’s key to the orca’s continued protection and conservation. “And it has been so important for us not to disturb the whales,” he says. “We prefer them to go about their lives as they choose.”