By Dr. Doran Mason (NOAA Great Lakes Environmental Research Laboratory) and Felix Martinez (National Centers for Coastal Ocean Science)

University of Puerto Rico grad students servicing a hydrophone at the Weinberg site at La Parguera Natural Reserve on the southwest coast of Puerto Rico. Photo Credit: Rebecca Becicka, Ph.D. student at University of Puerto Rico, Mayagüez
Researchers at NOAA’s Great Lakes Environmental Research Laboratory (GLERL) are exploring the use of sound to monitor and assess the health of coastal ecosystems, most recently focusing on the soundscape created by Hurricanes Irma and Maria in Puerto Rico. In collaboration with the University of Puerto Rico at Mayagüez, Purdue University (a partner university in the Cooperative Institute for Great Lakes Research consortium), and the National Centers for Coastal Science (NCCOS), GLERL has launched a pilot study on developing the long-term use of soundscape. To implement this new approach to monitoring, hydrophones, an instrument in measuring sound, are used to track the response of ecosystems to natural (e.g., tropical storms) and human-induced (e.g., stressors such as excess nutrients, sedimentation, fishing pressure, climate change) disturbances.
In this pilot project, hydrophones have been in place for six months at three sites (see below for Google Earth Map of Magueyes Island, La Parguera, Puerto Rico) at La Parguera Natural Reserve on the southwest coast of Puerto Rico prior to and during the two category 4 hurricanes that pummeled the island. Miraculously, the recorders and data survived the storms and were recovered, providing us with a unique opportunity to listen to the hurricanes and to evaluate how quickly reefs recover from a natural disaster.
What is a soundscape? Soundscapes are created by the aggregation of sounds produced by living organisms (invertebrates, fish, marine mammals), non-biological natural sounds (waves, rain, movement of the earth), and sounds produced by humans (boats, coastal roads). Changes in the biological portion of soundscape can provide us with the quantitative data to assess the health of the ecosystem in response to natural and human-induced disturbance. Thus, our overall goal is to develop quantitative indices of coastal ecosystem health, based on the soundscape to assess the state of the environment, and to understand and predict changes, with application towards ecosystem restoration and conservation efforts. The utility of this approach is the use of a low-cost, remote autonomous technology that holds potential in expanding NOAA’s long-term observational capacity to monitor and assess coastal habitats.
Why GLERL? As part of a long history of monitoring and research in the Great Lakes, GLERL scientists have cultivated a unique expertise in the development of autonomous remote sensing technology. In the last two decades, Purdue University (a CIGLR partner) has been one of the leaders in the development of terrestrial soundscapes as a critical tool to monitor ecosystem change. More recently, interest has grown in expanding this approach into the aquatic realm. Building on our relationship with Purdue, GLERL and partners are well positioned to advance use of soundscape ecology to meet NOAA’s mission to protect, restore, and manage the use of coastal and ocean resources. In addition to the pilot study, GLERL is partnering with NCCOS to reach out to other NOAA Line Office programs in efforts to formalize the use of soundscapes within NOAA as a scientific program. For example, efforts are underway to plan an international workshop to establish the foundational principles and identify research and technology gaps for the use of soundscape ecology.
Why Puerto Rico? Original support for this pilot study came from a congressional allocation for enhancing relationships with the cooperative institutes for the benefit of coral reef restoration and conservation. Given the scientific knowledge accrued from NCCOS’ prior investments in La Parguera, GLERL and its NCCOS partner recognized that Puerto Rico would be a prime location to test and develop the use of soundscapes technology to track and quantify the health of coastal ecosystems.

Google Earth Map of Magueyes Island, La Parguera, Puerto Rico showing coral reef locations where the hydrophones were deployed at different depths: Weinberg (shelf-edge) – 75′; Media Luna (mid-shelf) – 45′; Pelotas (inner-shelf) – 35′. Provided by: Prof. Richard Appeldoorn, University of Puerto Rico, Mayagüez

Colleagues from Purdue University and University of Puerto Rico deploy Media Luna reef site hydrophone for the first time. Photo credit: Steve Ruberg, NOAA GLERL

View of La Parguera from Media Luna reef site. Photo credit: Steve Ruberg, NOAA GLERL