Purrs, Moans and Shrieks from the Deep

In their foraging grounds of the dark, frigid waters in southeast Alaska’s Fredrick Sound, humpback whales are calling to one another with “purrs,” “shrieks,” “wops” and “moans.” To find out why they speak and what they might be saying, Oregon State University graduate student Michelle Fournet is listening.

Fournet and her hand-picked team of research interns have spent the last few summers collecting bioacoustics data on these whales, classifying and cataloguing their sounds to build a comprehensive “vocabulary” and to gain insight into the animals’ foraging and communication behaviors.

An historic lighthouse serves as both lab and lookout tower for Fournet and her team. When she was looking for a research project, she approached Andy Szabo, a courtesy professor in OSU’s Marine Resource Management Program and director of the Alaska Whale Foundation. He told her, “I have a lighthouse if you have a project.”

Standing vigil over a cluster of outcroppings called Five Finger Islands, the 78-year-old white lighthouse offers a unique vantage point for gathering scientific data — but with a mystical aura. Its fairy-tale quality inspired the initiative’s nickname: “The Rapunzel Project.”

The Rapunzel team tracks the whales’ locations from the lighthouse while also collecting sounds via hydrophone from a small vessel. Because no large research ship is used, noise that could interfere with the underwater soundscape is minimized.

Listening In

In her sunlit office in Strand Agricultural Hall, Fournet perches atop her yoga ball chair in front of a laptop computer. The screen is covered in spectrograms (pictorial representations of sound). The dark-gray peaks and valleys look like the output from a heart monitor. Amidst a jumble of buttons and settings, she clicks “play.” The patterns begin to amble across the screen.

A low tone, punctuated by a soft, high-pitched note, rumbles from her desktop speakers. “That one is a ‘purr drop,’” says Fournet. “This next one I believe is a ‘ribet.’” Another sound emanates eerily, a pattern of low, whooping chirps. “We use subjective classifications, along with statistical analysis, to classify sounds.”

These audio files were collected with bioacoustic equipment. Bioacoustics is the study of sounds made by living things, and for Szabo and Fournet, it is the best way to study animals whose behavior is mostly out of sight. Studying whales presents some obvious challenges. Humpbacks — although known as a more surface-dwelling species than most whales — still spend about 90 percent of their time underwater.

Although Frederick Sound remains relatively unaffected by vessel traffic and other human activities so far, such noises in the North Pacific are increasing and may affect how whales and other marine mammals communicate. Studies like Fournet’s can help scientists establish a baseline for studying noise impacts as vessel traffic mounts. “If you want to really look at how animals in a dark, viscous environment are interacting, acoustics end up being the way to go,” says Fournet. “If you want to understand how they are interacting, you need to learn to listen.”

Sounds in the Sound

The sampling day begins at dawn, when two interns wearing bright-red Mustang Skiff Suits (for floatation and insulation) motor into Fredrick Sound on a 10-foot Zodiac equipped with radios and hydrophones. They deploy the “phones” into the water. And then they listen, writing down whale sounds detected among the other background noises from the sea. Simultaneously, technicians in the tower scan the water for whales with binoculars, looking for a tail, a fluke or a spout from the whales’ blowhole. Nearly 20 meters tall, the lighthouse dwarfs its three-and-a-half-acre island. The protocol is literally bottom-up, beginning with recording the underwater sounds and then locating them from the lighthouse high above the water. Next they employ a surveyor’s device known as a Theodolite, which uses angles along with latitude and longitude to locate the whale. Basically, it’s trigonometry. They also record the whale behaviors such as surfacing and group interactions. The behavioral data are overlaid with the acoustic data to have a multidimensional dataset in conjunction with the whale calls themselves.

“So we can say to ourselves, ‘This is what the distribution of whales looks like, this is how many there are, this is the kind of groups that they’re traveling in and this is what the ocean sounds like,’” Fournet explains. “And we’ll do that for anywhere from nine to 12 hours, minimum, on a sampling day. Sometimes we’ll bump it up to 18 if it’s a really long day.”

Island-Bound

Before Fournet’s move to Alaska in 2006, she had never seen a whale. She took a job as a naturalist aboard a whale-watching vessel. It was exciting, but something tugged at her conscience. “It felt selfish to be watching and taking — that there was this big industry and a lot of money involved with this animal that we actually didn’t know as much about as I thought,” she says.

So Fournet began to volunteer with a graduate student who was studying whales at the University of Alaska in Juneau. “That’s how I really got my foot in the door,” she says. “It helps a lot to live in a place where there are whales.”

She went back to school, completing post-baccalaureate work at the University of Alaska in marine biology. It was there she approached her current adviser, Andy Szabo. After developing the rigorous sampling protocol alongside Szabo, Fournet realized that this was more than a one-woman job.

“When I realized that there was no possible way I could do it by myself, it was actually very exciting to think that I could bring on technicians,” she says. “I could bring undergraduates who really wanted to study whales, and I could take them to this magical place to work on a project where they could build a skill set that they could use in the future.”

During their four-week sampling sessions, the interns rotate between launching out on the Zodiac, working with the Theodolite on the tower and processing and receiving data. Extreme temperatures, fog and rough seas are constant challenges.

With the nearest village 30 miles away by sea and by land, supplies and water must be used carefully. Electricity, too, is a precious commodity. Solar, wind and generator power provide only about six hours of electricity a day for their needs, including charging laptops and other equipment. Then there’s cooking, a silver lining for the island-bound researchers.

“It ends up being as much a summer about teaching people how to cook — making gourmet meals and breaking bread as anything else,” Fournet says. “I taught them how to fillet fish and collect berries, how to make an apple cobbler if all you have is apples and flour. You really get to know how to be resourceful, how to make your fresh vegetables last, how to freeze things. We ate really well.”

The research group also got comic relief out of the landscape and charisma of the lighthouse itself. The original five interns all happened to be female, so they joked about being “locked up in their white tower” just like Rapunzel. And the faithful Zodiac that tossed about in the chilly Frederick Sound in order to deploy the hydrophones? It was known as Noble Steed. “If you are in the lighthouse and you are downstairs, you are in the dungeon,” she reports. “And my adviser? We just called him Troll.”

Her interns unabashedly call her “Mama Michi.”

“Michi handled every problem with grace and levelheadedness,” writes 2011 intern Ryan Meeder on the project’s blog. “Michi was always willing to answer our many and often repetitive questions and to help us with anything and everything.”

To Fournet, mentoring her interns and communicating with the larger project are among the most rewarding parts of the program.

“It is really important to me that the Rapunzel Project helps people,” Fournet says. “Whether or not that’s just a small group of interns that I bring to the lighthouse or the people I interact with as a researcher for the Alaska Whale Foundation, humpback whales are a really great gateway to get people interested and engaged about learning about the ocean.”