Bats could help the development of AI robots

Rolf Müller – rolf.mueller@vt.edu
X (twitter): @UBDVTLab
Instagram: @ubdvtcenter
Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia, 24061, United States

Popular version of 4aAB7 – Of bats and robots
Presented at the 186th ASA Meeting
Read the abstract at https://eppro02.ativ.me/web/index.php?page=IntHtml&project=ASASPRING24&id=3678781

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

Given the ongoing revolution in AI, it may appear that all humanity can do now is wait for AI-powered robots to take over the world. However, while stringing together eloquently worded sentences is certainly impressive, AI is still far from dealing with many of the complexities of the real world. Besides serving the sinister goal of world-domination, robots that have the intelligence to accomplish demanding missions in complex environments could transform humanity’s ability to deal with fundamental key challenges to its survival, e.g., production of food and regrowable materials as well as maintaining healthy ecosystems.

To accomplish the goal of having a robot operate autonomously in complex real-world environments, a variety of methods have been developed – typically with mixed results at best. At the basis of these methods are usually two related concepts: The creation of a model for the geometry of an environment and the use of deterministic templates to identify objects. However, both approaches have already proven to be limited in their applicability, reliability, as well as due to their often prohibitively high computational cost.

Bats navigating dense vegetation – such as in rainforests of Southeast Asia, where our fieldwork is being carried out – may provide a promising alternative to the current approaches: The animals sense their environments through a small number of brief echoes to ultrasonic pulses. The comparatively large wavelengths of these pulses (millimeter to centimeter) combined with the fact that the ears of the bats fall not too far above from these wavelengths on the size scale condemns bat biosonar to poor angular resolution. This prevents the animals from resolving densely packed scatterers such as leave in a foliage. Hence, the echoes that bats navigating under such conditions have to deal with inputs that can be classified as “clutter”, i.e., signals that consists of contributions from many unresolvable scatterers that must be treated as random due to lack of knowledge. The nature of the clutter echoes makes it unlikely that bats having to deal with complex environments rely heavily on three-dimensional models of their surroundings and deterministic templates.

Hence, bats must have evolved sensing paradigms to ensure that the clutter echoes contain the relevant sensory information and that this information can be extracted. Coupling between sensing and actuation could very well play a critical role in this. Hence, robotics might be of pivotal importance in replicating the skills of bats in sensing and navigating their environments. Similarly, the deep-learning revolution could bring a previously unavailable ability to extract complex patterns from data to bear on the problem of extracting insight from clutter echoes. Taken together, insights from these approaches could lead to novel acoustics-based paradigms for obtaining relevant sensory information on complex environment in a direct and highly parsimonious manner. These approaches could then enable autonomous robots that can learn to navigate new environments in a fast and highly efficient manner and transform the use of autonomous systems in outdoor tasks.

batsBiomimetic robots designed to reproduce the (a) biosonar sensing and (b) flapping-flight capabilities of bats. Design renderings by Zhengsheng Lu (a) and Adam Carmody (b).

As pilot demonstration for this approach, we present a twin pair of bioinspired robots, one to mimic the biosonar sensing abilities of bats and the other to mimic the flapping flight of the animals. The biosonar robot has been used successfully to identify locations and find passageways in complex, natural environments. To accomplish this, the biomimetic sonar has been integrated with deep-learning analysis of clutter echoes. The flapping-flight line of biomimetic robots has just started to reproduce some of the many degrees of freedom in the wing kinematics of bats. Ultimately, the two robots are to be integrated into a single system to investigate the coupling of biosonar sensing and flight.

New scientific tools help national parks learn more about wildlife and natural sounds

Cathleen Balantic – cathleen_balantic@nps.gov

Biologist, National Park Service, Natural Sounds and Night Skies Division
1201 Oakridge Drive Suite 100
Fort Collins, CO, 80524, United States

Popular version of 2aAB5 – From sounds to science on public lands: using emerging tools in terrestrial bioacoustics to understand national park soundscapes
Presented at the 186th ASA Meeting
Read the abstract at https://eppro02.ativ.me/web/index.php?page=IntHtml&project=ASASPRING24&id=3673733

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

In recent decades, audio recordings have helped scientists learn more about wildlife. Natural sounds help answer questions such as: which animals are present or absent from the environment? When do frogs and birds start calling in the spring? How are wildlife reacting to something humans are doing on a landscape?

As audio recordings have become less expensive and easier to collect, scientists can rapidly amass thousands of hours of data. To absorb this volume of data, instead of listening ourselves, we create automated detectors to find animal sounds in the recordings. However, it is a daunting and time-consuming task to create detectors for a diversity of species, habitats, and types of research.

This is a familiar challenge to researchers in the National Park Service Natural Sounds and Night Skies Division. Our division is a national service office that provides scientific expertise and specialized technical assistance to parks, and we need to be prepared to help any of the 400+ national parks that have questions about bioacoustics. Each park has distinct research questions, varied habitats, and different wildlife (Fig. 1, Sound Clip 1).

national parks

Figure 1. Varied Thrush at Glacier Bay National Park and Preserve in 2015. Image courtesy of the National Park Service.

Several bird species vocalize at an acoustic monitoring station at Glacier Bay National Park and Preserve, including Pacific Wren, American Robin, and Varied Thrush. This example was recorded on June 13, 2017, at 3:22am local time. Audio recording courtesy of the National Park Service.

As more parks collect audio data to answer pressing research and management questions, building a unique automated detector for a single park project is no longer tenable. Instead, we are adopting emerging technology like BirdNET, a machine learning model trained on thousands of species worldwide (not just birds!). BirdNET provides us with more capacity. Instead of painstakingly building one detector for one project, BirdNET enables us to answer questions across multiple national parks.

But emerging technology poses more questions, too. How do we access these tools? What are the best practices for analyzing and interpreting outputs? How do we adapt new methods to answer many diverse park questions? We don’t all have the answers yet, but now we have code and workflows that help us process terabytes of audio, wrangle millions of rows of output, and produce plots to visualize and explore the data.

We are learning even more by collaborating with other scientists and land managers. So far, we’re exploring avian soundscapes at Glacier Bay National Park and Preserve across a decade of monitoring – from when birds are most vocally active during the spring (Fig.2), to when they are most active during the dawn chorus (Fig. 3). We are learning more about wildlife in the Chihuahuan Desert, wood frogs in Alaska, and how birds respond to simulated beaver structures at Rocky Mountain National Park.

The information we provide and interpret from audio data helps parks understand more about wildlife and actions to protect park resources. Translating huge piles of raw audio data into research insights is still a challenging task, but emerging tools are making it easier.

 

Figure 2. Heat map of BirdNET detection volume for selected focal species at Glacier Bay National Park and Preserve. (a) Hermit Thrush, (b) Pacific-slope Flycatcher, (c) Pacific Wren, (d) Ruby-crowned Kinglet, (e) Townsend’s Warbler, and (f) Varied Thrush. Dates ranging in color from purple to yellow indicate increasing numbers of detections. Dates colored gray had zero detections. White areas show dates where no recordings were collected. Image courtesy of the National Park Service.

 

Figure 3. Heat map of Varied Thrush detections across date and time of day at Glacier Bay National Park and Preserve. Timesteps ranging in color from purple to yellow indicate increasing numbers of detections. Timesteps colored gray had zero detections. White areas show times when no recordings were collected. Audio recordings were scheduled based on sunrise times. Image courtesy of the National Park Service.

What fish species are singing along the southern Australian continental shelf?

Lauren Amy Hawkins – laurenhawkins799@gmail.com

Centre for Marine Science and Technology, Curtin University, Bentley, Western Australia, 6102, Australia

Benjamin Saunders
School of Molecular and Life Sciences
Curtin University
Bentley, Western Australia, Australia

Christine Erbe, Iain Parnum, Chong Wei, and Robert McCauley
Centre for Marine Science and Technology
Curtin University
Bentley, Western Australia, Australia

Popular version of 5aAB6 – The search to identify the fish species chorusing along the southern Australian continental shelf
Presented at the 185 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0023649

Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.

Unknown fish species are singing in large aggregations along almost the entire southern Australian continental shelf on a daily basis, yet we still have little idea of what species these fish are or what this means to them. These singing aggregations are known as fish choruses, they occur when many individuals call continuously for a prolonged period, producing a cacophony of sound that can be detected kilometres away. It is difficult to identify fish species that chorus in offshore marine environments. The current scientific understanding of the sound-producing abilities of all fish species is limited and offshore marine environments are challenging to access. This project aimed to undertake a pilot study which attempted to identify the source species of three fish chorus types (shown below) detected along the southern Australian continental shelf off Bremer Bay in Western Australia from previously collected acoustic recordings.

Each fish chorus type occurred over the hours of sunset, dominating the soundscape within unique frequency bands. Have a listen to the audio file below to get a feeling for how noisy the waters off Bremer Bay become as the sun goes down and the fish start singing. The activity of each fish chorus type changed over time, indicating seasonality in presence and intensity. Chorus I and II demonstrated a peak in calling presence and intensity over late winter to early summer, while Chorus III demonstrated peak calling over late winter to late spring. This informed the sampling methodology of the pilot study, and in December 2019, underwater acoustic recorders and unbaited video recorders were deployed simultaneously on the seafloor along the continental shelf off Bremer Bay to attempt to collect evidence of any large aggregations of fish species present during the production of the fish choruses. Chorus I and the start of Chorus II were detected on the acoustic recordings, corresponding with video recordings of large aggregations of Red Snapper (Centroberyx gerrardi) and Deep Sea Perch (Nemadactylus macropterus). A spectrogram of the acoustic recordings and snapshots from the corresponding underwater video recordings are shown below.

Click here to play audio

The presence of large aggregations of Red Snapper present while Chorus I was also present was of particular interest to the authors. Previous dissections of this species had revealed that Red Snapper possessed anatomical features that could support sound production through the vibration of their swimbladder using specialised muscles. To explore this further, computerized tomography (CT) scans of several Red Snapper specimens were undertaken. We are currently undertaking 3D modelling of the sound-producing mechanisms of this species to compute the resonance frequency of the fish to better understand if this species could be producing Chorus I.

Listening to fish choruses can tell us about where these fish live, what habitats they use, their spawning behaviour, their feeding behaviour, can indicate their biodiversity, and in certain circumstances, can determine the local abundance of a fish population. For this information to be applied to marine spatial planning and fish species management, it is necessary to identify which fish species are producing these choruses. This pilot study was the first step in an attempt to develop an effective methodology that could be used to address the challenging task of identifying the source species of fish choruses present in offshore environments. We recommend that future studies take an integrated approach to species identification, including the use of arrays of hydrophones paired with underwater video recorders.

Listening to the Largest Tree on Earth #ASA184

Listening to the Largest Tree on Earth #ASA184

Hydrophones record the sounds of the massive Pando aspen grove, from its leaves to its roots.

Media Contact:
Ashley Piccone
AIP Media
301-209-3090
media@aip.org

CHICAGO, May 10, 2023 – Spread across 106 acres in southcentral Utah, the Pando aspen grove resembles a forest but is actually a single organism with more than 47,000 genetically identical aspen stems connected at the root. Pando is the world’s largest tree by weight and land mass. Research suggests Pando has been regenerating for 9,000 years, making it one of the oldest organisms on Earth.

The Pando aspen grove in southcentral Utah after a thunderstorm. Credit: Jeff Rice. Copyright 2023. All Rights Reserved.

As part of the 184th Meeting of the Acoustical Society of America, Jeff Rice and Lance Oditt will describe their work to reveal a unique acoustic portrait of this botanical wonder. Their presentation, “Beneath the tree: The sounds of a trembling giant,” will take place Wednesday, May 10, at 10:30 a.m. Eastern U.S. in the Great America 1/2 room, as part of the meeting running May 8-12 at the Chicago Marriott Downtown Magnificent Mile Hotel.

“Pando challenges our basic understanding of the world,” said presenter Jeff Rice, a sound artist from Seattle. “The idea that this giant forest could be a single organism defies our concept of the individual. Its vastness humbles our sense of space.”

After recording Pando’s leaves for The New York Times Magazine’s special issue “Listen to the World” in 2018, Rice returned in July 2022 as an artist-in-residence for the nonprofit group, Friends of Pando, which Oditt founded in 2019. Rice used a variety of microphones to record Pando’s leaves, birds, and weather.

“The sounds are beautiful and interesting, but from a practical standpoint, natural sounds can be used to document the health of an environment,” he said. “They are a record of the local biodiversity, and they provide a baseline that can be measured against environmental change.”

Rice was particularly captivated by the sound of vibrations passing through the tree during a windstorm. He wanted to see if they could record the sound of Pando’s root system, which can reach depths of 90 feet by some accounts. Oditt, executive director of Friends of Pando, identified several potential recording locations below the surface.

“Hydrophones don’t just need water to work,” said Rice. “They can pick up vibrations from surfaces like roots as well, and when I put on my headphones, I was instantly surprised. Something was happening. There was a faint sound.”

That sound is not conclusively from Pando’s root system. But a handful of experiments support the idea. Rice and Oditt were able to show that vibrations can pass from tree to tree through the ground. When they banged lightly on a branch 90 feet away, the hydrophone registered with a low thump. Rice compares this to the classic tin can telephone.

“It’s similar to two cans connected by a string,” he said. “Except there are 47,000 cans connected by a huge root system.”

A similar phenomenon occurred during a thunderstorm. As leaves moved more intensely in the wind, the signal recorded by the hydrophone also increased.

“The findings are tantalizing. While it started as art, we see enormous potential for use in science. Wind, converted to vibration (sound) and traveling the root system, could also reveal the inner workings of Pando’s vast hidden hydraulic system in a nondestructive manner,” said Oditt. “Friends of Pando plans to use the data gathered as the basis for additional studies on water movement, how branch arrays are related to one another, insect colonies, and root depth, all of which we know little about today.”

———————– MORE MEETING INFORMATION ———————–
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eppro02.ativ.me/web/planner.php?id=ASASPRING23&proof=true

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are 300 to 500 word summaries of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org.  For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Warmer Climate Could Cause Puerto Rico’s Frogs to Croak #ASA184

Warmer Climate Could Cause Puerto Rico’s Frogs to Croak #ASA184

Rising temperatures leave their mark in the distinctive calls of the coqui frog.

Media Contact:
Ashley Piccone
AIP Media
301-209-3090
media@aip.org

CHICAGO, May 8, 2023 – The coqui frog is one of Puerto Rico’s most iconic animals. It gets its name from its distinctive two-note call, “co-qui,” which can be heard throughout the island every night. The males of the species produce these calls to mark their territory and ward away rivals, but scientists can also use them to study the changing climate.

Peter Narins of the University of California, Los Angeles will describe changes in the calls of the coqui frog over a 23-year period in his talk, “Climate change drives frog call change in Puerto Rico: Predictions and implications.” The presentation will take place Monday, May 8, at 2:40 p.m. Eastern U.S. in room Chicago F/G, as part of the 184th Meeting of the Acoustical Society of America running May 8-12 at the Chicago Marriott Downtown Magnificent Mile Hotel.

Male coqui calling in El Yunque, Puerto Rico. Credit: K. Wells

Over two decades ago, Narins recorded the sounds of the coqui frog along the slopes of Puerto Rico’s El Yunque Peak. His team discovered the calls changed based on elevation. Like all amphibians, coqui frogs are highly sensitive to changes in temperature. On cold mountain peaks, the frogs grow larger than in warmer valleys, and this size discrepancy is reflected in their calls.

“Coqui that produced short, high-pitched calls at high rates lived near the base of the mountain, while the calls of animals living near the mountain’s peak were longer, lower-pitched, and repeated less frequently,” said Narins.

Upon returning to the mountain two decades later, Narins and a team including colleague Sebastiaan Meenderink discovered that every frog call had grown higher in pitch.

“In order to record a call with certain characteristics we had to move to a slightly higher altitude,” said Meenderink. “It was as if all the animals had moved up the mountain.”

This mini-migration corresponds with the temperature shift induced by climate change and foreshadows a dire future for the coqui. As temperatures continue to rise, the frogs will continue to retreat up the mountain until they run out of room.

“For now, the consequences are not dire,” said Meenderink. “A barely perceptible change in frog body size and call has little impact on the environment. However, if left unabated, the temperature increase will eventually cause a collapse of the coqui population, which will be catastrophic for the Puerto Rican ecosystem.”

———————– MORE MEETING INFORMATION ———————–
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eppro02.ativ.me/web/planner.php?id=ASASPRING23&proof=true

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are 300 to 500 word summaries of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org.  For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Behaviors produced by a variety of sounds among eagles: A study with survival implications

JoAnn McGee – mcgeej@umn.edu

University of Minnesota
75 East River Parkway
Minneapolis, MN 55455
United States

Christopher Feist
Christopher Milliren
Lori Arent
Julia B. Ponder
Peggy Nelson
Edward J. Walsh

Popular version of 3aABb4 – Behavioral responses of bald eagles (Haliaeetus leucocephalus) to acoustic stimuli in a laboratory setting
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018607
Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.

The ultimate goal of this project is to protect eagles by discouraging these charismatic birds from entering the airspace of wind energy facilities. The specific question under consideration centers on whether or not an acoustic cue, a sound, can be used for that purpose, to steer eagles away from harm’s way. Our specific goal in this particular study was to take the next step along our overall research path and determine if behaviors of bald eagles in particular were affected by different sound stimuli in a controlled laboratory environment.

Perhaps to be expected, behavioral responses varied significantly. Some birds explored their immediate airspace avidly, while others exhibited a more restrained set of behavioral responses to sound stimulation.

To get a feeling for the task, consider the reaction of this eagle to a sound stimulus in a quiet laboratory setting .

To collect these data, a bird was placed in a sound-damped room and the experiment was conducted from a control center just outside the exposure space. Birds were videotaped as sounds were delivered to one of two speakers and a group of unbiased judges was asked to determine (1) whether the bird responded to the sound based on its behavior, (2) to qualitatively assess the strength of the response, and (3) to identify the behaviors associated with the response. Twelve sounds were tested and judges were instructed to observe the eagle during a specified time window without knowing which sound, if any, had been played. Spectrograms of the sounds tested are shown in the figure.


By far the most common response was an attempt to localize the sound source based on head turning toward a speaker, although birds also frequently tilted their heads in response to stimuli. Females were slightly more responsive to sound stimuli than males, and not surprisingly, stimuli that elicited a higher number of responses also elicited stronger or more evident responses. Complex and natural sounds, for example, sounds produced by eagles, eaglets and pesky mobbing crow sounds, elicited more and stronger responses than man-made stimuli. Generally, bald eagles were fairly accurate in locating the direction that the sound originated, and, as before, females performed better than males.

The results from this study provide a critical step in an effort to protect eagles as we move away from the use of fossil fuels and rely more on wind power. We come away from this study with a better understanding of the types of sound signals that elicit more and stronger responses in bald eagles, and with the confidence that we will be able to objectively assess behavioral responses in more natural settings. We now know what these magnificent birds can hear, and we know that certain sound stimuli are more effective than others in evoking behavioral responses, taking us one step closer to our ultimate goal, to save bald eagles from undesirable outcomes and to give wind facility developers the tools needed to manage their facilities in an even more eco-friendly manner.