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Motion Camouflage: The Remarkable Hunting Tactics of Trumpetfish

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Monday, April 8, 2024

Research reveals that trumpetfish stealthily hunt by camouflaging themselves behind other fish like parrotfish, deceiving their prey, damselfish, in a novel survival strategy that may become more widespread due to coral reef degradation.An experiment on coral reefs provides the first evidence that predators use other animals for motion camouflage to approach their prey without detection.A new study provides the first experimental evidence that the trumpetfish, Aulostomus maculatus, can conceal itself by swimming closely behind another fish while hunting – and reduce the likelihood of being detected by its prey.In this ‘shadowing’ behavior, the long, thin trumpetfish uses a non-threatening species of fish, such as parrotfish, as camouflage to get closer to its dinner. This is the only known example of one non-human animal using another as a form of concealment.The research involved hours of diving in the Caribbean Sea, pulling hand-painted model fish along a wire.VIDEOThe long thin trumpetfish uses a bigger, non-threatening species of fish, such as parrotfish, as camouflage to get closer to its dinner without being detected. Credit: Sam Matchette“When a trumpetfish swims closely alongside another species of fish, it’s either hidden from its’ prey entirely, or seen but not recognized as a predator because the shape is different,” said Dr. Sam Matchette, a researcher in the University of Cambridge’s Department of Zoology and first author of the study.Damselfish, Stegastes partitus, form colonies on the seafloor and are a common meal for trumpetfish. Working amongst the coral reefs off the Dutch Caribbean island of Curaçao, researchers set up an underwater system to pull 3D-printed models of trumpetfish on nylon lines past colonies of damselfish, and filmed their responses.VIDEODamselfish inspected the model trumpetfish — and rapidly fled from this predator to avoid being eaten. Credit: Sam MatchetteWhen the trumpetfish model moved past alone, damselfish swam up to inspect – and rapidly fled back to shelter in response to the predatory threat.When a model of a herbivorous parrotfish, Sparisoma viride, moved past alone, the damselfish inspected and responded far less.When a trumpetfish model was attached to the side of a parrotfish model – to replicate the shadowing behavior of the real trumpetfish – the damselfish responded just as they had to the parrotfish model alone: they had not detected the threat.Matchette said: “I was surprised that the damselfish had such a profoundly different response to the different fish; it was great to watch this happening in real time.”The study, involving collaborators at the University of Bristol, is published in the journal Current Biology.Damselfish didn’t detect a threat when the two models passed by together. Credit: Sam Matchette“Doing manipulative experiments in the wild like this allows us to test the ecological relevance of these behaviors,” said Professor Andy Radford in the University of Bristol’s School of Biological Sciences, and coauthor of the study.Matchette, along with his co-author and dive buddy Christian Drerup, spent hours underwater, barely moving, to conduct their experiment.Their earlier questioning of divers working at dive shops in the Caribbean revealed that trumpetfish are commonly seen swimming alongside parrotfish and other reef fish – but the reason for this remarkable behavior had not been tested.In addition, divers were much more likely to have seen the shadowing behavior on degraded, less structurally complex reefs.The researchers spent hours underwater pulling model fish along a wire past colonies of damselfish, and filming their responses. Credit: Sam MatchetteCoral reefs around the world are being degraded due to the warming climate, pollution, and overfishing. The researchers say the strategy of hiding behind other moving fish may help animals adapt to the impacts of environmental change.“The shadowing behavior of the trumpetfish appears a useful strategy to improve its hunting success. We might see this behavior becoming more common in the future as fewer structures on the reef are available for them to hide behind,” said Dr. James Herbert-Read in the University of Cambridge’s Department of Zoology, senior author of the study.Human duck hunters historically hid behind cardboard cut-outs of domestic animals – called ‘stalking horses’ – to approach ducks without being detected. But this strategy has received little attention in non-human animals and has never been experimentally tested before.Reference: “Predatory trumpetfish conceal themselves from their prey by swimming alongside other fish” by Samuel R. Matchette, Christian Drerup, Isla Keesje Davison, Stephen D. Simpson, Andrew N. Radford and James E. Herbert-Read, 7 August 2024, Current Biology.DOI: 10.1016/j.cub.2023.05.075

An experiment on coral reefs provides the first evidence that predators use other animals for motion camouflage to approach their prey without detection. A new...

Trumpetfish

Research reveals that trumpetfish stealthily hunt by camouflaging themselves behind other fish like parrotfish, deceiving their prey, damselfish, in a novel survival strategy that may become more widespread due to coral reef degradation.

An experiment on coral reefs provides the first evidence that predators use other animals for motion camouflage to approach their prey without detection.

A new study provides the first experimental evidence that the trumpetfish, Aulostomus maculatus, can conceal itself by swimming closely behind another fish while hunting – and reduce the likelihood of being detected by its prey.

In this ‘shadowing’ behavior, the long, thin trumpetfish uses a non-threatening species of fish, such as parrotfish, as camouflage to get closer to its dinner.

This is the only known example of one non-human animal using another as a form of concealment.

The research involved hours of diving in the Caribbean Sea, pulling hand-painted model fish along a wire.


The long thin trumpetfish uses a bigger, non-threatening species of fish, such as parrotfish, as camouflage to get closer to its dinner without being detected. Credit: Sam Matchette

“When a trumpetfish swims closely alongside another species of fish, it’s either hidden from its’ prey entirely, or seen but not recognized as a predator because the shape is different,” said Dr. Sam Matchette, a researcher in the University of Cambridge’s Department of Zoology and first author of the study.

Damselfish, Stegastes partitus, form colonies on the seafloor and are a common meal for trumpetfish. Working amongst the coral reefs off the Dutch Caribbean island of Curaçao, researchers set up an underwater system to pull 3D-printed models of trumpetfish on nylon lines past colonies of damselfish, and filmed their responses.


Damselfish inspected the model trumpetfish — and rapidly fled from this predator to avoid being eaten. Credit: Sam Matchette

When the trumpetfish model moved past alone, damselfish swam up to inspect – and rapidly fled back to shelter in response to the predatory threat.

When a model of a herbivorous parrotfish, Sparisoma viride, moved past alone, the damselfish inspected and responded far less.

When a trumpetfish model was attached to the side of a parrotfish model – to replicate the shadowing behavior of the real trumpetfish – the damselfish responded just as they had to the parrotfish model alone: they had not detected the threat.

Matchette said: “I was surprised that the damselfish had such a profoundly different response to the different fish; it was great to watch this happening in real time.”

The study, involving collaborators at the University of Bristol, is published in the journal Current Biology.

Trumpetfish Using Parrotfish As Motion Camouflage

Damselfish didn’t detect a threat when the two models passed by together. Credit: Sam Matchette

“Doing manipulative experiments in the wild like this allows us to test the ecological relevance of these behaviors,” said Professor Andy Radford in the University of Bristol’s School of Biological Sciences, and coauthor of the study.

Matchette, along with his co-author and dive buddy Christian Drerup, spent hours underwater, barely moving, to conduct their experiment.

Their earlier questioning of divers working at dive shops in the Caribbean revealed that trumpetfish are commonly seen swimming alongside parrotfish and other reef fish – but the reason for this remarkable behavior had not been tested.

In addition, divers were much more likely to have seen the shadowing behavior on degraded, less structurally complex reefs.

Researchers Dive Caribbean Coral Reef

The researchers spent hours underwater pulling model fish along a wire past colonies of damselfish, and filming their responses. Credit: Sam Matchette

Coral reefs around the world are being degraded due to the warming climate, pollution, and overfishing. The researchers say the strategy of hiding behind other moving fish may help animals adapt to the impacts of environmental change.

“The shadowing behavior of the trumpetfish appears a useful strategy to improve its hunting success. We might see this behavior becoming more common in the future as fewer structures on the reef are available for them to hide behind,” said Dr. James Herbert-Read in the University of Cambridge’s Department of Zoology, senior author of the study.

Human duck hunters historically hid behind cardboard cut-outs of domestic animals – called ‘stalking horses’ – to approach ducks without being detected. But this strategy has received little attention in non-human animals and has never been experimentally tested before.

Reference: “Predatory trumpetfish conceal themselves from their prey by swimming alongside other fish” by Samuel R. Matchette, Christian Drerup, Isla Keesje Davison, Stephen D. Simpson, Andrew N. Radford and James E. Herbert-Read, 7 August 2024, Current Biology.
DOI: 10.1016/j.cub.2023.05.075

Read the full story here.
Photos courtesy of

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Meat has a distinct taste, texture and aroma − how do plant-based alternatives mimic the real thing?

A biochemist explains how plant-based proteins are able to impersonate meats and other animal proteins

When you bite into a juicy hamburger, slice into the perfect medium-rare steak or gobble down a plateful of chicken nuggets, your senses are most likely responding to the food's smell, taste, texture and color. For a long time, these four attributes set meat apart from other food groups. But in recent years, food companies have started to focus on the development of meat alternatives. Many people believe that transitioning away from meat-heavy diets can help with environmental sustainability as well as improve their own health. The two main focuses of research have been on plant-based meat alternatives and lab-grown meat. Both have interesting challenges. Lab-grown meat requires growing animal cells and generating a meat product. Plant-based meat alternatives use plant materials to recreate animal-like structures and flavors. Major food companies that have generated plant-based meat alternatives that consumers seem to enjoy include Impossible, Beyond Meat, Mosa Meat and Quorn. From a scientific perspective, the development of plant-based meat alternatives is especially intriguing, because food manufacturers and researchers attempt to create products with similar textures, flavors, appearances and nutrient compositions to those juicy hamburgers or tender chicken fingers. As a biochemist who teaches students about how food fuels our bodies, I focus my research on the composition and the production of these products and how they can mimic animal meat is intriguing to me. Animal meats are composed primarily of protein, fat and water, with small amounts of carbohydrates, vitamins and minerals. The animal tissue consumed is typically muscle, which has a distinctive shape made from fibers of protein that are bundled together with connective tissue. The size and shape of the protein fibers influence the texture of the meat. The amount and identity of natural lipids – fats and oils – found within a specific muscle tissue can influence the protein structure, and therefore the flavor, tenderness and juiciness, of the meat. Meat products also have a high water content. Typically, plant-based meat alternatives are made using nonanimal proteins, as well as chemical compounds that enhance the flavor, fats, coloring agents and binding agents. These products also contain more than 50% water. To produce plant-based meat alternatives, the ingredients are combined to mimic animal muscle tissue, and then supplemented with additives such as flavor enhancers. Developing a meat-like texture Most meat replacements are derived from soy protein because it is relatively cheap and easily absorbs both water and fat, binding these substances so they don't separate. Some companies will use other proteins, such as wheat gluten, legumes – lentils, chickpeas, peas, beans – and proteins from seed oils. Since most animal meats include some amount of fat, which adds flavor and texture to the product, plant-based meat alternative manufacturers will often add fats such as canola oil, coconut oil or sunflower oil to make the product softer and tastier. Proteins and fats don't easily mix with water – that's why the ingredients in salad dressings will sometimes separate into layers. When using these components, food manufacturers need to emulsify, or mix them, together. Emulsification is essential to making sure the proteins, fats and water form an integrated network with an appealing texture. Otherwise, the food product can end up greasy, spongy or just plain disgusting. Many vegan meat alternatives also use gelling agents that bind water and fat. They help with emulsification because they contain starch, which interacts strongly with water and fat. This allows for more of a mixed network of the proteins, fats and water, making them meatier and more appealing to consumers. Creating a product with a meatlike texture is not just a dump and stir process. Since animal meat is primarily muscle tissue, it has a unique spatial arrangement of the proteins, fats and water. In order to mimic this structure, manufacturers use processes such as stretching, kneading, folding, layering, 3D printing and extrusion. Right now, the most popular processing method is extrusion. Extrusion is a method by which the dry ingredients – plant proteins and fats – are fed into a machine along with a steady stream of water. The inner part of the machine rotates like a screw, combining the molecules, converting the structure of the plant material from spherical shapes to fibers. Each plant protein behaves differently in the manufacturing process, so some plant-based meat alternatives might use different ingredients, depending on their structures. Adding the savory flavor Although the texture is essential, meat also has a distinctive savory and umami flavor. A set of chemical reactions called Maillard browning helps develop the complex, rich flavor profiles of animal meats while they cook. So, additives such as yeast extracts, miso, mushrooms and spices can enhance the flavor of plant-based alternatives by allowing Maillard reactions to occur. The aroma of cooked meats typically comes from chemical reactions between sugars and amino acids. Amino acids are the basic components of proteins. Lots of research has focused on attempting to replicate some of those reactions. To promote these reactions, alternative meat developers will add browning agents, including specific amino acids such as cysteine, methionine and lysine, sugars and the vitamin thiamin. Adding natural smoke flavorings derived from hickory or mesquite can also give alternative meats a similar aroma.   Eating with the eyes As the first-century Roman lover of food Apicius said, "We eat with our eyes first." That means that even if the texture is perfect and the flavors are on point, the consumer will still decide whether they want to buy and eat the vegan meat by the way it looks. For this reason, food manufacturers will usually develop plant-based meat alternatives that look like classic meat dishes – hamburgers, meatballs, sausages or nuggets. They'll also add natural coloring agents such as beetroot, annatto, caramel and vegetable juices that make plant-based alternatives look more like the color of traditional meat. Plant proteins such as soy and wheat gluten do not brown like animal meat. So, some food manufacturers will increase the proportion of pea and lentil proteins they're using, which makes the meat alternative look more brown while cooking. With some research, it's not too difficult to mimic the structure, texture, flavor and appearance of animal meats. But the question remains: Will people purchase and consume them? It seems people do want plant-based meat. Countries all around the world have increased their demand for these products. In 2023, the global market was over US$7 billion, and it is predicted to grow by almost 20% by 2030. Julie Pollock, Associate Professor of Chemistry, University of Richmond This article is republished from The Conversation under a Creative Commons license. Read the original article.

Animals
Chemicals
Health

Researchers Uncover the Oldest Record of Humans Using Fire in Tasmania, Almost 2,000 Years Earlier Than Previously Known

A new paper reveals how Aboriginal people changed the landscape by burning, demonstrating how similar practices could help manage modern bushfires

The researchers of the paper, Matthew Adeleye, University of Cambridge, and David Bowman, University of Tasmania, study a sediment core. Simon Haberle Today, the island of Tasmania lies across the Bass Strait from southern Australia, but once, the two were connected by a land bridge. When humans first reached Tasmania’s rugged coastlines and mixed forests approximately 40,000 years ago, it was the southernmost place our species had ever settled. The Palawa/Pakana communities—Tasmanian Indigenous peoples—call this island Lutruwita. Now, new evidence from charcoal and pollen provides the earliest known record of humans using fire on Tasmania. The discovery predates the previous oldest evidence of fire use on the island by about 1,700 years and demonstrates how these early Aboriginal communities shaped their environment through fire. In a new study published this month in Science Advances, researchers show these early people used fire to shape and modify Tasmania’s dense and wet forest. By analyzing sediment cores—long, cylindrical samples of dirt that capture environmental conditions across time—scientists were able to analyze the pollen and charcoal that had built up. “They both, surprisingly, went back quite a long way—longer than most other records in the region have been found to go,” says study co-author Simon Haberle, a paleoecologist at the Australian National University, to Cosmos’ Ellen Phiddian. The records also gave a glimpse into how vegetation and fire changed over the past 50,000 years or more, he adds. Researchers analyzed ancient mud from islands that would have been part of the land bridge that linked Australia and Tasmania during the last ice age. The mud showed an increase in charcoal from fires 41,600 years ago, followed by different types of pollen 40,000 years ago, revealing a major change in vegetation. This suggests Aboriginal communities were clearing the forests to create open spaces, potentially for subsistence. “Fire is an important tool, and it would have been used to promote the type of vegetation or landscape that was important to them,” says lead author Matthew Adeleye, a paleoecologist at the University of Cambridge in England, in a statement. It would have helped the early communities manage forests as they migrated. Previously, the oldest known archaeological evidence of humans in Tasmania was from sediment in a cave, where researchers had found charcoal, animal bones and stone tools dating to roughly 39,900 years ago. But the new paper extends that record deeper into the past. The findings are part of a growing body of research showing how fire moved with early human societies wherever they went, says Regan Dunn, a paleobotanist at the Natural History Museum Los Angeles County who wasn’t involved with the study, to Science’s Warren Cornwall. With this research, it’s becoming more clear that humans first leave their mark on the land through fire, followed by changes to the landscape, she tells the outlet. In this case, those landscape changes came through the expansion of fire-adapted plant species, such as eucalyptus trees, concentrated on the wetter, eastern side of the islands in the Bass Strait, Adeleye says in the statement. The burning likely served to create spaces that produce more food or attract animals that could be hunted. The study’s findings fit into the wider context of bushfires occurring across Tasmania and Australia today. As wildfires have raged through the forests, Aboriginal communities and scientists are thinking about ways to manage those disasters. One of these potential strategies includes traditional burning culture. “Cultural fire management practices are integral to our agricultural practices and are medicine for Country,” Zena Cumpston, a Barkandji researcher at the University of Melbourne, wrote in the Conversation in 2020, during the peak of the extreme Australian bushfires from 2019 to 2020, which became one of the most catastrophic fire seasons in the nation’s recent history. Cultural burning could potentially enhance the ecosystem’s health by improving soil quality and promoting growth, per the U.S. National Park Service. It enhances the habitat for plants and animals and makes it more resilient. For Haberle, the information coming from Western science, including this new study, is less of a revelation and more of an affirmation that cultural burning has been essential to the landscape for many thousands of years, he tells Cosmos. He adds that the Palawa/Pakana people “certainly know a lot of this story already.” Get the latest stories in your inbox every weekday.

Animals
Culture
Food

Why Are Urban Turkeys Thriving?

As many wild populations decline, some city dwellers flourish—and may become a source for reintroductions to rural areas

Wild turkeys are causing a stir in cities across the United States. Whether strutting down sidewalks, stopping traffic or foraging in yards, these once-elusive birds are no longer just creatures of the countryside. Now, they’re making themselves at home in urban environments, turning neighborhoods, parks and golf courses into their new stomping grounds. Yet, while urban wild turkeys are thriving, their rural counterparts face mounting challenges. Nationwide, rural turkey populations have declined by about 15 percent, with even steeper drops in some regions—and not because they’re moving to cities for a cushier life. This contrast between urban success and rural struggle raises questions about how to best conserve turkeys—and how urban populations might help their rural kin. Wild turkeys moving into cities is a relatively new phenomenon. Over the past few decades, these large birds have found their way into urban areas like New York City; Madison, Wisconsin; Boston and Berkeley, California. Turkeys are remarkably adaptable, says Sunny Corrao, a wildlife biologist and public engagement coordinator with the New York City Department of Parks and Recreation, who notes that turkeys have now been sighted in all five boroughs there. “A lot of New Yorkers don’t give them enough credit for figuring out how to survive in the city,” she says. The key to their success? Cities provide a surprising range of perks—plentiful food, prime roosting and foraging spots, and safety from predators. Turkeys are omnivores and have a broad diet, says Corrao. City parks and other urban green spaces offer ideal foraging grounds for them with an abundance of lush grass, insects and acorns—all nutrient-rich fare that fuels their growing numbers. A flock of female wild turkeys feed in a backyard in Shorewood Hills, Wisconsin. Anne Readel Beyond food, cities also create edge habitats where forests meet open spaces that provide turkeys with both tree cover for roosting and spread-out areas for foraging, explains David Drake, a wildlife ecologist at the University of Wisconsin-Madison. Urban areas are rich in these patchworked habitats, and by settling into them, wild turkeys have challenged the old assumption that they require vast, uninterrupted tracts of land to thrive, says Drake. “That was the way turkey management was taught to me,” he says, “but now we’re teaching our students that turkeys are pretty resilient, they’re pretty adaptive.” Cities are also relatively safe places for turkeys to live. Human hunters are one of the largest predators for wild turkeys in rural areas, explains Mark Hatfield, national director of science and planning at the National Wild Turkey Federation. In cities, hunting is typically restricted or banned, giving turkeys a reprieve from that pressure. Further, while rural turkeys contend with predators like coyotes and bobcats, their city cousins rarely have to worry about these threats. “We don’t have a lot of those predators in urban areas,” says Drake, “and if we do, there’s so many other things for predators to eat.” Male wild turkeys can become aggressive when courting females during the spring breeding season, which can lead to conflicts with humans in urban areas. Anne Readel One example of how comfortable turkeys have become in cities unfolded this past spring in Manhattan. “There was a female turkey that just randomly showed up on Madison Avenue in Midtown in Manhattan,” recalls Corrao. She became known as “Astoria” by her fans, and birdwatchers flocked to see her as she took up residence in Park Avenue’s large trees and hung out above the entrance to Saks Fifth Avenue, a luxury department store. However, after around a week, she relocated to the quieter Roosevelt Island in the East River between Manhattan and Queens. “They are very capable flyers,” Corrao says. “If they don’t like a spot, they’ll fly somewhere else.” Yet, as wild turkeys settle into urban spaces, they can sometimes cause conflicts. They block traffic, raid gardens, poop everywhere, scratch cars and even chase children, mail carriers and police—reminding their human neighbors that these bold birds are still very much wild animals, not oversized, feathered pets. Regardless, the relatively easy life of urban wild turkeys contrasts starkly with the struggles faced by many rural populations today. Once abundant, wild turkeys throughout the United States are now in decline—a reversal of trends from just a few decades ago. According to Hatfield, wild turkey numbers skyrocketed from 1.3 million to 7 million between the 1970s and early 2000s, thanks to intensive management efforts that relocated turkeys from areas with healthy populations to regions where they had disappeared. However, more recently, populations have declined to around six million birds. While turkey populations are still doing well overall, Hatfield stresses, troubling trends have emerged of populations becoming increasingly unstable across the country, with notable declines in the Southeast and Great Plains. The reasons behind these declines and instability are complex and not fully understood. One major factor, however, appears to be a steep drop in young turkey, or poult, survival. In the past, hens would typically raise three or four poults to adulthood, says Hatfield. But now that number has dropped to just one and a half to two and a half per hen. The decline in poult survival has caused wild turkey populations to fluctuate widely from year to year, resulting in population instability, says Hatfield. A flock of male wild turkeys saunters across a basketball court in Madison, Wisconsin. Anne Readel Hatfield attributes poor poult survival to changing weather patterns and declining forest health. Cooler, wetter springs are challenging for poults, which are highly susceptible to hypothermia, while damp conditions also make hens easier prey by intensifying their scent. At the same time, forests are increasingly fragmented, less actively managed, and under siege from invasive pests like the emerald ash borer and diseases like sudden oak death. “If the health of your forests goes down, the health of your turkey population will go down,” says Hatfield. Wild turkey populations in Kansas have been particularly affected, with populations declining by nearly 60 percent since 2008. Researchers in the state have received around $2 million in funding to investigate the cause of these declines. Led by David Haukos, a wildlife biologist at Kansas State University, the two-year study broadly focuses on understanding wild turkey survival, reproduction and habitat use in the state. “It’s been 25 years since a major research project has been done in Kansas on turkeys, and the landscapes have changed dramatically, as well as the overall environmental conditions,” says Haukos. A painter works unfazed as a male turkey displays to females in a backyard in Shorewood Hills. Anne Readel The Kansas research is part of a larger, nationwide effort to address declining turkey populations. State agencies and universities across the country are investing more in research than ever before to understand the complexities of the turkey declines, notes Hatfield. The findings from these studies will guide state management strategies and support broader conservation efforts in the coming years. However, in the meantime, several states have canceled or shortened wild turkey hunting seasons, reduced bag limits and introduced new permit restrictions to help declining populations. But could the unexpected success of urban wild turkeys also provide insights to help rural populations recover? Surprisingly, urban turkeys are already playing a role in conservation efforts. In Texas, agencies have begun relocating turkeys from cities in states like Rhode Island and Maine to East Texas, where rural populations have sharply declined. According to Hatfield, these relocations have been remarkably successful with low mortality rates, allowing urban birds to give struggling rural populations a much-needed boost while also easing some of the conflicts these birds can cause in cities. Wild turkeys rest on a picnic table in Madison. Anne Readel Beyond these relocations, urban turkeys highlight the species’ remarkable adaptability—a trait that could help rural populations navigate novel challenges. By nesting in city parks and foraging along greenways, urban turkeys demonstrate the flexibility needed to thrive in new, diverse environments. Their success offers valuable insights into how rural turkeys might respond to issues like climate change and altered habitats. Equally significant, urban turkeys are also sparking a connection to nature among city dwellers. And, according to Hatfield, the urban birds could spur broader support for turkey conservation efforts across the country as people learn how these wild birds found their way into cities and flourished. “We want people to understand how they got there,” he says, “why they’re there, and then why they’re thriving.” Get the latest Science stories in your inbox.

Animals
Climate
Conservation

Drugs, hormones and excrement: the polluting pig mega-farms supplying pork to the world

Mexico is a leading international pork producer, but Yucatán residents say the waste oozing from hundreds of enormous hog farms is destroying the environmentThe stink of excrement was the first thing the residents of Sitilpech noticed when the farm opened in 2017. It hung over the colourful one-storey homes and kitchen gardens in the Maya town in Yucatán, and has never left. Next, the trees stopped bearing fruit, their leaves instead covered with black spots. Then, the water from the vast, porous aquifer emerged from the well with a horrible, overwhelming stench.“Before, we used that water for everything: for cooking, for drinking, for bathing. Now we can’t even give it to animals. Today, we have to give the chickens purified water because otherwise they get diarrhoea,” says one resident. “The radishes grow thin and the coriander often turns yellow. This has always been a quiet town, where life was very good until that farm started,” they say. Continue reading...

The stink of excrement was the first thing the residents of Sitilpech noticed when the farm opened in 2017. It hung over the colourful one-storey homes and kitchen gardens in the Maya town in Yucatán, and has never left. Next, the trees stopped bearing fruit, their leaves instead covered with black spots. Then, the water from the vast, porous aquifer emerged from the well with a horrible, overwhelming stench.“Before, we used that water for everything: for cooking, for drinking, for bathing. Now we can’t even give it to animals. Today, we have to give the chickens purified water because otherwise they get diarrhoea,” says one resident. “The radishes grow thin and the coriander often turns yellow. This has always been a quiet town, where life was very good until that farm started,” they say.Sitilpech lies on the edge of the Ring of Cenotes, a vast network of sinkhole lakes and underground rivers formed by a meteorite impact 66m years ago. The pig mega-farm is just under a kilometre from the first home in the town. It is part of a network of between 500 and 800 facilities that have appeared across Yucatán peninsula in the past 20 years, often nestled in the middle of the internationally important Yucatán moist forest. A mega-farm can hold up to 50,000 pigs, packed tightly together in small pens. The urine and excrement, antibiotics and hormone treatments seep out beneath their corrals, and are then dried in open-air waste lakes in the tropical heat.Part of a pig farm run by Kekén in Chapab, Yucatán. Critics say the complexes contaminate local wells. Photograph: Hugo Borges/AFP/Getty ImagesFor those that live around them, the spread of the pig mega-farms is a human and ecological disaster. Some Maya villages in Yucatán are outnumbered by pigs 100 to one. In the rainy season, the farms pump out the pig waste through sprinkler systems; it oozes into the porous limestone watershed which connects the Ring of Cenotes. Local people say that those who drink the tap water fall sick, and there are severe consequences for the area’s biodiversity.“More than 90% of the 800 pig factories estimated to exist in Yucatán operate without any type of environmental permit,” claims Lourdes Medina Carrillo, an environmental lawyer. “These are projects without a record of prior Indigenous consultation, arising from the destruction of forests considered the second most important on the continent, without permits for changes in land use, and with impacts such as water contamination,” she claims.Pigs are transported on a Kekén farm truck in Chapab. Photograph: Hugo Borges/AFP/Getty ImagesFor many residents, the anger is directed at the Mexican pork brand Kekén, the country’s largest pork exporter. Animals supplied to the brand are sold all over the world, feeding markets in South Korea, Japan and the US. Kekén is part of the Kuo Group conglomerate, which includes companies in the automotive and chemical industry. It generated revenue of more than $1.9bn (£1.5bn) last year, with half coming from the pork division.The push into this region of Mexico started with the Nafta free trade agreement but accelerated in the early 2000s after the US health authorities declared Yucatán a zone free of classical swine fever. Export restrictions on pork were removed, and companies quickly moved to take advantage.As the impact of the mega-farms has grown, residents in Sitilpech have resisted them, forming protests in 2023 against the facilities. But in February 2023, they say they were violently repressed by police who stormed a protest camp, beating those present. Other Maya communities have launched legal disputes against Kekén. At least one of those was upheld by the supreme court, after residents of Homún brought a case detailing “grave and irreversible harm to human health and the environment” caused by a 48,000-pig farm, including “contamination of water … emission of noxious air pollution; the spread of dangerous pathogens”.Sitilpech residents join a demonstration to protest against pig farm pollution on World Water Day. Photograph: Mariana Gutierrez/Eyepix Group/Future Publishing via Getty Images“When the company came to settle, we saw how it sadly began to cut down the trees that we take care of so much for beekeeping. They left large areas of devastated land,” allege members of a family from Kinchil, an hour from Yucatán’s capital Mérida. “It was very sad. They cut down trees that were more than 100 years old, which are the ones that benefit us the most when there is drought,” they claim.At the beginning of last year, the federal Mexican environment ministry found that the watershed around farms in Yucatán was saturated with concentrations of nitrogen and phosphorus from the pigs’ excrement.Analysis of water sample from cenotes, springs and wells in Yucatán by scientists, the communities themselves and the Federal Commission for the Protection against Sanitary Risks (Cofepris) has found contamination by E coli and other bacteria. Communities reported an increase in cases of intestinal infections in Yucatán between 2012 and 2019, a period of pig farm expansion.In response, a spokesperson for Kekén says it specialises in pork production of the highest quality and is one of the biggest employers in the Yucatán region. The company says it uses biodigesters to ensure the most efficient water uses, adding that 90% of its facilities are in protected areas for the conservation of biodiversity. They said they provided a range of benefits for local people, including supporting farming in nearby Maya communities.A pig farm in San Antonio Mulix. Industry operators say they are some of the biggest employers in the region. Photograph: Héctor Vivas/Getty Images“The medications, the hormones they give to the pigs, in addition to their excrement, end up in the water. And that water that the industry uses then travels inside the caves, the caverns, the wells through the Ring of Cenotes. This is the common water that nature and communities use for their supply. This pollution breaks all ecological balances, impacts native fauna and flora, causes loss of biodiversity and even an excess of organic matter,” says Medina Carrillo.“This is an extremely serious problem because the aquifer of the peninsula, the wells and cenotes, are interconnected,” she says.Mexico’s new president, Claudia Sheinbaum Pardo, said during her campaign that she would not promote the closure of mega-farms in Yucatán. “I understand that there are regulations for pig farms, there is technology to avoid contamination … the issue is that the regulations are complied with,” she declared in a press conference in March. “This idea that mega-farms must be closed because they pollute, no. There is technology.”

Animals
Waste
Water

Largest great white shark ever caught in Queensland control program was pregnant with four pups

Female almost the length of a shipping container was found dead on a drumline in August, primary industries department has revealedGet our breaking news email, free app or daily news podcastThe largest great white shark ever caught in Queensland’s shark control program died while pregnant with four pups, the primary industries department has revealed.A female white shark was found dead on a shark-catching drumline near Gladstone in August. Queensland’s Department of Primary Industries took samples for research purposes and has been collaborating with researchers interstate, a spokesperson said.Sign up for Guardian Australia’s breaking news email Continue reading...

The largest great white shark ever caught in Queensland’s shark control program died while pregnant with four pups, the primary industries department has revealed.A female white shark was found dead on a shark-catching drumline near Gladstone in August. Queensland’s Department of Primary Industries took samples for research purposes and has been collaborating with researchers interstate, a spokesperson said.At 5.62 metres long, the shark was about a sixth larger than the average female and almost the size of a 20-foot shipping container.It’s not surprising for one to move towards warmer waters in winter months, according to Daryl McPhee, associate professor of environmental science at Bond University.“You wouldn’t expect to see a large white shark that far north in Queensland during summer,” he said.“The usual range is from about Harvey Bay, Bundaberg, southern Queensland through New South Wales, Victoria, Tasmania [and] New Zealand.”About 750 adult white sharks live along Australia’s eastern shoreline but they are rarely caught on drumlines, McPhee said.Rising numbers of sharks have been caught in Queensland in 2024, with the 1,206 reported so far well above the 958 recorded in 2023. The two decades prior saw fewer than 800 sharks caught each year.The state’s shark control program has run since 1962, and aims to reduce the risk of shark bites in Queensland coastal waters.Changing environmental conditions and new equipment used by the program may be responsible for the rising catches, especially around Gladstone and the Capricorn Coast, the department said.The species targeted by the program, including bull sharks, white sharks and tiger sharks, are euthanised after being caught on drumlines, a policy that has attracted criticism from animal welfare campaigners including Leonardo Guida.“This magnificent female that was nearly six metres long, she only had to be a couple of hundred kilometres further south, and even if she was alive she would have been shot dead,” Guida, from the Australian Marine Conservation Society, said.Sharks caught within the Great Barrier Reef marine park – like the 5.62 metre female – are not killed but instead are tagged and released once they are found.However, sharks can die if they are left unfound on a drumline hook for too long, according to Guida, a shark scientist with the Australian Marine Conservations Society.It is not known how long the 5.62 metre shark had been caught on the line. Another 17 sharks also died after being caught on a drumline in the Great Barrier Reef marine park lines in August, Queensland government data showed.“If Queensland had already transitioned to fully non-lethal shark bite mitigation strategies that are backed by evidence, this shark wouldn’t be dead, pure and simple, and this beautiful giant would still be roaming our oceans,” Guida said.The state is trialling drumlines that send digital alerts, which Guida said could made a difference and ensure sharks like the pregnant female were found and released in time.“You just don’t really come across them that big very often,” he said. “It is incredibly sad.”

Animals
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