Profile Image

Bryan C Pijanowski

Forestry and Natural Resources 

  • Professor of Landscape and Soundscape Ecology
FORS Room 305
195 Marsteller Street
West Lafayette, IN 47907

 General Information

Soundscape Ecology and the Biodiversity Crisis

The current biodiversity crisis is our “silent” grand challenge that needs creative solutions.  As we entered the 21st century, our alteration of the planet resulted in the loss of plants, animals and microbes at unprecedented rates.  Feeding a planet of 9 billion people by 2050 will require us to ensure that the rest of the 11 million species also survive and flourish as we depend upon them to keep our ecosystems working properly.

There are three major dimensions to the biodiversity crisis.  The first is species loss.  Current estimates are that nearly 40% of the major vertebrate groups (e.g., amphibians, mammals) are in a threatened and endangered status.  Current extinction rates are close to those following the die off of the dinosaurs. Many animals help to maintain our crops, sustain ecosystem functioning like water purification, and provide essential functions (e.g., pollinators).  If they go, who, or what, does that work? The second dimension to the biodiversity crisis is reduced abundances.  So, for species that are still in existence, many of their numbers are in serious decline. This is especially true of animals that roam our expansive grasslands. The third dimension to the biodiversity crisis is the rampant expansion of invasive species which have been either purposely or accidentally introduced into ecosystems around the world.  These invasive species threaten the services (e.g., food production) of all ecosystems that we depend on.

How do we assess biodiversity trends so that we can make more informed decisions about natural resource management especially given our need to feed a much larger human population?  Few scientific techniques are available to monitor biodiversity. It is impractical to send scientists out around the world with clipboards and binoculars, especially to remote areas, to physically monitor all of life.  Satellites are improving our understanding of plant diversity and how they change around the world, but how do we monitor the animals?  Insects, fish, amphibians, reptiles, birds and mammals are difficult to detect.

Our work at Purdue’s Center for Global Soundscapes attempts to add a strong voice to the current biodiversity crisis so that it is no longer silent.  Through the use of acoustic sensors, AI (artificial intelligence) tools, and big data mining techniques, we seek to understand how humans impact biodiversity so that we can create a better future for all 11 million species while also improving human well-being. Our massive 4+ million audio recordings -- many made in exotic places around the world -- are being used to study biodiversity trends in the face of climate change, habitat alteration such as deforestation, mining, grazing, and noise. Recordings contain a mix of complex sounds, collectively called a soundscape, also contain the acoustic signatures of the geophysical environment as well as those sounds made by humans.  These acoustic signals give us measures also of climate dynamics and even human activities patterns (e.g., energy use).

Current projects include the following:

  • Assessment of coral reef recovery from hurricanes using continuous audio recordings in Puerto Rico
  • Measuring the impacts of livestock overgrazing in the steppe ecosystems of Mongolia
  • Quantifying the spatial autocorrelation of biological sounds in Bornean paleotropical rainforests
  • Determining the relationship between vegetation structural complexity and biological sound complexity in the neotropics of Costa Rica
  • Determining how coffee plantation management strategies affect biodiversity through soundscape characterization
  • The use of sound recordings to determine the breadth and variability of functional diversity
  • Using soundscapes to measure recovery of deserts to wildfire

Have time to help?  Join our mission and just listen.  Our Record the Earth citizen science platform enables you to record your own soundscape and to tell us how it affects you.  We are using that information to understand the acoustic link humans have to nature.  Think your birding skills are great?  We have online files for you to listen to and score at  These are used to build a massive database for our AI tools to probe and learn from. Give to our foundation the Natural Sounds Preservation Foundation to help us pay for batteries, hiking shoes, tents or more.

Facilities - Human-Environment Modeling and Analysis Lab, Spatial Data Analysis Lab 

Related Centers - Center for Global Soundscapes, Center for the Environment, Purdue Climate Change Research Center

Forestry and Natural Resources, 715 West State Street, West Lafayette, IN 47907-2061 USA, (765) 494-3590

© Purdue University | An equal access/equal opportunity university | Integrity Statement | USDA non-discrimination statement | Copyright Complaints | Maintained by Agricultural Communication

Trouble with this page? Disability-related accessibility issue? Please contact us at so we can help.

Sign In