Live for Listening:

Underwater Sound in National Marine Sanctuaries

By Leila Hatch


April 2022

NOAA, the U.S. Navy, and partners have launched a new web portal that allows users to learn about and listen to underwater sounds throughout the National Marine Sanctuary System. As the sanctuary system celebrates its 50th anniversary, this resource provides another way to experience the wonders of America’s underwater treasures without getting wet.

The SanctSound portal invites the public to explore the results of a three-year project involving over 50 scientists from 20 institutions from all over the country who collected and analyzed underwater recordings from seven national marine sanctuaries and one marine national monument, including waters off Hawaii and the East and West coasts.

a map showing the listening stations throughout the United States
Underwater sound was recorded using temporary bottom-mounted sensors as well as autonomous underwater vehicles in Stellwagen Bank, Gray’s Reef, Florida Keys, Olympic Coast, Monterey Bay, Channel Islands, and Hawaiian Islands Humpback Whale national marine sanctuaries and Papahānaumokuākea Marine National Monument. Image: NOAA

SanctSound recordings include sounds made by marine animals and physical processes, like wind and waves, as well as sounds produced by human activities. Invertebrates (like snapping shrimp), fish, whales, vessels, fishing activities, and sonars used in military training are a few of the expected and relatively well-characterized sources of sound recorded throughout the project.

a schematic of a coastline above and below the water showing silhouettes of various wildlife as well as ships, fishing vessels, storm clouds, and other sources of sound
In the web portal, sounds recorded in each sanctuary’s soundscape can be explored through interactive underwater scenes that allow users to hear sounds and understand when and where they were present. Image: Aline Design for NOAA

The web portal allows users to explore the sonic features of each sanctuary, and to make comparisons among locations to better understand how similar or different they are from each other. To do this, the portal describes sound information from each of its 30 recording locations in a comparable way. SanctSound generated 300 terabytes of data, all of which are accessible to download from the NOAA National Centers for Environmental Information (NCEI) Passive Acoustic Archive. Standard measurements extracted from these recordings are also archived at NCEI and made accessible through the web portal, which is hosted by the U.S. Integrated Ocean Observing System.

Sound is critical for the survival of many marine animals because it’s a primary means of communication, orientation and navigation, finding food, avoiding predators, and mate selection. As such, human activities that produce sound underwater have the potential to negatively impact animals by reducing their ability to hear prey, predators, and each other. In other cases, loud sounds can cause physical injury or behavioral reactions.

an animation showing the overlap of different sounds recorded from different sound sources underwater
This animation shows how the hearing abilities of animals focused on in the project (green bars) overlap with the types of physical sounds (purple) and human-made sounds (orange) that we recorded. There are more sound-producing human activities and more sanctuary animals that use or produce sound than are depicted here. The yellow bar indicates the hearing range of humans in air as well as the range of frequencies that were recorded by SanctSound hydrophones. Animation: Aline Design for NOAA.

Underwater sounds are helping sanctuaries better protect these special places. Education and outreach products accessible through the web portal show how this new information is being used at individual sanctuaries and across the system. As part of the National Marine Sanctuary Systems’s 50th Anniversary celebration, an Ocean Sound and Impact of Noise Resource Collection was created, which allows educators to explore a collection of NOAA videos, lesson plans, webinars, web stories, virtual reality, and more focused on this topic. A webinar tutorial for the SanctSound web portal will be held on May 17, 2022 from 2-3 p.m. ET.

Register for Webinar
Visit SanctSound Portal


Grab some headphones, turn up the volume on your phone or computer, and dive into the underwater sounds of your sanctuary system!

Dr. Leila Hatch is a research ecologist with the Office of National Marine Sanctuaries' Science and Heritage Division and co-lead of the SanctSound project