Why Do Brown Bats Stop Feeding During Fireworks? #ASA190

What acoustics can teach us about animal behaviors during disruptive events like firework shows.

PHILADELPHIA, May 12, 2026 — Firework shows are controversial in this day and age. While beautiful, fireworks are loud, bright, and smoky, and they can be dangerous to the surrounding environment, releasing contaminants into the air and frightening both pets and wildlife alike.

Luckily, cities across the country are taking initiative to explore the impact of fireworks on residents and wildlife. In October 2025, the City of Capitola, California, and Integral Consulting conducted a study to determine the effect of their annual firework show on the surrounding animal population in the Monterey Bay Marine Sanctuary.

Integral Consulting’s Kerri Seger and Greg Cotten used the opportunity to observe how the fireworks impacted the feeding patterns of brown bats. They will present their findings Tuesday, May 12, at 10:15 a.m. ET as part of the 190th Meeting of the Acoustical Society of America, running May 11-15.

Person in red jacket views off image through a thermal scope at night with fireworks in background.

Photos from the October firework show in Capitola, California. Researcher Greg Cotten views the bats through a thermal scope (right). Credit: Amy Howk, Integral Consulting

Five days before the Capitola firework show, Cotten set up a microphone to record a normal night of bat activity, which could serve as a baseline. From data recorded the same night as the fireworks display, they identified bat behaviors based on the echolocation calls they heard: Some sounds corresponded to searching behaviors, others to food capture behavior.

On the night of the 31-minute firework show, Seger and Cotten recorded the bats for half an hour before the show, during the show, and half an hour afterward. They noticed that the bats were searching for and catching food steadily before the show, but during the fireworks, they were unsuccessful in catching any prey, despite searching.

“There is a measurable effect of the fireworks’ noise and/or lights on bats’ feeding, showing that bats can’t exactly eat dinner in peace while they are happening,” Seger said.

Then, after the show ended, the bats returned quickly to resume hunting but searching and catching were greatly reduced from their pre-show efforts. Cotten wondered if this result might be because of a “moth to a flame” effect.

“This phrase originated from Greg’s interpretation of me explaining what I heard in the data after my first listen,” Seger said.
The quick return to feeding could have been influenced by the bats’ natural prey — insects and moths — flocking to the bright lights of the fireworks, but it could also be totally unrelated to the availability of the food, instead caused by the bats feeling safer to return to a quiet area.

Seger said that these theories will require more testing beyond acoustics — for instance, directional microphones would help determine the numbers and directions of the bats and their prey, giving insight into their attraction to — or repulsion from — the explosions.

Seger believes that this work has the chance to influence firework policy in the city of Capitola.

“The city funded the study because they were interested in effects to wildlife from their fireworks show,” Seger said. “I suspect they will take the results seriously and have a concerted discussion about what they might or might not decide to permit in the future.”

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For more information:
AIP Media
1 301.209.3090
media@aip.org

Main Meeting Website: https://acousticalsociety.org/philadelphia/
Technical Program: https://eppro01.ativ.me/web/planner.php?id=ASASPRING2026

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 summaries (300-500 words) 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 the in-person conference at the Philadelphia Marriott Downtown for credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting and/or 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 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/.

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The Birds and the Babies: Humans and Zebra Finches Have a Similar Technique for Learning to Speak #ASA190

Humans and zebra finches both rely on caregiver reinforcement to learn complex vocalizations.

PHILADELPHIA, May 11, 2026 — We are all born completely helpless, with little of the knowledge and skills we will need to survive as adults. Even our ability to communicate is almost entirely learned from our parents or caregivers.

Some animals are the same. Zebra finches, in particular, are so similar to humans in how they learn to communicate that researchers often study them to better understand how we develop language.

To help answer these questions, Steven Elmlinger, from Princeton University, will present his research on early vocalizations in both human infants and zebra finches Monday, May 11, at 1 p.m. ET as part of the 190th Meeting of the Acoustical Society of America, running May 11-15.

A small finch with gray and orange feathers perches on a wooden bar, looking at an image of a small finch in a cage.

Since zebra finches are similar to humans in how they learn to communicate, researchers can use them as a model for infant language development. Credit: Michael H. Goldstein

Elmlinger studies vocal learning, piecing together how individuals develop and change their vocalizations to interact with others. He conducted three studies, two with human infants and one with finches, to understand how immature babbling transitions into adultlike speech.

In the first experiment, he observed infants interacting with their caregivers, noting that adults respond more to sequential vocalizations comprising multiple syllables than single syllable vocalizations. In the second study, he observed 30 infants across a period of several months to determine the role that these caregivers play in helping infants learn sequential vocalizations.

“We might assume that early learning of vocal sequences is primarily driven by motor practice,” said Elmlinger. “Prior research suggests social feedback guides infants’ vocal advances at the level of individual syllables. Here we wanted to know if social feedback also influences infants’ vocal sequence development.”

In this study, he and his colleagues found that caregiver responses to sequential vocalizations significantly increased the rate at which infants learned to produce those sequences. By encouraging complex vocalizations, caregivers could help their children learn faster.

In the third study, Elmlinger repeated this experiment with zebra finches, with the same finding. Like humans, zebra finches use social feedback to teach their young.

“Taken together, our results suggest that not only do both humans and zebra finches use social feedback to guide advances in the acoustics of their vocal repertoire, but their social environment also guides low-level temporal foundations of their vocal communication,” said Elmlinger.

When it comes to language learning, humans are not as unique as we once thought. At least one other species learns to vocalize in the same way we do, and there may be others awaiting discovery.

“I would love to collaborate with new-world monkey, cetacean, and bat scientists,” said Elmlinger. “There are good hints that at least some of these animals should show socially guided vocal learning as well — perhaps it is not rare, just understudied.”

###

For more information:
AIP Media
1 301.209.3090
media@aip.org

Main Meeting Website: https://acousticalsociety.org/philadelphia/
Technical Program: https://eppro01.ativ.me/web/planner.php?id=ASASPRING2026

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 summaries (300-500 words) 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 the in-person conference at the Philadelphia Marriott Downtown for credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting and/or 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 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/.

More Press Releases

Do short-tailed fruit bats suffer hearing damage after noise exposure?

Keegan Eveland1 – kevelan1@jhu.edu
Bluesky: keeganeveland
Instagram: @keveland3

Capshaw G.1,2*
Lauer, A. 2,3,4
Moss, C.F.1,3,5,6

  1. Department of Psychological and Brain Sciences
    Johns Hopkins University
    Baltimore, MD, 21218
  2. Department of Otolaryngology-Head and Neck Surgery
    Johns Hopkins University School of Medicine
    Baltimore, MD, 21205
  3. The Solomon H. Snyder Department of Neuroscience
    Johns Hopkins University School of Medicine
    Baltimore, MD, 21205
  4. Center for Functional Anatomy and Evolution
    Johns Hopkins University School of Medicine
    Baltimore, MD, 21205
  5. Department of Mechanical Engineering
    Whiting School of Engineering
    Johns Hopkins University
    Baltimore, MD, 21218
  6. Kavli Neuroscience Discovery Institute
    Johns Hopkins University
    Baltimore, MD, 21218

*Co-first author

Popular version of 2aAB8 – Noise-induced hearing loss susceptibility in the short-tailed fruit bat (Carollia perspicillata)
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/index.php?page=Session&project=ASASPRING2026&id=4082866

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

Hearing is crucial to many animal species that use sound to navigate, communicate, and avoid predators. Despite its importance, hearing in many animals is damaged by exposure to loud sounds. One exception is the echolocating bat, an animal that navigates in the dark using sound alone. While some vertebrates like fish and birds can regenerate the sensory cells that support hearing, mammals cannot, and hearing loss, caused by aging and exposure to loud noise, is common among mammals. This is what makes bats an intriguing case: bats can emit extremely loud ultrasonic calls (110 – 140 dB), the equivalent of a rock concert, yet some species show exceptional resistance to both age-related and noise-induced hearing loss.

However, not all bats are equally resistant to hearing loss; the ability to maintain hearing after noise exposure and into old age appears to reflect the degree of reliance on hearing for survival. For example, the big brown bat (Eptesicus fuscus), uses its hearing to hunt insects and is more resistant to both age-related and noise-induced hearing loss than the Egyptian fruit bat (Rousettus aegyptiacus), a frugivorous species that relies more heavily on vision for navigation and loses its hearing with age. This raises the question: What mechanisms make some bat species more resistant to hearing loss than others?

In this study, we examined noise susceptibility in the short-tailed fruit bat (Carollia perspicillata), which represents an interesting middle ground between these two species. Like the big brown bat, short-tailed fruit bats rely primarily on echolocation for navigation. However, like the Egyptian fruit bat, it feeds mainly on fruit and can supplement echolocation with other senses such as smell during foraging.

We hypothesize that short-tailed fruit bats maintain their hearing sensitivity even after exposure to loud noise, given their reliance on echolocation for navigation. To test this, we measured the bats’ hearing before and after one hour of exposure to intensely loud, 110 dB noise. We used two complementary methods: auditory brainstem responses, which assess auditory nerve and brainstem responses to sound, and otoacoustic emissions, which evaluate the functionality of the sensory cells that support cochlear amplification in the inner ear.

Our preliminary results show no long-term hearing damage following noise exposure, suggesting that short-tailed fruit bats possess protective mechanisms to preserve their most critical sense. These findings strengthen evidence that echolocation-dependent bats protect their hearing against noise damage better than those that primarily rely on other senses (such as vision). Understanding the biological mechanisms underlying this protection could have implications beyond bats and may reveal new strategies for preventing noise-induced hearing loss in other species.

 

Comparison of sonar reliance and hearing loss susceptibility among Egyptian fruit bats, short-tailed fruit bats, and big brown bats.

Listening in on the Conversations of Coyotes

Jennifer Schneider – jschneider@lcc.lt

LCC International University
Kretingos 36, KLAIPEDA
KLAIPEDA M., LT-92307
Lithuania

Dustin H. Ranglack
USDA APHIS WS National Wildlife Research Center
Utah Field Station

Popular version of 2pABa2 – A Comparison of the Squeaking Vocalizations of North American Wild Canids
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/planner.php?id=ASASPRING2026

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

The Question: Do Coyotes Squeak like Wolves Squeak?
We are all familiar with howls, but how many of us have heard a wolf or a coyote squeak? Squeaks are easy to miss for a number of reasons: one has to be in close proximity to hear them, animals behave differently when humans are around, and squeaks are easy to mistake for birdsong. Wild canids live in family groups and need to communicate during face-to-face interactions. Both gray (Canis lupus) and red wolves (Canis rufus) produce strings of short, quiet, high-frequency squeaks in a variety of friendly contexts. Yet, despite coyotes’ (Canis latrans) close relationship with wolves, this study is the first to systematically examine coyote squeaking vocalizations.

Video Credit: US Department of Agriculture. The male (closest coyote) squeaks several times, followed by the female. The male squeaks again when approaching the camera.

The Setup: Meeting the New Neighbors
To determine whether coyotes squeak we created a social situation to encourage interaction between bonded coyote pairs and their neighbors at the USDA Predator Research Station in Millville, Utah. Three pairs of coyotes were moved into adjacent enclosures and recorded using camera traps and continuous audio recordings. The observations reported here include the first 3.5 hours after release, as the animals explored their new enclosures and interacted through the fence with their neighbors.

Video Credit: US Department of Agriculture. Four coyotes vocalizing at the intersection between enclosures.

The Comparison: How Similar are Coyote Squeaks to Wolf Squeaks?
Coyote squeaks shared many similarities with wolf squeaks:

  • The number of squeaks per vocalization varied greatly (1 – >30).
  • The frequency bandwidth within which coyotes squeaked (3.0-11.0 kHz) was broad, more similar to red wolves (2.7-9.5 kHz) than gray wolves (1.8-6.0 kHz).
  • Squeaks of all three species display a variety of contours, with flat or bump-like shapes being among the most common.
  • Coyote squeaks were shorter, but showed similar frequency ranges to those of gray wolves, and were longer with greater frequency ranges than those of red wolves.
  • Squeaks occur in prosocial contexts such as greeting, friendly approach, play, and during howling sessions.

Like red wolves, coyotes sometimes produced a second, lower-frequency component (0.5-1.6 kHz), or wuh, simultaneously with their squeaks, a phenomena knowns as biphonation. Since we used multiple recorders, we discovered that the wuh did not travel as far as the squeak (Fig. 1). Therefore, the message received by eavesdroppers will be different than the message received by coyotes in the immediate area.

Two spectrograms showing frequency patterns from 0 to 10kHz with distinct vertical bands and intensity variations in purple, red, and orange hues.

Figure 1. Spectogram of a squeak vocalization with biphonations recorded near the vocalizing coyote (top panel) and on the far side of the enclosure (lower panel). The high-frequency squeak was still audible on the far side of the enclosure while the low-frequency wuh was not. To listen click here.

Why it Matters
Coyotes and wolves, being predators, often viewed negatively by humans. However, these animals also mate for life, live in social groups, and even raise young together. Getting a more holistic understanding of the lives of these animals requires listening in on their intimate communication. Squeaking is ubiquitous across North American canid species, despite differences in social structure complexity. Identifying the importance of this vocalization is only the first step. While we can see that squeaking is affiliative in nature, we are still a long-way from unlocking the subtleties of meaning in individual utterances.

Manduca sexta Caterpillars Hear Using Hairs

Sara Aghazadeh – saghaza1@binghamton.edu
Instagram: @saraaghazadeh1016
Department of Mechanical Engineering
Binghamton University (SUNY)
Binghamton, NY, USA

Aishwarya Sriram – asriram@binghamton.edu
Instagram: @sriram.aishwarya
Department of Biological Sciences
Binghamton University (SUNY)
Binghamton, NY, USA

Prof. Carol Miles – cmiles@binghamton.edu
Department of Biological Sciences
Binghamton University (SUNY)
Binghamton, NY, USA

Prof. Ronald Miles – miles@binghamton.edu
Department of Mechanical Engineering
Binghamton University (SUNY)
Binghamton, NY, USA

Popular version of 4pABb3 – The ears of Manduca sexta caterpillars
Presented at the 189th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0041196

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

The aim of this research is to explore how insects perceive vibration and sound, ultimately mimic these biological strategies to advance the technology of MEMS microphones. Some insects have tympanal membranes for the detection of sound pressure. These include, for example, katydids and crickets that have tympanal membranes on their forelegs, and the fly, Ormia ochracea that has paired tympanal organs on its prothorax. Most insects and spiders that can hear sound use non-tympanal sensors, such as long hairs on bee and mosquito antennae, and slit sensilla hairs in spiders. We are looking at Manduca sexta, tobacco hornworm caterpillars, a common garden pest devouring tobacco plants. This caterpillar can be found devouring tomato plants in your vegetable garden. While it does respond to sound, it is not clear whether it hears by detecting air-borne sound pressure using a tympanal membrane, hears acoustic particle velocity through the use of sensory hairs, or hears through the detection of sound-induced substrate vibration.

In this study, the caterpillars’ behavioral responses to sound were examined using sounds at two different frequencies: a 150 Hz tone, and a 2000 Hz tone. Previous studies have found strong behavioral responses at 150 Hz in tuning curve experiments. By measuring the sound-induced motion of a thoracic hair using laser vibrometry, we have observed a natural resonance of the hair at 2000 Hz. While we don’t normally expect insect hairs to be effective sound detectors at such high frequencies, this observation motivates further examination to look for behavioral responses.

We monitored caterpillars’ behavioral responses to vibrations of the surface the caterpillars were standing on, and to air-borne sound while we recorded the amplitude of the surface vibration. The results revealed that the caterpillars were 10-100 times more responsive to airborne sound than sound-induced vibration of the surface detected by their feet; this confirms that they perceive airborne sound. Our results show that they can hear airborne sound at a low-frequency of 150 Hz and a high-frequency of 2000 Hz.

We investigated whether certain identifiable thoracic and abdominal hairs enable the caterpillars to hear these specific frequencies through a series of experiments with and without the hairs removed. Please watch the video.

The result of the behavioral response comparisons before and after removal of the hairs on each caterpillar showed a greatly reduced ability of the caterpillars to detect sounds without the hairs. This indicates that M.sexta caterpillars use specific hairs located on their abdomen and thorax for detecting airborne sounds at 150 Hz and 2000 Hz. This provides evidence of non-tympanal sound detection in these caterpillars for these specific frequencies.

Ultrasonic Pest Control To Protect Beehives

New technique uses ultrasonic signals that mimic bat calls to deter wax moths from beehives #ASA_ASJ2025 #ASA189

HONOLULU, Dec. 4, 2025 — Bees, and other pollinator species, are dying. Between pesticides, the climate crisis, and habitat loss, bee colonies are becoming weaker, leaving them more vulnerable to parasites like the greater and lesser wax moths. Vulnerable bees have cascading effects on beekeepers and food security in the apiculture industry.

A team of researchers from the University of Strathclyde and Japan’s National Agriculture and Food Research Organization is exploiting the unusual hearing of wax moths to develop a sustainable and efficient pest control technique that does not harm bees.

Lara Díaz García, postdoctoral researcher at the University of Strathclyde, will present her findings Thursday, Dec. 4, at 10:30 a.m. HST as part of the Sixth Joint Meeting of the Acoustical Society of America and Acoustical Society of Japan, running Dec. 1-5 in Honolulu, Hawaii.

A female specimen of the greater wax moth (Galleria mellonella) in the middle of tethered flight experiments. Credit: Lara Díaz García

A female specimen of the greater wax moth (Galleria mellonella) in the middle of tethered flight experiments. Credit: Lara Díaz García

Wax moths take advantage of weakened bee colonies, tunneling through the hive and feeding on the honeycomb and bee eggs. Removing infestations is labor-intensive — beekeepers must remove individual frames affected by the infestation and catch any remaining wax moths with sticky traps.

These moths can hear sounds four octaves higher than a human can, and this ultrasonic hearing helps them avoid becoming tasty bat food and hear male moth calls. They tell these calls apart based on the timing of the signal and the loudness of the sound.

By analyzing which patterns of bat echolocation calls elicited a stronger neural response in the moths, the researchers determined the best ultrasonic deterrent. Because bees have no sense of hearing, this pest control mechanism does not harm them.

“The technique can be adapted to different moth species; it would require some work for tuning to the most sensitive range to their particular hearing, and then targeting that range, but once that initial part is done, the technique should be applicable to any other moth species capable of hearing — which is the majority of them,” said Díaz García.

The team also developed a simplified model of the lesser wax moth eardrum, capturing its essential features to explain its directional hearing. They hope to generalize their method for other moth species and to develop a commercial pest control device or acoustic sensors inspired by moth ears.

“Nature is truly impressive and inspiring for technological development,” said Díaz García. “It’s also great to contribute to a very tangible outcome of very real problems that we’re seeing due to the climate crisis.”

Contact:
AIP Media
+1 301-209-3090
media@aip.org

——————— MORE MEETING INFORMATION ——————–

Main Meeting Website: https://acousticalsociety.org/honolulu-2025/
Technical Program: https://eppro02.ativ.me/web/planner.php?id=ASAASJ25

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 summaries (300-500 words) 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 and/or 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 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/.

ABOUT THE ACOUSTICAL SOCIETY OF JAPAN
ASJ publishes a monthly journal in Japanese, the Journal of the Acoustical Society of Japan as well as a bimonthly journal in English, Acoustical Science and Technology, which is available online at no cost https://www.jstage.jst.go.jp/browse/ast. These journals include technical papers and review papers. Special issues are occasionally organized and published. The Society also publishes textbooks and reference books to promote acoustics associated with various topics. See https://acoustics.jp/en/.

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