As new technologies supercharge the field of bioacoustics, researchers can better listen to environmental changes \u2014 and use the information to guide conservation efforts.<\/p>\n
After Hurricane Maria tore through Puerto Rico in 2017, photos showed downed trees, flooded communities, collapsed homes and buckled roads. But what did the aftermath\u00a0sound<\/em> like?<\/p>\n Ben Gottesman, now a member of the\u00a0K. Lisa Yang Center for Conservation Bioacoustics<\/a>\u00a0at the Cornell Lab, was part of a team of researchers from Purdue University\u2019s Center for Global Soundscapes and the National Oceanic and Atmospheric Administration that monitored changes in the soundscape on land and in the water to better understand how birds, bugs, shrimp, fish and other animals responded to the disturbance.<\/p>\n The work is part of the growing field of bioacoustics, which combines biology and acoustics to gain insight into the world around us by listening. It\u2019s become a potent tool for research and conservation as recording devices have improved and gotten cheaper \u2014 and as machine learning can crunch massive amounts of data. That\u2019s helped researchers from the Yang Center and other institutions better understand everything from right whales in the North Atlantic to tiny katydids in the canopies of tropical forests.<\/p>\n The Revelator<\/em>\u00a0spoke to\u00a0Gottesman<\/a>\u00a0about which animals bioacoustics can help us study, how researchers sort through millions of hours of recordings, and why new technologies aren\u2019t just for experts.<\/p>\n You did your Ph.D. in soundscape ecology. What is that?<\/strong><\/p>\n It\u2019s the study of sound in our environment and trying to understand places through how they sound. That can be learning about biodiversity through recording and analyzing the sounds from different ecosystems or doing a more comparative approach where you\u2019re trying to understand what makes this tropical forest sound the way it does. What are all the sounds in a given place? How do they vary over space and time?<\/p>\n I think a lot of places have something to tell us about either environmental issues or interesting behaviors.<\/p>\n What can sound tell us about a changing world?<\/strong><\/p>\n It can tell us a lot. You can look over decades where you see ocean noise levels doubling every 10 years, and that corresponds with this increase in shipping. These long-term anthropogenic stressors, a lot of them are tied to changes acoustically.<\/p>\n Likewise long-term changes in biodiversity also convey acoustically. There was a big study led by the Cornell Lab that found that\u00a03 billion birds were lost<\/a>\u00a0[in North America] since the 1970s. I imagine that that\u2019s led to a desaturation of dawn choruses, which is a peak period of biophony, or sounds produced by animals. Biodiversity loss carries an acoustic signature in many places with a desaturating soundscape or a loss of dynamics.<\/p>\n Then over shorter time scales, you have impacts such as logging or mining that can also have a large effect on the soundscape as well. Through that we can learn about changes to the animal communities.<\/p>\n In my work I studied the impact of Hurricane Maria. It\u2019s not a direct human-caused disturbance, but there was a marked reduction in dawn chorus periods where usually you have a whole vibrant mix of birds that are singing. That declined sharply after the storm, likely signifying the initial damage wrought by this intense hurricane. The insect choruses were depleted as well.<\/p>\n But then we had these hydrophones recording just a few miles away, and there was very little change. The fish choruses were present during the night just like before. The snapping shrimp were still snapping away at very similar levels. That was one example early on that gave me this firsthand experience learning about how soundscapes can convey ecological changes.<\/p>\n People are trying to use passive acoustic monitoring as a tool to understand the degree to which places are being affected by all kinds of different stressors. But it can also [be used to understand] restoration. Acoustics is a really great way to understand what species are profiting from such restoration, how long it takes for places to bounce back, and what restoration methods are most effective given your management goals.\u00a0My colleague Vijay Ramesh just\u00a0published a paper<\/a>\u00a0about understanding the effectiveness of restoration using passive acoustic monitoring.<\/p>\n What kinds of tools are used for this?<\/strong><\/p>\n There are passive recording technologies, and those are typically recorders with battery and storage that you can leave outdoors. The SwiftOnes that we make at the Yang Center can record for more than a month continuously. Underwater, the tech is more advanced. We\u2019ve developed underwater recorders called Rockhoppers that can record for more than a year straight as deep as 1,000 meters.<\/p>\n Cornell Researcher Builds Groundbreaking Machine Learning Toolkit For Bioacoustics | The Cornell Daily Sun https:\/\/t.co\/xNQM497iOP<\/a><\/p>\n \u2014 Yang Center for Conservation Bioacoustics (@CornellSounds) November 10, 2022<\/a><\/p><\/blockquote>\n\n