Acaulis rosae

In a new study led by <a href="https://www.curtin.edu.au/">Curtin University</a>, experts report that <a href="https://www.earth.com/news/fireworks-release-toxic-metals-that-can-harm-human-cells/">fireworks</a> should be replaced with cleaner drone and laser light shows to prevent "highly damaging” impacts. Lead author Professor Bill Bateman noted that fireworks remain globally popular despite the overwhelming evidence that they negatively impact wildlife, domestic animals, and the environment.



“Fireworks create short-term noise and light disturbances that cause distress in domestic animals that may be managed before or after a firework event, but the impacts to wildlife can be on a much larger scale,” said Professor Bateman.



“The annual timing of some large-scale firework events coincides with the migratory or reproductive movements of wildlife, and may therefore have adverse long-term population effects on them. Fireworks also produce significant pulses of highly pollutant materials that also contribute significantly to the chemical pollution of soil, water, and air, which has implications for human as well as animal health.”



To investigate the potential harm caused by firework displays, the researchers reviewed the ecological effects of Diwali festivities in India, Fourth of July celebrations across the United States, and other events in New Zealand and Europe.&nbsp;



The review confirmed that fireworks affect wildlife in the long-term. For example, the experts found that sea lions along the coastline of Chile have changed their breeding season as a result of New Year’s fireworks. In California, July firework displays are associated with a decline of Brandt’s cormorant colonies. Furthermore, Spanish festivals have been linked to lower breeding success among house sparrows.



Professor Bateman said that firework bans at sensitive periods for wildlife migration or mating periods could limit these ecological impacts.



“Other than horses, for which there is some evidence that they can be gradually familiarized with flashes of light, there is very little that can be done to address the disturbing impact of noise from fireworks on animals and wildlife,” said Professor Bateman.



“The future of firework displays may be in the use of safer and greener alternatives such as drones, eco-friendly fireworks or visible-wavelength lasers for light shows."



“There is growing evidence that these community events can be managed in a sustainable way and it’s clear that out-dated firework displays need to be replaced by cleaner options that are not harmful to wildlife and the environment.”



The study authors noted that firework residues also contribute significantly to chemical pollution of soil, water, and air, which has implication for human as well as animal health. 



"Modern technological alternatives to traditional fireworks - both ‘eco-friendly’ fireworks, and reusable drone and laser-based light shows - provide safer, ‘greener’ alternatives that also present a sustainable way forward for maintaining cultural traditions without perpetuating their adverse impacts," wrote the researchers.



The study is published in the journal <a href="http://dx.doi.org/10.1071/PC22040">Pacific Conservation Biology</a>.



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



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Fireworks can have long lasting impacts on wildlife

In a new study led by Curtin University, experts report...

Honey bees are crucial <a href="https://www.earth.com/news/gardeners-can-make-small-changes-to-benefit-pollinators/">pollinators</a> of flowers, enabling the plants to form seeds and fruit, and reproduce successfully. In addition, around one-third of food eaten in by Americans comes from crop plants that are pollinated by honey bees. The collapse of bee colonies thus poses a threat to food security and is a phenomenon that concerns beekeepers across the U.S. and worldwide.



The sudden disappearance of all the worker bees from a colony, leaving a queen, a few nurse bees and the immature brood, is what characterizes colony collapse. The colony cannot survive without the worker bees, and so it will die off in time. There is currently no all-embracing explanation for why this occurs to certain bee hives and the research that has been conducted usually focuses on the effects of one stressor, such as parasites, or on a combination of stressors in one isolated region or geographical area.&nbsp;



A new study, published in the journal <a href="http://dx.doi.org/10.1038/s41598-023-28374-w">Scientific Reports</a>, has taken the analysis of variables, recognized as potential contributors to colony collapse, to a higher level. The researchers conducted a large-scale, multi-variable analysis using publicly accessible datasets from across the contiguous U.S. In particular, they used weather data for the years 2015–2021, and combined open data on honey bee colony status and stressors, weather data, and land use, in order to understand the relationships between the disappearance of bee colonies and the various stressors.



“Honey bees are vital pollinators for more than 100 species of crops in the United States, and the widespread loss of honey bee colonies is increasingly concerning,” said Luca Insolia, first author of the study, a visiting graduate student in the Department of Statistics at <a href="https://www.psu.edu/">Penn State</a> at the time of the research, and currently a postdoctoral researcher at the University of Geneva in Switzerland.&nbsp;



“Some previous studies have explored several potential stressors related to colony loss in a detailed way but are limited to narrow, regional areas. The one study that we know of at the national level in the United States explored only a single potential stressor. For this study, we integrated many large datasets at different spatial and temporal resolutions and used new, sophisticated statistical methods to assess several potential stressors associated with colony collapse across the U.S.”



One of the main reasons for the lack of previous analyses at the national level is the absence of same-source or same-resolution databases. For example, weather data may be available on a daily scale, but information on colony disappearances may only be collected by apiculture groups on a quarterly basis. Because these data differ in spatio-temporal resolution, the researchers used a method of data up-scaling, rather than averaging the information to the lowest resolution available, which would mean a loss of detail.



“In order to analyze the data all together, we had to come up with a technique to match the resolution of the various data sources,” said Martina Calovi, corresponding author of the study, a postdoctoral researcher in the Department of Ecosystem Science and Management at Penn State at the time of the research, and currently an associate professor of geography at the Norwegian University of Science and Technology.&nbsp;



“We could have just taken an average of all the weather measurements we had within a state, but that boils all the information we have into one number and loses a lot of information, especially about any extreme values. In addition to averaging weather data, we used an ‘upscaling’ technique to summarize the data in several different ways, which allowed us to retain more information, including about the frequency of extreme temperature and precipitation events.”



The researchers used the resulting integrated resolution-matched dataset – which they have made available for use by other researchers – alongside sophisticated statistical modeling techniques that they developed to assess the large number of potential stressors at the same time.



The research team found that several stressors impacted honey bee colony loss at the national level, including the use of pesticides nearby, frequent extreme weather events, and weather instability. Colony loss was also related to the presence of parasitic mites, Varroa destructor, which reproduce in honey bee colonies, weaken the bees, and potentially expose them to viruses. The researchers also found that losses typically occurred between January and March, probably reflecting the harsher conditions endured by bees while overwintering.&nbsp;



“Our results largely reinforce what regional studies have observed and confirm that regional patterns around these stressors are actually more widespread,” said Insolia, a beekeeper himself. “These results also inform actions that beekeepers could take to help circumvent these stressors and protect their colonies, including treatments for the Varroa mites‚ especially in areas of weather instability. Beekeepers could also consider strategies to move their colonies to areas with high food availability or away from nearby pesticides or to provide supplementary food during certain seasons or months with frequent extreme weather events.”



The researchers suggest that having data about beekeeping practices, such as treating colonies for Varroa mites and recording colony losses, at a finer resolution would allow validation of their results as well as a more detailed understanding of factors that act as stressors for honey bees.&nbsp;



“It would be incredibly beneficial to explore beekeeping practices at a finer scale than the state level,” said Calovi. “In many cases, beekeeping associations and other organizations collect this data, but it is not made available to researchers. We hope our study will help motivate more detailed data collection as well as efforts to share that data – including from smaller organizations such as regional beekeeper associations.”



The research team also found a strong relationship between colony loss and a broad category of beekeeping practices noted on a USDA survey as "other," which contained everything from hives being destroyed, to food scarcity for bees, to queen failure. They noted that collecting this data in more detail and breaking up this catch-all type variable into smaller categories would improve their ability to identify links between particular stressors and colony collapses.



“A changing climate and high-profile extreme weather events like Hurricane Ian – which threatened about 15 percent of the nation’s bees that were in its path as well as their food sources – are important reminders that we urgently need to better understand the stressors that are driving honey bee colony collapse and to develop strategies to mitigate them,” said Francesca Chiaromonte, professor of statistics and the holder of the Lloyd and Dorothy Foehr Huck Chair in Statistics for the Life Sciences at Penn State and a senior member of the research team.&nbsp;



“Our results highlight the role of parasitic mites, pesticide exposure, extreme weather events, and overwintering in bee colony collapse,” she concluded. “We hope that they will help inform improved beekeeping practices and direct future data collection efforts that allow us to understand the problem at finer and finer resolutions.”



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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What is causing honey bee colony collapse in the U.S.?

Honey bees are crucial pollinators of flowers, enabling the plants...

Rapid climate change is forcing many species to evolve and adapt quickly enough to avoid extinction, particularly those that do not tolerate a large degree of environmental variation, such as species from cooler high-elevation habitats, which often lack the genetic diversity that is crucial for adapting to global warming.



According to a new study led by <a href="https://www.flinders.edu.au/">Flinders University</a> in Australia, <a href="https://www.earth.com/news/hybridization-among-wild-baboons-comes-with-hidden-costs/">hybridization</a> – the process of mixing different species – could potentially help the most vulnerable ones adapt and rapidly exploit novel genetic diversity from species that are already adapted to warmer environments. This concept is similar to how the historic mixing between our ancestors and Neanderthals seems to have improved the fitness of some modern human populations.



To test this hypothesis, the scientists traveled to the Wet Tropics region of northeastern Australia to collect samples of five species of tropical rainbowfish along an elevation gradient. Genetic analysis of the samples revealed both pure and hybrid populations of rainbowfish, and helped the researchers identify genes that enable rainbowfish populations to adapt to climate variation.



More specifically, the populations of cool-adapted upland species that have hybridized with a warm-adapted lowland species showed reduced vulnerability to future warming scenarios. “These mixed populations contain more diversity at genes we think are important for climate adaptation, and are therefore more likely to persist in warmer environments,” explained study lead author Chris Brauer, a research fellow in Landscape Genomics at Flinders University.&nbsp;



These findings highlight the underappreciated conservation value of hybrid populations, suggesting that hybridization may facilitate rapid adaptation to climate change. “Our findings are good news for biodiversity. They indicate that genetic mixing is an important tool for conservation that can contribute to natural evolutionary rescue of species threatened by climate change,” concluded senior author Luciano Beheregaray, a professor of Biodiversity Genomics at Flinders.



The study published in the journal <a href="about:blank">Nature Climate Change</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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Hybridization reduces vulnerability to climate change

Rapid climate change is forcing many species to evolve and...

There has been much research recently exploring the role of the gut microbiome in the health of humans and other <a href="https://www.earth.com/news/can-we-communicate-with-animals-using-artificial-intelligence/">animals</a>. Indeed, mammalian gut microbes have been shown to affect aspects of development, digestion, physiology, metabolism, immunity, mental health and behavior. In addition, individuals with autism or autistic-like behaviour are known to have altered gut microbe communities. Thus, the relationship between the microbiome and behavior is reciprocal, since social interactions can influence the gut microbiome, which in turn can affect social behavior.



With these connections in mind, researchers from the University of Oxford, U.K., and the University of Boulder, Colorado, set out to investigate the relationship between the gut microbiome and the social behavior of wild rhesus macaque monkeys (Macaca mulatta) on the island of Cayo Santiago, off Puerto Rico. In particular, they wondered whether monkeys with better social networks have healthier gut microbiomes compared to individuals that are less connected.&nbsp;



Macaques have an Asian origin and are found in many countries, including India, Thailand, China, Pakistan, Nepal, Bangladesh, and Vietnam. A group of 409 was introduced onto the 15.2 ha island of Cayo Santiago in 1938, and their behavior and social relationships have been studied there ever since. They live in social groups composed of a few adult males and many adult females and their offspring, and grooming is their primary means of making and maintaining relationships. Grooming interactions are thus a good indicator of social connectedness between individuals.



In this study, published in the journal <a href="http://dx.doi.org/10.3389/fmicb.2022.1032495">Frontiers in Microbiology</a>, 50 uncontaminated fecal samples were collected from a specific group of macaques between 2012 and 2013. The group consisted of 22 males and 16 females between the ages of six and 20 years. Social connectedness between group members was measured in terms of the time each monkey spent grooming or being groomed during this two-year period, as well as his or her number of grooming partners. In this way, the researchers could correlate social connectedness with the gut microbiome composition of the monkeys in the group.&nbsp;



“Macaques are highly social animals and grooming is their main way of making and maintaining relationships, so grooming provides a good indicator of social interactions," explained study co-author Dr. Karli Watson from the Institute of Cognitive Science at CU Boulder.



DNA analysis of gut microbes was conducted by the researchers to find out how microbiome diversity within and between macaques was related to grooming interactions, whilst controlling for the effects of rank, sex, age, season and sampling year. The results showed that gut microbiome composition differed considerably between individuals in the group, as did the extent of social interactions.&nbsp;



Specifically, the amount of grooming an individual received was a significant factor explaining differences in microbiome composition between macaques. Put simply, monkeys that had more friends who groomed them also had more gut microbes associated with healthy functions, and fewer microbes associated with disease.&nbsp;



“Engagement in social interactions was positively related to the abundance of certain gut microbes with beneficial immunological functions, and negatively related to the abundance of potentially pathogenic members of the microbiota,” said co-author Dr. Philip Burnet, a professor in the Department of Psychiatry at the University of Oxford.



For example, genera more abundant in the most sociable monkeys included Faecalibacterium&nbsp;and&nbsp;Prevotella. Conversely, the genus&nbsp;Streptococcus, which in humans can cause diseases such as strep throat and,&nbsp;pneumonia, was most abundant in less sociable monkeys.



Lead author Dr. Katerina Johnson, a research associate at the Department of Experimental Psychology and the Department of Psychiatry of the University of Oxford, said: “Here we show that more sociable monkeys have a higher abundance of beneficial gut bacteria, and a lower abundance of potentially disease-causing bacteria. It is particularly striking that we find a strong positive relationship between the abundance of the gut microbe&nbsp;Faecalibacterium&nbsp;and how sociable the animals are.&nbsp;Faecalibacterium&nbsp;is well known for its potent anti-inflammatory properties and is associated with good health.”



These findings are also consistent with findings in human populations where autism is associated with an altered gut microbial community. Autistic individuals engage in less social contact and it is possible that limited social interactions influence the gut microbiome negatively. However, the converse may also be true, namely that a distinctly altered gut microbiome may affect behavioral traits and, therefore, sociability. In this way, it is possible that the relationship between these two variables is indeed reciprocal.&nbsp;



Although none of the monkeys in the test group was classified as autistic, some were more sociable than others, and took part in more grooming activities. Just as in human society, some individuals show more social behavior while others are more isolated. Grooming in macaques involves hand-to-mouth actions and this undoubtedly affects the microbial community in the gut. Previous research has shown that grooming leads to increased similarity in the gut microbiomes of individual monkeys in social groups.&nbsp;



“The relationship between social behavior and microbial abundances may be the direct result of social transmission of microbes, for example through grooming. It could also be an indirect effect, as monkeys with fewer friends may be more stressed, which then affects the abundance of these microbes. As well as behavior influencing the microbiome, we also know it is a reciprocal relationship, whereby the microbiome can in turn affect the brain and behavior,” said Johnson.



"As our society is increasingly substituting online interactions for real-life ones, these important research findings underline the fact that as primates, we evolved not only in a social world but a microbial one as well," said study co-author Dr. Robin Dunbar, a professor from the Department of Experimental Psychology at the University of Oxford.



The authors conclude: “Our findings advance our understanding of how gut microbial communities may be associated with host behavior and reveal that social relationships may be intertwined with health and immune status&nbsp;via&nbsp;the microbiota.”



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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Can close friendships improve our gut health?

There has been much research recently exploring the role of...

Fleeing is not the only way in which <a href="https://www.earth.com/news/songbirds-have-some-impressive-cognitive-skills/">songbirds</a> protect themselves from predators. Many species are known to engage in mobbing too, a phenomenon where they gather aggressively around a predator, flying rapidly while producing loud vocalizations and stereotypic movements. Such a behavior is risky for both prey and predator, with some birds getting attacked and even injured by their mobbers.



Now, a team of researchers from <a href="https://oregonstate.edu/">Oregon State University</a> (OSU) has found that songbirds can tell when the risk of predation by a common predator is higher, depending on season and geographical features, and increase the frequency of mobbing behavior. By contrast, when the risk is minimal, they are more likely to avoid or ignore the predator.



“Mobbing must be energetically costly, because we find that its rare during winter, when food is scarce but there are still plenty of songbirds around,” said study co-author W Douglas Robinson, an ornithologist at OSU.



“On top of this effect, the likelihood of mobbing also increased as the number of songbirds present increased, diluting the risk to each mobber. Thus, songbirds can assess when the risk of predation from northern pygmy owls is highest and when there is safety in numbers.”



The experts studied mobbing of northern pygmy owls (Glaucidium gnoma) – a small, diurnal own species that usually attacks small mammals and songbirds by ambushing them from a hidden location - in western Oregon.&nbsp;



“The proportion of small birds relative to small mammals in the diet of the northern pygmy owl almost doubles from spring to summer, making birds the primary food source in summer. This is presumably because of the increasing availability of fledged offspring birds,” explained study lead author Madeleine Scott, a graduate student in Fisheries and Wildlife Conservation at OSU.



In 2020 and 2021, the scientist played back hundreds of recordings of an advertising call of the northern pygmy owl at a variety of locations to provoke mobbing. Before and after each playback, they recorded the number of species of songbirds present within 50 meters from the speaker.&nbsp;



While overall, mobbing was observed in 8.1 percent of the trials, the behavior peaked (up to 23 percent) in late summer and autumn when the owls prey mostly on young birds, and was quite rare in spring and winter (one percent), when they usually hunt small mammals. Moreover, the probability of mobbing also decreased with altitude, correlating with the lower owl density at higher altitudes. Twenty-four species of songbirds engaged in mobbing, the most frequent ones being chickadees, red-breasted nuthatches, Pacific wrens, and dark-eyed juncos.



According to the researchers, songbirds only mob if the threat is real and there are enough songbirds around to dilute the risk.



“Future research questions should study how the energetic cost of mobbing impacts the frequency of the behavior. For example, examining seasonal food availability and supplementing with additional feeders could reveal the how energetic considerations influence mobbing behavior,” Scott concluded.



The study is published in the journal <a href="http://dx.doi.org/10.3389/fevo.2023.1092323">Frontiers in Ecology and Evolution</a>.&nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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Songbirds use mobbing behavior to deter predatory owls

Fleeing is not the only way in which songbirds protect...

Underwater,Funny,Photo,Of,Golden,Labrador,Retriever,Puppy,In,Swimming

Scientists have long known that playing sports can be highly beneficial for mental well-being in humans. Now, a team of researchers led by <a href="https://www.tufts.edu/">Tufts University</a> and the <a href="https://www.centerforcaninebehaviorstudies.org/">Center for Canine Behavior Studies</a> in Connecticut has discovered that <a href="https://www.earth.com/news/dogs-are-more-aware-of-actions-than-objects/">dogs</a>’ anxiety levels can be lowered by social exercising too. The study revealed that canines suffering from generalized anxiety disorders which took part in sporting activities were more likely to get better.



The researchers examined a cohort of 1,308 dogs with at least one type of fearful or anxious behavior. Of these, 273 were diagnosed with generalized anxiety disorder, a condition in which dogs – as well as other animals, including humans – exhibit constant or near-constant anxiety regardless of the context, a phenomenon significantly impairing their quality of life.



According to Nicholas Dodman, an expert in Animal Behavior at Tufts, dogs “especially benefit from activities that feed into their natural instincts.” For instance, a sheepdog suffering from anxiety disorders was significantly helped after starting sheep-herding classes. “The dog was a nervous wreck. I suggested to the owner to take him to sheep-herding classes. After several trials herding real sheep he settled right down. His anxious behavior was gone,” Professor Dodman reported.



Other sporting activities that were found to be beneficial for anxious dogs included Flyball (a type of relay race with teams of dogs), agility courses, and “canine freestyle,” in which dogs are taught to dance to choreographed routines with their owners.



“Dog-sporting activities were highly effective for treating generally anxious dogs, with just over three times the odds of improvement,” the researchers wrote.&nbsp;“The reason for the beneficial effect of engaging in sporting activities may be because of the physiological benefits of mobilization but also the psychological aspects of social integration, accomplishment and enjoyment.”&nbsp;



The study is published in the <a href="https://www.sciencedirect.com/journal/journal-of-veterinary-behavior">Journal of Veterinary Behavior</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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Anxious dogs can benefit from sporting activities

Scientists have long known that playing sports can be highly...

There is a special relationship between the local net-casting fishers and a group of wild Lahille’s bottlenose <a href="https://www.earth.com/news/dolphins-may-also-suffer-from-alzheimers-disease/">dolphins</a> (Tursiops truncatus gephyreus) that inhabit the coastal region around the city of Laguna, on the south Atlantic coast of Brazil. This association dates back generations and involves dolphins that enter the bay and help drive schools of mullet towards fishers that wait eagerly on the shore with their throw-nets. Although it is well known that the fishers benefit from this help, the reason why the dolphins behave in this way had not been scientifically tested.



However, the results of a long-term study by researchers on this unusual alliance have now been published in the <a href="https://www.jstor.org/journal/procnatiacadscie">Proceedings of the National Academy of Sciences</a>. The researchers collected data on the co-operative fishing that takes place in the bay by combining drones, hydrophones and underwater cameras to capture the details of the partnership. They also conducted long-term demographic surveys of the dolphins and interviewed and observed the fishers.&nbsp;



The study was led by Mauricio Cantor of the Marine Mammal Institute at <a href="https://oregonstate.edu/">Oregon State University</a>. “We knew that the fishers were observing the dolphins’ behavior to determine when to cast their nets, but we didn’t know if the dolphins were actively coordinating their behavior with the fishers,” said Cantor.



“Using drones and underwater imaging, we could observe the behaviors of fishers and dolphins with unprecedented detail and found that they catch more fish by working in synchrony. This shows that this is a mutually beneficial interaction between the humans and the dolphins.”



The traditional, net-casting fishers and the dolphins are both after the same fish for food - shiny, fat mullet. The fishers don’t even bother to throw their nets if there are no dolphins present; instead, they simply stand in the shallows, waiting for dolphins to arrive. The fishers recognize each dolphin and refer to it by name. The dolphins drive the mullet closer to the waiting fishers and, when a group of mullet is close enough, the dolphins signal – with a slap of the tail or a specific dive – and the fishers cast their nets.&nbsp;



Catches of mullet in this bay are far bigger than in other areas where dolphins do not help. Furthermore, the researchers found that the dolphins benefit because, as a net hits the surface, the fish respond by turning away from it, dashing to escape it - straight into the mouths of the waiting dolphins. In this way, dolphins in this group catch more fish and shown a 13 percent increase in survival rates, when compared to populations of non-cooperative dolphins.



Synchronous fishing, between these two top predators, is thus beneficial to both parties. The practice is considered a cultural tradition in the city of Laguna, where it has occurred for more than 140 years and has been passed down through generations of fishers and dolphins. The cooperative fishing relationship is specific to this population of dolphins is not a genetic trait in the animals, but is learned, Cantor said.



“From the fishers’ perspective, this practice is part of the culture of the community in all kinds of ways,” Cantor explained. “They acquire skills passed down from other fishers, and knowledge is spread through social learning. They also feel connected to this place and have a sense of belonging to the community.”



Sadly, the practice is in decline and may well cease to exist if populations of mullet decrease, or future generations of fishers lose interest in learning the art of this unique fishing practice. There are historical and recent accounts of similar behaviors in a handful of locations elsewhere in the world, but the practice is becoming less common or has disappeared completely in most places. The rare nature of the practice is one reason it is being considered for a cultural heritage designation in Brazil, he said.



Predictive models run as part of the study show that the future of the practice could be threatened in the Laguna area as well, if fish populations decline. “The practice is unlikely to continue if either the dolphins or the fishers no longer benefit from it,” said co-author Professor Damien Farine of the University of Zurich and the Australian National University.



Professor Fábio Daura-Jorge of the Universidade Federal de Santa Catarina, Brazil said researchers are already seeing early signs of decline in the practice. “If we take steps to document and conserve the knowledge and the culture of the practice, we can indirectly and positively impact the biological aspects, as well."



The experts suggest that conservation action is needed to ensure the future of the practice. Both the dolphins and the fishers are reliant on a strong and healthy fish population for the cooperative relationship to succeed. In recent years, the region has seen reduced availability of fish. There is also reduced interest in learning the tradition, said Daura-Jorge, who has been monitoring this population for the past 15 years.&nbsp;



“We don’t know what is going to happen in the future, but our best guess, using our best data and best models, is that if things keep going the way they are right now, there will be a time when the interaction will no longer be of interest by at least one of the predators - the dolphins or the fishers,” said Daura-Jorge. &nbsp;



The researchers noted that several conservation measures may be necessary to secure the future of the practice. The first is to try to identify the source of the mullet decline and take measures to better manage that species, such as reducing use of illegal nets through law enforcement, said Daura-Jorge.



Second, the researchers recommend steps to work with current and future artisanal fishers, stressing the cultural and economic importance of the net-casting practice. That might include offering incentives to encourage the traditional practice, such as setting a premium price for fish caught with this method.



“This phenomenon of mutually-beneficial interaction between wildlife and humans is getting more and more rare, and seems to be at global risk,” said Cantor. “The cultural value and the biological diversity are important, and it’s important to preserve it.”



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer



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Brazilian fishers and dolphins benefit from fishing together

There is a special relationship between the local net-casting fishers...

Acaulis rosae

Taxonomic tree: