Thursday, October 08, 2026

Healthy reef sounds can boost coral and fish recovery efforts

Two Scripps-led studies show how underwater sound can play a role in restoring degraded coral reefs and rebuilding fish communities

University of California - San Diego

Damselfish swim near artificial reef structure — image:
Damselfish swim near a separately located artificial reef “Stack” structure which were also used in the acoustic enrichment studies.
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Credit: Nina Schiettekatte

Coral reefs are renowned for their visual beauty, but for the marine life they support, their sounds may be just as enticing. Two new studies led by UC San Diego’s Scripps Institution of Oceanography reveal how underwater acoustic enrichment — the playback of sounds from healthy reefs — can help spur the recovery of degraded coral reefs and their fish communities.

These studies — one focusing on coral larvae, and the other focusing on fish larvae — are the first to field test the effects of underwater sound on fish and coral larvae simultaneously, alongside other restoration technologies including living materials and 3D-printed settlement surfaces. The research took place in Hawaii’s Kāne’ohe Bay, located off the island of O‘ahu, over several spawning events in 2023 and 2024.

“We have demonstrated in a single set of field studies that acoustic enrichment works in increasing the presence of both fish larvae and coral larvae on artificial reef structures,” said Scripps Oceanography researcher Aaron Thode, head of the Scripps Environmental Acoustics Lab and lead author of the coral larvae study.

Scripps Oceanography scientists led the studies in collaboration with the University of Hawai’i and other consortium partners of Rapid Resilient Reefs for Coastal Defense (R3D), a project focused on nature-based strategies to reduce wave energy, protect coastlines and improve coral resilience. The studies and broader R3D effort were funded by the Defense Advanced Research Projects Agency (DARPA).

Coral study

The newest study, published Oct. 8 in Communications Biology (part of the Nature Publishing Group), examines how acoustic enrichment affects coral larval settlement — the critical stage when free-drifting larvae search for a place to attach and begin building a reef. The research also demonstrates the potential of living materials and 3-D printed settlement surfaces to enhance coral settlement under natural spawning conditions.

“Our data indicate that when these drifting organisms detect a lot of sound from a reef, it signals to them that this is a good place to settle,” said Thode. “Our analysis also provided strong evidence that synthetic chemical cues attract these organisms to reefs.”

To start, the team collected sounds from a healthy reef environment off O‘ahu, Hawaii. Over the course of a lunar cycle, their recorder captured the sounds of fish and numerous other organisms, including shrimp and crustaceans that produce distinctive snapping noises. (Listen to the sounds of a healthy reef under the new moon, and the distinctive “purr” of a damselfish.)

The researchers then broadcast these recordings from an underwater speaker at the study site — a flat, sandy area off the small island of Moku o Loʻe. For two weeks, the speaker played the reef recordings from sunset to sunrise.

Around the speaker, the team placed 37 artificial structures on the seafloor, at a depth of 4.5 meters (15 feet) and distances between 1 to 42 meters (3 to 138 feet) away. The structures varied in design and surface properties, and included engineered microhabitats developed in Scripps researcher Daniel Wangpraseurt’s Coral Reef Ecophysiology and Engineering Lab.

These microhabitats were engineered in two ways: through their physical architecture, which created complex, protected settlement spaces, and through their living surface coating, made with BRINK — a bioactive “reef ink” containing living bacteria. BRINK was developed by former Scripps postdoctoral researcher Natalie Levy and colleagues in Wangpraseurt’s lab.

Across three experiments conducted over two years, scientific divers measured coral larval settlement one and two weeks after the new moon, when spawning occurs. Using a handheld blue light and yellow filter, they counted the individual larvae that had settled on each structure.

The experiments showed that the structures closest to the speaker had the highest levels of coral settlement. Among those, the structures treated with BRINK had the best results.

“The acoustics help, and with the living biofilm, it's a lot better,” said Thode. “When combined with structures that had crevices, acoustic enrichment worked very well for the coral larvae settlement.”

The study noted that specialized 3D-printed structures developed by colleagues at the Hawaiʻi Institute of Marine Biology also performed well, but those structures were only tested with sound alone and not BRINK. For future experiments, the team recommends combining acoustic enrichment with these more complex structures coated with BRINK for the best chance of coral settlement success.

“We now have evidence that several of these technologies can work in the field, which is a major step forward,” said Wangpraseurt, who is also UC San Diego’s lead principal investigator for the R3D project and a co-author of the study. “It brings us closer to the vision of hybrid reefs, a new class of living coastal infrastructure that combines engineering and biology to protect our shores while supporting the growth and recovery of reef ecosystems.”

Reef fish study

In a related study published recently in Scientific Reports, Scripps PhD candidate Océane Boulais and colleagues used custom-built autonomous cameras to document an increase in fish larvae during the same acoustic enrichment field deployments.

“Fish are important components of healthy coral reefs, because certain species feed on smothering microalgae that would otherwise make it difficult for coral larvae to settle and grow,” said Boulais, the lead author of the study.

Because fish are easily disturbed by humans, monitoring their activity while scuba diving presents a challenge, one Thode likened to “Godzilla trampling through a city and trying to get an accurate count of all the humans scurrying away.” As a solution to this problem, Boulais developed an array of low-power autonomous cameras capable of continuously detecting and counting fish larvae for up to three weeks.

Boulais positioned the cameras near the entrances of complex, 3D-printed structures that functioned as “fish hotels,” documenting fish as they entered and left while also tracking the presence of larvae.

“By developing these non-invasive cameras, we can essentially spy on the fish and observe a lot of their natural behavior,” said Boulais. “The autonomy and long-term monitoring design of these cameras enable us to observe which animals show up, and how long they stay.”

The cameras were deployed at two sites: one near the underwater speaker providing acoustic enrichment, and one at a control site where an identical speaker did not emit any sound.

Larval counts at both sites peaked around the new moon, but the acoustically enriched site attracted 4 to 14 times more fish larvae overall — a promising indication that the added sound helped draw young fish to the structures. The results held even when the team swapped locations of the true speaker and control speaker.

“The cameras are relatively new, but they’re already helping us learn so much about the early life stages of reef fish, and how sound might enhance their presence on a reef,” said Boulais.

Next steps

DARPA plans to install a $22 million hybrid reef structure off Oʻahu this fall, with corals likely to be outplanted in late 2026 or early 2027. The Kalaeloa Hybrid Reef will span 50 meters (164 feet) and incorporate technologies tested through the R3D program, including Scripps-developed microstructures and an acoustic enrichment system.

After installation, DARPA will transition ownership of the prototype living breakwater to the Hawai’i Department of Transportation, a transition partner for the R3D program.

More than 50 researchers and R3D consortium members contributed to the studies as co-authors. View the coral larval study and the fish larvae study online to see the full list of authors.

To learn more about Scripps-led acoustic enrichment research, visit Birch Aquarium’s Living Seas Tropical Pacific exhibit, which features samples of the reef sounds used in these studies.

– Approved for Public Release, Distribution Unlimited.

Journal

Communications Biology

DOI

10.1038/s42003-026-10932-3

Method of Research

Experimental study

Subject of Research

Animals

Article Title

In situ enhancement of coral larval settlement using acoustic enrichment, engineered habitats and living materials

Article Publication Date

8-Oct-2026

Twin study sheds new light on screen time and mental health

Karolinska Institutet

Shared family factors, such as genes and upbringing, are likely to explain a large part of the link between high screen use and mental health problems in young people. This is according to a new study from Karolinska Institutet published in Nature Human Behaviour.

“Our results suggest that the association may in some cases have been overestimated because it has not been possible to fully account for shared family factors,” says Tong Gong, research specialist at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, and the study’s corresponding author alongside Lu Yi, senior researcher at the same department.

The researchers have followed over 21,000 Swedish twins from the age of nine, through their teenage years and into adulthood. The aim was to investigate how leisure-time screen use is linked to symptoms of depression and anxiety over time. By comparing twins within the same family, where one twin used screens more than the other, they were able to study how the association was influenced by shared genetic and environmental factors.

Clear links during adolescence

The clearest associations between screen use and mental health problems were observed during adolescence and for interactive screen activities such as gaming, chatting and surfing the internet. In contrast, significantly weaker or no links were observed for passive activities such as watching TV or videos.

Fifteen-year-olds who spent more than six hours a day on interactive screen activities had more symptoms of depression or anxiety and were more than twice as likely to be diagnosed with such a condition later in life, compared with their peers who spent no more than two hours a day using screens. However, when the researchers compared twins within the same family, most of these links weakened, particularly among identical twins.

“The correlations did not disappear entirely, but they did become significantly weaker, suggesting that both genes and upbringing play an important role,” says Tong Gong.

The researchers emphasise that the results do not mean that screen time is irrelevant to mental health. Interactive screen activities during adolescence were still linked to an increased risk of mental health problems later in life, although the uncertainty increased when shared family factors were included in the analyses.

Examine different types of activities

The study is based on self-reported data on screen use and does not capture exactly what the young people were doing on their screens or why they were using them. Furthermore, the data was collected before social media and smartphones became as integral a part of young people’s everyday lives as they are today.

The next step is to examine different types of screen-based activities in greater detail, studying their content, the motivation behind their use, problematic use and the activities that screen time replaces. In this way, the researchers hope to gain a better understanding of how these complex relationships vary across different age groups and between girls and boys.

“Future recommendations should not focus solely on how much time children and young people spend in front of screens,” says Emma Frans, senior research specialist at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, and co-author of the study. “To be able to give good advice, we also need to understand what they are doing on their screens, why they are doing it, and which individual and family-related factors may affect their well-being.”

The study was conducted by researchers at Karolinska Institutet in collaboration with partners from Sweden, Norway, Denmark, Germany and Australia. It was primarily funded by the Marianne and Marcus Wallenberg Foundation and the Swedish Brain Foundation. One of the co-authors, Henrik Larsson, has received research grants, honoraria, and consultancy fees from pharmaceutical companies outside the scope of this study. The other researchers declare no conflicts of interest.

Publication: “Recreational Screen Use and Internalising Problems from Preadolescence to Young Adulthood in a Longitudinal Twin Cohort with Co-Twin Comparison”, Tong Gong, Emma Frans, Anna Ohlis, Shuyang Yao, Ruyue Zhang, Anders Nilsson, Yasmina Molero, Miriam A Mosing, Isabell Brikell, Henrik Larsson, Paul Lichtenstein, Lisa B Thorell, Patrik KE Magnusson, Ralf Kuja-Halkola, Yi Lu, Nature Human Behaviour, online 8 October 2026, doi: 10.1038/s41562-026-02607-0.

Journal

Nature Human Behaviour

DOI

10.1038/s41562-026-02607-0

Method of Research

Observational study

Subject of Research

People

Article Title

Recreational Screen Use and Internalising Problems from Preadolescence to Young Adulthood in a Longitudinal Twin Cohort with Co-Twin Comparison

Article Publication Date

8-Oct-2026

Blue light could cut food poisoning from raw chicken

The low-cost technique is also a viable alternative to chlorination

University of Reading

A low-power blue light could be the key to significantly reducing food poisoning caused by raw chicken in the UK, scientists at the University of Reading have found.

Campylobacter is the most common cause of bacterial food poisoning worldwide. In the UK alone there are hundreds of thousands of cases each year, costing an estimated £700 million annually in healthcare and lost productivity.

In a study published today [6 October] in the journal Microbiology, researchers from Reading, working in collaboration with the Animal and Plant Health Agency, tested a new technique known as violet-blue photodynamic inactivation (VB-PDI) against 64 different strains of Campylobacter, which is found in around three quarters of all raw chicken sold in the UK. Every single strain was killed by the treatment, regardless of species or antibiotic resistance profile.

The findings build on previous research that showed blue light treatments could work more effectively than treating chicken with chlorine to kill off specific strains of bacteria. Chlorinated chicken is common in the US, but is not commonly found in Europe, and is a high-profile example of differing food standards and trade barriers between US and Europe.

While cooking kills Campylobacter, cross-contamination from handling raw meat is thought to be the main route of infection. Symptoms typically last about a week and include stomach cramps, fever, nausea and, in many cases, bloody diarrhoea.

VB-PDI works by shining a safe, visible violet-blue light onto bacteria, causing molecules naturally found inside their cells to produce lethal levels of destructive compounds called reactive oxygen species. Crucially, the method needs no physical contact with the food and no added chemicals, making it a promising option for use on poultry carcasses in processing plants after slaughter, before products reach consumers.

The researchers estimate that if the technique could reduce contamination on chicken carcasses by a factor of 100, the proportion of highly contaminated carcasses reaching retail could fall from around 1 in 10 to just 1 in 50.

The team also found no evidence that Campylobacter bacteria could develop resistance to the treatment. Strains that were already resistant to antibiotics were killed just as effectively as fully susceptible ones. When one strain was repeatedly exposed to the light over 15 rounds in the laboratory, in an attempt to force resistance to evolve, no increase in tolerance was seen.

Dr Aidan Taylor, from the University of Reading and lead author of the study, said: "Campylobacter is a genuinely nasty bug, and its sheer abundance in the food chain, combined with rising antibiotic resistance, makes it a really difficult problem to tackle.

“What's exciting about this light-based approach is that it doesn't rely on chemicals or antibiotics at all, so it sidesteps the resistance problem entirely. We've shown it works against a wide range of real-world strains taken directly from UK poultry, including the multi-drug resistant strains that worry us most, and we can't find any evidence that resistance could evolve. That combination of broad efficacy and durability is what makes this such a promising option for cutting contamination before chicken ever reaches someone's kitchen."

Because VB-PDI uses simple, low-power LEDs with a long lifespan and minimal running costs, the team also believe it could offer a low-cost option for poultry producers, including in low- and middle-income countries where food safety infrastructure is limited.

The Animal and Plant Health Agency surveillance programme provides a uniquely detailed picture of the Campylobacter strains circulating in UK poultry. This allowed scientists to test the technology against a real diversity of bacteria, rather than laboratory strains alone.

Dr Samuel Connelly, from the Animal and Plant Health Agency, who co-led the research, said: “The consistent results observed across multiple species and resistance profiles are highly encouraging. While further evaluation using contaminated meat samples is required, the simplicity and adaptability of this technology suggest that it could be implemented at various stages of the food production process. Such application has the potential to reduce the prevalence of Campylobacter within the food chain and, consequently, contribute to a reduction in the incidence of foodborne illness.”

Earlier work by the same team uncovered the molecular reasons why Campylobacter is so sensitive to violet-blue light. The researchers say further trials on naturally contaminated poultry carcasses in real processing settings are now needed before the technology could be rolled out commercially.

Journal

Microbiology

DOI

10.1099/mic.0.001769

Method of Research

Experimental study

Subject of Research

Cells

Article Title

One light to rule them all: photodynamic inactivation of diverse Campylobacter

Article Publication Date

6-Oct-2026

Turning invasive plants into powerful filters for fluoride-contaminated water

Nano-magnesium oxide combined with plant-derived pyro-hydrochar achieves high fluoride adsorption while offering a new route for invasive biomass utilization

Shenyang Agricultural University Collaborative Journals

image:
Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms
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Credit: Yao Tong, Donglin Wang, Lingqing Gu, Yujie Tai, Xianjie Tang, Xi Zhang, Rongdi An, Til Feike & Jiunian Guan

Excess fluoride in water is a persistent environmental and public health concern in many parts of the world. Now, researchers have developed a new plant-derived material that can capture fluoride efficiently while also creating value from invasive plant biomass.

A research team led by Jiunian Guan at Northeast Normal University has developed a nano-magnesium oxide modified pyro-hydrochar, or nMgO/Py-HyC, made from residues of the invasive plant Rhus typhina. The material achieved a maximum fluoride adsorption capacity of 469.64 milligrams per gram, outperforming the MgO-based adsorbents compared in the study.

“Our goal was to address two environmental challenges at the same time: fluoride contamination in water and the growing accumulation of invasive plant biomass,” said Jiunian Guan, corresponding author of the study. “By converting this biomass into a functional carbon material and combining it with nano-magnesium oxide, we created an adsorbent with strong fluoride-removal performance and promising environmental adaptability.”

Fluoride occurs naturally in groundwater, but industrial activities such as semiconductor manufacturing, glass production, electroplating, lithium refining, pesticide production and pharmaceutical manufacturing can also generate fluoride-containing wastewater. Excessive fluoride exposure can cause serious health problems, making effective treatment technologies important for both drinking water protection and industrial wastewater management.

The researchers first converted Rhus typhina biomass into hydrochar and then produced the magnesium-containing composite through a relatively simple pyrolysis process. The resulting porous carbon structure helped disperse nano-MgO particles and provided numerous sites where fluoride could be captured.

A major advantage was the material's ability to perform under different water conditions. Fluoride adsorption remained stable across a broad pH range from 5.0 to 11.0. Common coexisting ions such as nitrate and sulfate caused little interference, although high concentrations of bicarbonate reduced fluoride uptake.

Detailed material analyses revealed that fluoride was not captured through a single process. Instead, several mechanisms worked together, including electrostatic attraction, surface complexation, anion and ligand exchange, precipitation, and hydrogen bonding. Fluoride could interact directly with magnesium and form stable compounds such as MgF₂ and fluorine-containing magnesium hydroxide phases.

The researchers also observed a clear synergistic effect between the carbon support and nano-MgO. Under the same experimental conditions, the adsorption capacity of the combined material was substantially greater than the capacities of the two components considered separately. Its porous framework helped expose active magnesium sites and improved contact between fluoride ions and the adsorbent.

The study therefore points to a potential circular strategy: invasive plant residues can be transformed from an ecological management burden into a useful material for water remediation.

The authors note that further work is needed to evaluate the material under different real-world wastewater conditions and at engineering scale. Still, the findings provide a promising foundation for developing high-efficiency, low-carbon fluoride treatment technologies based on renewable biomass resources.

===

Journal reference: Tong Y, Wang D, Gu L, Tai Y, Tang X, et al. 2026. Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms. Biochar X 2: e023 doi: 10.48130/bchax-0026-0021

https://www.maxapress.com/article/doi/10.48130/bchax-0026-0021

===

About the Journal:

Biochar X (e-ISSN: 3070-1686) is an open access, online-only journal aims to transcend traditional disciplinary boundaries by providing a multidisciplinary platform for the exchange of cutting-edge research in both fundamental and applied aspects of biochar. The journal is dedicated to supporting the global biochar research community by offering an innovative, efficient, and professional outlet for sharing new findings and perspectives. Its core focus lies in the discovery of novel insights and the development of emerging applications in the rapidly growing field of biochar science.

Journal

Biochar X

DOI

10.48130/bchax-0026-0021

Method of Research

Experimental study

Article Title

Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms

Even brief e-cigarette use can cause lasting lung damage and weaken defenses against respiratory viruses, study finds

National Jewish Health

Just days of e-cigarette vapor exposure can injure the lungs' most delicate tissue and leave it more vulnerable to viral infection, according to a study led by National Jewish Health researchers and published in JCI Insight.(Opens in a new window)

The research team studied human lung epithelial and endothelial cells, along with precision-cut human lung tissue, all taken from the distal lung — the deep, delicate region where oxygen passes into the bloodstream. They exposed these tissues to e-cigarette vapor alone, and separately tested vapor exposure followed by infection with a respiratory virus, in preclinical models. Within 24 hours, e-cigarette vapor damaged the protective barrier of the distal lung, triggered cellular stress, impaired cells’ internal process for clearing damaged components, slowed cell growth and repair, and increased cell death.

Strikingly, signs of lung stress persisted 10 days after just a five-day exposure period ended. The team observed lasting changes in barrier function, tissue remodeling, and Th1 immunity — a branch of the immune system critical to fighting viral infections.

Prior vaping exposure also increased SARS-CoV-2 viral burden and suppressed several antiviral genes following infection.

“Our findings suggest that even short-term vaping exposure can initiate injury in the deepest and most delicate regions of the lung,” said senior author Irina Petrache, MD, pulmonologist and chief of the Division of Pulmonary, Critical Care and Sleep Medicine at National Jewish Health. “Importantly, some effects persisted after exposure ended and altered the immune response to a subsequent viral infection.”

The findings, which will need to be confirmed in future studies in people, point to biological mechanisms that may help explain why vaping has been linked to lung injury and greater susceptibility to respiratory infections. The researchers noted that repeated exposure could potentially contribute to chronic lung disease by sustaining cellular injury and disrupting normal repair.

National Jewish Health is the leading respiratory hospital in the nation delivering excellence in multispecialty care and world class research. Founded in 1899 as a nonprofit hospital, National Jewish Health today is the only facility in the world dedicated exclusively to groundbreaking medical research and treatment of children and adults with respiratory, cardiac, immune and related disorders. Patients and families come to National Jewish Health from around the world to receive cutting-edge, comprehensive, coordinated care. To learn more, visit njhealth.org or the media resources page.

Journal

JCI Insight

DOI

10.1172/jci.insight.198757

Article Title

E-cigarette exposure triggers distal lung cell injury, persistent lung stress response, and antiviral immune suppression