Listening for ocean health
By Michelle Hines
When the ocean tells its story, Dr. Patricia Gray is there to listen. Gray, a biomusic researcher in UNCG’s Music Research Institute and director of its BioMusic International Research & Education Program (BIREP), has teamed up with researchers and conservationists in Mexico to put marine sounds on the map.
Gray uses hydrophones to record and analyze sounds in waters around the Mesoamerican Reef, the world’s second largest reef system. She and her students eventually will produce sound mappings that can help wildlife authorities preserve and manage marine resources.
“Typically science has tried to look at things, and that’s complicated to do in oceans,” Gray says. “We’re trying to understand the relationships of sounds in a healthy, biodiverse ecosystem.”
Knowing what a healthy, “normal” system sounds like can help inform us about the impact of seasonal changes, lunar and tidal cycles, invasive species and even seismic events on life at the reef. As Gray puts it, “normalcy is associated with safety.”
UNCG signed an agreement last November with the Government of Mexico’s National Fisheries Institute (known as INAPESCA) to advance the BIREP’s research on fish behaviors. INAPESCA is part of Mexico’s Ministry of Agriculture, Livestock, Rural Development, Fisheries and Food.
Three BIREP hydrophones are deployed in diverse areas: at a protected barrier island; in a migratory channel outside the reef at a depth of about 45 feet; and in an underwater sculpture garden where tourists dive and snorkel. Each hydrophone records 30 second soundbites every 15 minutes. Divers bring them up every six months to retrieve data and perform maintenance.
Of particular interest to Gray are cenote fish, a native species endangered by tourism and urban development, and lionfish, an invasive species that can destroy an ecosystem.
“Lionfish have overwhelmed a lot of areas in this particular reef system,” Gray says. “U.S. coastal waters have been spared so far, but I read recently that lionfish have begun to arrive in our southern waters.”
One potential application for Gray’s work is to use sounds that might repulse or change behaviors of lionfish. It might also point to better ways of fishing for the lionfish, which can be eaten safely once its poisonous barbs are removed.
“The good news is that lionfish are tasty and could become an attractive addition to our menus if it’s marketed well.”
Conversely, her work can identify what sounds make the reef pleasant enough that native species will thrive. If a sound environment can influence behaviors in unwanted species, Gray explains, it follows that it also can support survival for preferred species.
Gray is fascinated by the whale shark, the largest fish in the sea, which can reach upward of 40 feet long. She has swum with them off the Cancun coast and is intrigued to find out whether they produce any particular patterns of rhythms or sounds. That research could lead to better understanding of the species and what brings them to return to the same waters each year.
“The presumption is that whale sharks make no sounds,” she says. “But some people will tell you they hear sounds that they believe are made by whale sharks.”
Gray, who came to UNCG in 2004, built a reputation as a concert pianist before expanding into biomusic research. She was artistic director and pianist for National Musical Arts (NMA), the resident ensemble at the National Academy of Sciences in Washington, for 21 seasons and, in 1986, founded NMA’s BioMusic Program.
Gray’s biomusic research addresses musical structures and processes in other species and also includes the musical perceptions of bonobo apes and of humpback whales.
“This marine research is a whole new spectrum of activity for UNCG, and this institution is way out front in this biomusic approach,” she says. “We can inform other scientific research from a perspective that’s not typical. We’re bringing new tools to questions of how these ocean creatures interact with their external world.”