Call of the wild: Foster Scholar Samara Haver studies sound across sanctuaries

By Yaamini Venkataraman

October 2017

The sounds of the ocean are an odd combination of haunting and soothing. From the crash of waves on the beach to the echo of whale songs, it’s tempting to believe putting a shell up to your ear will allow you to access the underwater soundscape whenever you need an escape. Unfortunately it doesn’t work that way. But Samara Haver has the next best thing: underwater sound recordings of national marine sanctuaries and national parks.

samara haver in a survival suit
Haver is one of the newest additions to the Dr. Nancy Foster Scholarship Program. She studies soundscapes, or the collection of all sounds in one area, at twelve different places, including national parks and national marine sanctuaries. Photo courtesy of Samara Haver

Haver is a Ph.D. student at Oregon State University, and one of the newest additions to the Dr. Nancy Foster Scholarship Program. At Hatfield Marine Science Center in Newport, Oregon, Haver spends her days listening to ocean soundscapes, or the collection of all sounds in one area.

Below the waves, marine organisms use sound to navigate their surroundings. Human-made noises—from ships, for example—can mask important natural audio cues. Much like carrying a conversation at a loud concert, it’s difficult for animals to communicate with each other, hunt, or even avoid predators when their environment becomes noisier.

the deck of a ship with haver in the middle front preparing a hydrophone mooring
Haver prepares a NOAA Pacific Marine Environmental Laboratory shallow-water hydrophone mooring for deployment. Photo courtesy of Michelle Fournet

“For a long time, people didn’t realize that noise was a form of ocean pollution, or that it was a problem. My work is particularly motivated by not only sharing that knowledge, but taking accurate and comparable measurements to help document it,” Haver says.

Working with the NOAA Ocean Noise Reference Station Network, Haver’s goal is to understand how much noise is present in wild spaces and where it’s coming from. Once she’s done, she’ll know more about what animals hear in national parks, unprotected marine waters, and four national marine sanctuaries — Olympic Coast, Channel Islands, Stellwagen Bank, and Cordell Bank.

map of noise reference stations
Map of Noise Reference Station sites. Haver’s research encompasses soundscapes from national marine sanctuaries, national parks, and general marine waters. In numerical order from "NRS01," she has hydrophones in the following locations: Alaskan Arctic, Gulf of Alaska, Olympic Coast National Marine Sanctuary, Hawaiian Islands, Channel Islands National Marine Sanctuary, Gulf of Mexico, southeastern continental U.S., northeastern continental U.S., Stellwagen Bank National Marine Sanctuary, Tutuila Island in National Park of American Samoa, Cordell Bank National Marine Sanctuary, and Buck Island Reef National Monument in the U.S. Virgin Islands. Map courtesy of Samara Haver

Haver’s first step is to record the soundscapes of her 12 study sites. To capture a soundscape, she uses a custom-built autonomous passive acoustic hydrophone—essentially an underwater microphone attached to a hard drive. She then deploys her custom hydrophones at sea. In the sanctuaries and other waters, she places her instruments both in shallow and deep water. After one or two years, Haver can collect her hydrophones and listen.

“We typically start by turning the audio files into a spectrogram,” Haver explains. “A spectrogram is basically a picture of the sound. Unlike marine animals that rely on sound to sense their surroundings, humans need both our eyes and our ears. By using spectrograms to review the data, we can look and listen at the same time to pick out interesting sounds and describe what is going on underwater.”

spectrogram
Haver uses spectrograms, like this one from Stellwagen Bank National Marine Sanctuary, to visualize the sounds underwater. Looking at a spectrogram and connecting it with what she hears, Haver can find interesting sounds. Image courtesy of Samara Haver
Samara’s recordings capture the underwater sounds that occur in the ocean. This recording was taken in Stellwagen Bank National Marine Sanctuary. Most of the sounds on the recording that are perceptible by the human ear are the vocalizations of a humpback whale. The audio recording and the spectrogram above match, so you can follow along as you listen. Audio courtesy of Samara Haver

For some areas, like Channel Islands and Stellwagen Bank national marine sanctuaries, this research builds on previous studies that have worked to describe sanctuary soundscapes. However, none of the national parks she’s working with have defined soundscapes, so her research will be the first piece of the puzzle in those locations.

haver with hydrophone
Haver deploys hydrophones like the one pictured here to understand how much noise is present underwater. Photo courtesy of Samara Haver.

Once she understands the sounds present at all of her study locations, she can then start to compare the sounds’ volumes and sources. That’s where things get tricky. Because marine soundscape research is relatively new, it’s up to Haver to develop and apply new methods to pinpoint key acoustic qualities within and among the listening locations. Her research can be used to better protect species and habitats sensitive to noise.

With her data, “we can ask how these soundscapes change and how might sanctuary management be affecting these soundscapes. The answers will be different for each sanctuary, but it provides an opportunity to make comparisons,” Haver says.

For the duration of her Ph.D., Haver will spend her days listening to the call of the wild—from whale calls to tumultuous storms. “I can sit in the lab and listen to the ocean in these different places. I can hear the animals, ships, and the weather as if I were there myself,” she says. “While I’m not at sea every day looking for the animals, I’m able to listen to them in a way that would be impossible without these technologies. I’m really excited that this project connects me to so many sanctuaries.”

Yaamini Venkataraman is a volunteer social media intern at the NOAA Office of National Marine Sanctuaries and a graduate student at the University of Washington.