By: Emma Thomson
Coral reefs are often referred to as “the rainforests of the sea” due to the incredible biodiversity of the plants and animals that live there. It is not surprising then that they share many similarities such as their complex interwoven ecosystems, their ability to draw tourists and nature lovers to wonder at their beauty, and even the incredible amount of sound they produce. Think about it… Rather than a parrot squawking, you can hear a parrot fish chomping! Coral reefs produce immense acoustics underwater that we are just not attuned to hear. As shocking as it might be, coral reefs have their own wonderful soundscape, and you guessed it- the louder the better!
In an early 2016 study by Bertucci et al, scientists took a listen under the surface to determine if, similar to their terrestrial counterparts, the sounds made on the reefs would give a glimpse into their complexity and overall health. This work paid particular attention to the difference in soundscape between Marine Protected Areas (MPAs) and non-Marine Protected Areas (nMPAs). MPAs, are areas in the ocean that have been specifically designated as in need of legal protection due to high levels of biodiversity, cultural significance, connectivity, or otherwise important functions. It has long been observed that protecting sensitive areas in the ocean prevents diversity loss, increases fish populations, and in general serves to make our oceans healthier for everyone who uses them.
Without getting too into the complex methods and scientific terminology that the article uses, the overall process is easy enough to understand. Researchers took two underwater sound recorders, placing one 10 meters down on the reef within a MPA, one on a corresponding nMPA and recorded sounds for 5 minutes every hour for 48 hours. They recorded day and night to determine if there was a difference between the daytime and the nighttime marine activity. The researchers found that the intensity of ambient sound on the reef, the sound pressure, was a direct indicator of living coral cover on the bottom of the reef. In other words, the noisier a reef, the more corals cover the bottom. This shouldn’t be a very surprising finding because we already know that corals provide essential habitat to a wide variety of marine species – the kind that would make noise underwater.
These results do have potentially useful impacts for Coral Restoration Foundation moving forward in our restoration efforts. Ultimately, we want to see the large-scale restoration of our coral reefs to their former beauty and incredible biodiversity, and this means using every trick in our book to ensure that goal is met. Here at Coral Restoration Foundation, we are taking an active approach to restoring our reefs and conserving our oceans by keeping up with all of the newest advances in understanding restoration best-practice, marine monitoring, and keys to sustainability. Every new method and tool brings us one step closer to restoring Florida’s reefs to their former glory by returning the corals, fish, and critters to their rightful homes.
“Coral reefs have their own wonderful soundscape, and you guessed it – the louder the better!”
Bertucci, Frédéric; Parmentier, Eric; Lecellier, Gaël; Hawkins, Anthony D.; Lecchini, David. “Acoustic indices provide information on the status of coral reefs: an example from Moorea Island in the South Pacific.” 2016
Skirble, Rosanne. “Undersea Soundscape Gives Insight Into Reef Health.” VOA News, Science & Technology. 2015.
“The Benefits of Marine Protected Areas.” Commonwealth Department of Environment and Heritage. Australia. 2003