Brandyn Lucca – blucca@uw.edu
Bluesky: @brandynlucca.bsky.social
Instagram: @brandynmark
Applied Physics Laboratory, University of Washington, Henderson Hall (HND), 1013 NE 40th St, Seattle, Washington, 98105, United States
Joseph Warren
Instagram: @warren.bioacoustics.lab
Bluesky: @warren-lab.bsky.social
Affiliation: School of Marine and Atmospheric Sciences, Stony Brook University
Popular version of 2aAO9 – Active acoustic detection of fish and zooplankton along bathymetric features of the New York Bight
Presented at the 188th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0037522
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Imagine standing on the beach in New York City, looking beyond the harbor over the horizon where rolling waves meet an armada of ships lined up to unload their cargo. What remains hidden from view are the vast underwater plains, valleys, and canyons teeming with marine life beneath the surface. From a bird’s-eye view, this area forms the New York Bight, a stretch of ocean off the coast of New York City situated between southern New Jersey and eastern Long Island. This seascape offers prime real estate for animals ranging from copepods to whales.
Some animals often gather along the shelfbreak, where the relatively flat, shallow seafloor of the continental shelf dramatically changes to the deep sea. Others prefer life in a well-known ecological hotspot and one of the largest marine canyons in the world: the Hudson Canyon. Like many people, marine animals choose habitats based on the amenities they offer, but their preferences can evolve as they age or in response to environmental shifts. Some may leave the New York Bight entirely, while others may settle in undiscovered hotspots elsewhere. But how can scientists find these hotspots in the first place?
How do scientists “see” beneath the waves?
Researchers use a technique called “active acoustics” to get snapshots of where animals are in the water column across large areas that can complement other sampling methods like nets. With this approach, they send out short pulses of sound from a moving ship and measure the echoes that bounce back from the seafloor or are created from animals that live in the water column. The equipment scientists use to measure these echoes is similar to bottom-finders and fish-finding systems used by fishers and boaters. The results can reveal dense fish schools clustered along the steep walls of a canyon or zooplankton aggregations in the near-surface waters along the shelfbreak. These patterns help scientists better understand how seascapes shape habitat preferences among marine organisms (Figure 1).
Echograms are one way to visualize acoustic backscatter, with color scale units corresponding to the total energy in echoes measured from marine organisms. This echogram reveals how animals are distributed vertically in the water column along a ship transect that crossed the Hudson Canyon. The dark gray region corresponds to the seafloor.
To carry out this research, scientists measure echoes from animals in the water column, collect fish and zooplankton using nets and trawls, and measure how temperature and salinity (and other environmental factors like oxygen) vary in the ocean as you go down in depth. Researchers collected the data for this study during seasonal surveys aboard a research vessel that covered the waters south of Long Island, New York, out to the shelfbreak, approximately 140 miles away (Figure 2).
Acoustic surveys were conducted along seven transect lines (black lines) with biological and seawater sampling stations at each square point. The white lines represent isobaths, or lines of constant depth, at 25, 50, 100, 500, 100, and 2000 m. The orange and red stars indicate where the Hudson Shelf Valley and Hudson Canyon begin.
Location, location, location: Hotspots change with the seasons
The New York Bight regions with the most fish and zooplankton (as measured by our echosounders) change with the seasons. In winter and early spring, most organisms concentrated farther offshore, often along the canyon edges or beyond the shelfbreak. As summer arrives, these biological hotspots grow along the shelfbreak, especially in and around the canyons, and move closer to shore. By fall, acoustic measurements showed that fish and zooplankton spread more evenly across the continental shelf.
For fish living near the seafloor, a seasonal feature called the Mid-Atlantic Cold Pool plays a major role in their movements. This layer of cold water forms on and above the seafloor over part of the continental shelf each spring and slowly decreases in volume throughout the summer. When the Cold Pool forms, many near-bottom fish shift away from their spatial extent due to the fish having temperature preferences and gather in the Hudson Canyon, other shelfbreak canyons, inshore areas, and the Hudson Shelf Valley. As the Cold Pool shrinks in late summer, their distribution becomes more like the broader patterns observed for overall biological backscatter (Figure 3).
An example echogram of biological backscatter near the shelfbreak. The 9º (gray) and 10º (black) isotherms, or lines of constant temperature, approximate the lateral and vertical extent of the Mid-Atlantic Cold Pool that, in this case, nearly walled this aggregation off from the inshore waters on the continental shelf entirely.
From underwater sound to action: Guiding management decisions
The New York Bight is a dynamic and productive ecosystem that experiences significant fishing pressure, shipping activity, and offshore energy development. By combining acoustic surveys with biological net sampling and oceanographic measurements, scientists can identify areas that fish and zooplankton may prefer (or avoid) throughout the year. Surveys such as this one help guide management decisions that balance the economic and commercial health of the New York Bight.
Brijonnay Madrigal – bcm2@hawaii.edu Instagram: @brijonnay Marine Mammal Research Program University of Hawaiʻi at Mānoa 46-007 Lilipuna Rd Kaneohe, HI 96744 United States
Marine Mammal Research Program @mmrp_uh
Popular version of 5aAB – Acoustic behavior of endangered false killer whales (Pseudorca crassidens) using biologging devices in Hawaiʻi Presented at the 188th ASA Meeting Read the abstract at https://doi.org/10.1121/10.0038276
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
How do scientists better understand the communication of individual animals when we don’t know who is speaking and what they are doing underwater? For cetaceans (whales/dolphins/porpoises), passive acoustic monitoring is an important approach to study these animals that spend most of their time underwater and rely on acoustic signaling to communicate. The use of acoustic biologging tags has enabled the collection of high-resolution data to study acoustic behavior of top predators. The Main Hawaiian Islands (MHI) insular population of false killer whales (Pseudorca crassidens) is the most endangered toothed whale population in Hawaiʻi under the Endangered Species Act. Despite ongoing management efforts to address threats, the population has continued to decline to a current population size of less than 150 individuals. Therefore, it is crucial to understand the behavior of this population to better inform conservation measures critical for the protection of this species. Our understanding of the social context of individual false killer whales has generally been limited, until now.
The goal of this study was to use data recorded from non-invasive archival , suction-cup tags, to describe the acoustic behavior of MHI insular false killer whales to better understand the behavioral context of social signals. Our objectives were to (1) classify and characterize the repertoire of individual false killer whales; (2) describe nonlinear features observed in calls that enhance communication between individuals; and (3) analyze the relationship between social sound production and diving behavior. These findings can help us evaluate social context on a small scale and provide foundational information to determine the potential function of these signals.
Our results show that MHI insular false killer whales have a more diverse repertoire than previously described. Some call types are shared between individuals, and some are unique to individuals. We identified predominate call types that are repeated or favored by specific individuals and call rates vary by individual across dive states (for example – descent, ascent) (Figure 1). Most calls are biphonic, where the animals produce a call and clicks simultaneously (Audio 1). Although clicks are commonly used for echolocation to navigate and locate prey, the clicks produced by these animals occur with calls at the same time in distinct patterns, so they likely function in communication and encode additional information for individuals. This study provides invaluable insights into this species’ social behavior and by intercepting the coconut wireless of Hawaiʻi false killer whales using tag technology, our findings can inform management strategies necessary to advance conservation efforts of this top predator to the Hawaiʻi ecosystem.
Figure 1: A spectrogram of three predominate call types produced by one tagged false killer whale from the Main Hawaiian Islands insular population. Calls are biphonic which means a call and clicks are produced simultaneously, as indicated by the arrows in the first panel. A spectrogram is a visual representation of sound with time on the x-axis, frequency (or pitch) on the y-axis, and color representing the relative amplitude (loudness) of the sound.
MELVILLE, N.Y., Nov. 21, 2024 – In the winter of 2022-2023, nearly a dozen whales died off the coast of New Jersey, near the sites of several proposed wind farms. Their deaths prompted concern that related survey work being conducted in the area somehow contributed to their deaths.
Michael Stocker of Ocean Conservation Research will present his work Thursday, Nov. 21, at 3:29 p.m. ET in a session dedicated to examining the circumstances surrounding these whale deaths, as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.
Researchers retrieve an instrument package from the Cook Inlet. Could noise from these surveys like these have led to the death of almost a dozen whales during winter of 2022-2023? Credit: Michael Stocker
In pursuit of clean energy goals and to reduce atmospheric carbon emissions, developers are increasingly exploring building wind turbines in the waters off the East Coast of the United States. Three offshore wind farms are already in operation, with several more planned or underway. These wind farms stand to generate a significant amount of carbon-free electricity, which can help coastal states meet their decarbonization goals.
The increased presence of these turbines in coastal waters, along with the noise from construction and surveys, has led to concerns of their impact on marine life. In particular, cetaceans such as whales and dolphins are likely to be sensitive to the noises and increased marine traffic brought by these turbines.
However, the Marine Mammal Commission, a federal oversight agency, states there is no evidence linking the whales that died in the New Jersey region in the winter of 2022-2023 to wind energy development.
According to necropsies performed on recovered whales, many of them died from collisions with ships. The Marine Mammal Commission notes that this is not a particularly unusual occurrence, nor is the number of whale deaths in this period higher than average. A rise in ship strikes over the last decade is mostly due to a simple combination of more whales plus more ships.
“In the case of a lot of whales, population recoveries since the cessation of commercial whaling are coincident with increasing shipping traffic and increasing fishing efforts,” said Stocker. “This is resulting in increased interactions between whales and the industrialization of the ocean.”
Stocker, however, is concerned that the increased presence of survey ships in and around New Jersey waters may have exacerbated this issue.
“Were the ship strikes just a coincidence?” asked Stocker. “Or were they a product of compromised whale vigilance due to aggregated stress factors?”
Survey ships are employed by wind farm developers to map the seafloor in preparation for construction. These ships use underwater acoustic devices in their efforts, which can stress marine mammals such as whales. While one survey ship likely has little effect, Stocker highlights that 11 different surveys were operating in the region from December 2022 to March 2023, and that the cumulative impact of these surveys has not been properly evaluated.
Stocker hopes his Thursday session will spark a discussion among attendees with the goal of identifying approaches to minimize whale deaths in the future.
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 virtual 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/.
MELVILLE, N.Y., Nov. 21, 2024 – Mysterious, repeating sounds from the depths of the ocean can be terrifying to some, but in the 1980s, they presented a unique look at an underwater soundscape.
In July 1982, researchers in New Zealand recorded unidentifiable sounds as a part of an experiment to characterize the soundscape of the South Fiji Basin. The sound consisted of four short bursts resembling a quack, which inspired the name of the sound “Bio-Duck.”
Looking from the stern of the ship as it tows the long horizontal array of hydrophones. The tow cable can be seen going through the metal horn at the stern. The hydrophone array is several hundred meters behind the ship and about 200 meters deep. Credit: Ross Chapman
“The sound was so repeatable, we couldn’t believe at first that it was biological,” said researcher Ross Chapman from the University of Victoria. “But in talking to other colleagues in Australia about the data, we discovered that a similar sound was heard quite often in other regions around New Zealand and Australia.”
They came to a consensus that the sounds had to be biological.
Chapman will present his work analyzing the mystery sounds Thursday, Nov. 21, at 10:05 a.m. ET as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.
“I became involved in the analysis of the data from the experiment in 1986,” Chapman said. “We discovered that the data contained a gold mine of new information about many kinds of sound in the ocean, including sounds from marine mammals.”
“You have to understand that this type of study of ocean noise was in its infancy in those days. As it turned out, we learned something new about sound in the ocean every day as we looked further into the data—it was really an exciting time for us,” he said.
However, the sounds have never been conclusively identified. There are theories the sounds were made by Antarctic Minke whales, since the sounds were also recorded in Antarctic waters in later years, but there was no independent evidence from visual sightings of the whales making the sounds in the New Zealand data.
No matter the animal, Chapman believes that the sounds could be a conversation. The data was recorded by an acoustic antenna, an array of hydrophones that was towed behind a ship. The uniqueness of the antenna allowed the researchers to identify the direction the sounds were coming from.
“We discovered that there were usually several different speakers at different places in the ocean, and all of them making these sounds,” Chapman said. “The most amazing thing was that when one speaker was talking, the others were quiet, as though they were listening. Then the first speaker would stop talking and listen to responses from others.”
He will present the waveform and spectrum of the recordings during his session, as well as further evidence that the work was a conversation between multiple animals.
“It’s always been an unanswered issue in my mind,” Chapman said. “Maybe they were talking about dinner, maybe it was parents talking to children, or maybe they were simply commenting on that crazy ship that kept going back and forth towing that long string behind it.”
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 virtual 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/.
Saeed Shafiei Sabet – s.shafiei.sabet@guilan.ac.ir
Twitter: @SaeedSHSABET
Instagram: @s.shafiei.sabet.anim.beh
Fisheries Department, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Guilan, 1144, Iran
Popular version of 3aAB2 – Experimental sound exposure studies on aquatic animals; an early attempt to develop underwater bioacoustics in Iran
Presented at the 187th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0035189
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Impact of sound on aquatic animals
Human-generated sound, called ‘anthropogenic sound,’ is now widely recognized as an environmental stressor. It affects aquatic life in both marine and freshwater habitats. Over the last few decades, policy makers, animal welfare communities, behavioural biologists and environmental managers have been increasingly interested in understanding how man-made sound may lead to negative consequences on both terrestrial and underwater animals. Aquatic animals can be negatively affected by anthropogenic sound in many ways. For example anthropogenic sound can mask biologically relevant sounds, cause attentional shifts, affect foraging performance and interfere in communications in aquatic animals among taxa. Therefore, we need to understand how anthropogenic sound may affect individuals, to eventually be able to assess the impact of anthropogenic sound on populations, communities, and ecosystems.
Many crustaceans and fish species have been artificially introduced to confined areas for different purposes. Crustaceans and fish are being used in laboratory conditions for scientific research, in aquaria and zoos for entertainment, as well as in aquaculture facilities (e.g., cages, races, pens) for breeding, restocking and harvesting around the world. As a result, aquatic animals in captivity may be continuously exposed to a variety of sound sources. Although there are relatively well-documented studies exploring anthropogenic sound effects on aquatic animals across taxa in the Global North Countries, this field of research is less developed in the Global South Countries. Moreover, policy makers have already set regulations for marine environments to safeguard a so-called good environmental status, but there are no agreements yet for freshwater habitats. This means freshwater crustaceans and fishes in a diversity of waterbody types are more or less exposed to man-made sound without any incentive to control impact and without any protection by law.
Sound exposure studies
To better understand how sound affects aquatic animals, I conducted several sound exposure studies on captive fish and crustaceans. In my experimental studies, I explored how anthropogenic sound affects captive fish (e.g., zebrafish and guppy) and crustaceans (red cherry shrimp). Figure 1 illustrates behavioral changes in red cherry shrimp when exposed to different sound levels, showing how they react to sound stress.
I examined various sound exposure treatments to provide insights that may be useful for future explorations for indoor and outdoor sound impact studies as well as for assessing animal welfare and productivity in captive situations. For example, I explored short-term behavioural parameters, which are indicators of sound-related stress, disturbance and deterrence. My findings may also raise awareness for sound levels in laboratories and the potential effect on reliability for fish as a model species for medical and pharmaceutical studies. As a follow-up step of my PhD research, I also explored the complexity of sound fields in indoor fish tanks by selecting a different set-up for each study, which makes behavioural analyses and direct comparisons not only relevant within each study, but also provides insight into the role of fish tank acoustics on ‘natural’ and experimental exposure conditions. Several behavioural states are likely to reflect considerable changes in underlying physiology, which would be interesting and feasible to investigate for more long-term consequences, but this was beyond the scope of the current step of my research lab priorities.
Development of bioacoustics in Iran and future directions
This research study is a pioneering effort in a relatively new field in Iran. This research is important because Iran has a broad range of coastlines with The Caspian Sea, The Persian Gulf and Oman Sea and there are quite diverse habitats and fragile ecosystems in these aquatic areas (See figure 2). However, yet there are large gaps in our knowledge of effects of anthropogenic sound on aquatic animals in Iran. Further studies are needed to assess anthropogenic sound impacts on aquatic animals and the potential cascading effects at the community level of the aquatic environment in Iran. This research, a series of experiments, lays the groundwork for future bioacoustics studies in Iran and other countries in the West Asia. I call, therefore, for more grounded laboratory-based and field based empirical research of global collaborations and high quality data collection towards open science in bioacoustics.
Figure 2. An overview of the geographical location of Iran’s aquatic habitats (yellow circles); The Caspian Sea in the north of Iran and The Persian Gulf and The Gulf of Oman/Oman Sea. Image courtesy of: https://www.google.com/maps
Acknowledgments
Finally, I am very grateful to my graduate M.Sc. students: Reza Mohsenpour, Sasan Azarm-Karnagh, Marziyeh Amini Fard for their excellent collaborations in behavioural studies and high quality data collection at the Fisheries Department, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. I established and set up my research lab in 2016 and actively recruit enthusiastic undergraduate and graduate students by organizing workshops, seminars, mini research projects and relevant course material to develop this field of academic research in Iran. Hereby I would like to thank Hans Slabbekoorn my PhD supervisor at Leiden University who have helped and supported me to develop my underwater bioacoustics lab in my home country, Iran.
Selected references:
Azarm-Karnagh, S., López Greco, L., & Shafiei Sabet, S. (2024). Anthropogenic noise impacts on invertebrates: case of freshwater red cherry shrimp (Neocaridina davidi). In The Effects of Noise on Aquatic Life: Principles and Practical Considerations (pp. 1-12). Cham: Springer International Publishing.
Azarm-Karnagh, S., López Greco, L., & Shafiei Sabet, S. (2023). Annoying noise: effect of anthropogenic underwater noise on the movement and feeding performance in the red cherry shrimp, Neocaridina davidi. Frontiers in Ecology and Evolution, 11, 1091314.
Shafiei Sabet, S., Karnagh, S. A., & Azbari, F. Z. (2019). Experimental test of sound and light exposure on water flea swimming behaviour. In Proceedings of Meetings on Acoustics (Vol. 37, No. 1). AIP Publishing.
Radford, A. N., Kerridge, E., & Simpson, S. D. (2014). Acoustic communication in a noisy world: can fish compete with anthropogenic noise?. Behavioral Ecology, 25(5), 1022-1030.
Slabbekoorn, H., Bouton, N., van Opzeeland, I., Coers, A., ten Cate, C., & Popper, A. N. (2010). A noisy spring: the impact of globally rising underwater sound levels on fish. Trends in ecology & evolution, 25(7), 419-427.
Popper, A. N., & Hastings, M. C. (2009). The effects of anthropogenic sources of sound on fishes. Journal of fish biology, 75(3), 455-489.
Figure 1. Behavioral changes of the freshwater red cherry shrimp in response to an underwater speaker. Behavioral responsiveness of shrimp when exposed to acoustic stimuli was categorized as movement activity impacts and feeding activity impacts (Image courtesy of: Azarm-Karnagh et al., 2023; © 2024 Springer Nature).
Figure 2. An overview of the geographical location of Iran’s aquatic habitats (yellow circles); The Caspian Sea in the north of Iran and The Persian Gulf and The Gulf of Oman/Oman Sea. Image courtesy of: