Call of the wild: Foster Scholar Samara Haver studies sound across sanctuaries
By Yaamini Venkataraman
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.
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.
“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.
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.”
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.
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.