Before giant manta rays (Mobula birostris) can grow to up to 30 feet long and 4,409 pounds, they must start small like most living things. Giant manta ray babies (called pups) in Central America don’t have their size to protect them from orca whales (Orcinus orca) and the numerous sharks in the open ocean. Their solution—sticking to the coast, where there is plenty of food to help them grow and defend themselves. A new study published today in the journal Frontiers in Fish Science details the baby rays’ behavior. 

“We show that manta rays’ lifestyle isn’t a one-size-fits-all behavior. Giant manta rays in Central America undergo a dramatic shift in space use as they mature,” Jeffry Madrigal-Mesén, a study co-author and project leader of Mantas Costa Rica, said in a statement. “Juveniles remained strictly within shallow nearshore waters that serve as coastal refuges, but most of the tracked adults executed long-distance transboundary migrations along the continental shelf break into Central America.”

Where the pups grow

In the study, the team used multiple methods to track and identify mantas at five locations between 2018 and 2025. Acoustic telemetry uses underwater sound pulses to monitor fish movements and allowed the team to track 59 individual rays. With satellite telemetry, transmitters track movement and behavior from a distance and helped the team track large-scale movements of 12 individuals. Lastly, photo identification helped to identify individual manta rays.

“If we hadn’t used all three technologies together, we simply wouldn’t have been able to piece this puzzle together,” explained Madrigal-Mesén. “Combining these tools turned fragmented data into a unified, undeniable story.”

The team ended up with a dataset of over 12,000 detections. The data showed that young mantas (those with a body about 10 feet or less) stick to shallow coastal refuges. In these more shallow spots, the pups have a safe place that doesn’t overlap with their predators’ hunting grounds. They have plenty of food and places to hide, and even get essential services like cleaning from reefs.

“Mature adults can rely on their massive body size and their ability to dive deep to evade threats. But juveniles don’t have that luxury,” said Madrigal-Mesén. “What is truly amazing is seeing how strictly young manta rays stick to coastal waters as long-term refuges. We see the same individuals more often than once a year. In fact, just recently, they were sighted again at the exact same tagging location. It is always a joy to see them again—they have truly become a part of the family.”

By comparison, nine mature mantas in the study went on expansive migrations along the continental shelf break. One manta ray nicknamed Mickey Mouse because of a spot pattern on his belly had movements that suggest the fish also continue to display loyalty to a particular site once they grow up. Unusually approachable for a manta, Mickey Mouse allowed the team tag him multiple times over several years, which provided a continuous dataset. In 2020, he logged 462 acoustic detections at a coastal hub called El Secreto. He returned to the same shelf in 2023, and stayed there for 38 days.

“Nearshore cleaning stations transcend basic hygienic function; they act as primary social hubs where courtship and reproductive interactions take place,” said Madrigal-Mesén. “Returning to a predictable coastal depot allows mature rays to prioritize social and cleaning needs before undertaking large-scale regional migrations.”

Traveling the manta swimway—safely

Once they leave coastal regions, adult manta rays face different dangers. Coastal areas are often legally protected marine reserves, but the open ocean is another story. They no longer have legal protection and are exposed to dangers from industrial fisheries and vessel strikes.

According to the team, this shows that marine protected areas alone are not enough to protect this highly mobile species as it swims across Central America. They say that multi-national “conservation swimways”  that link the domestic juvenile coastal refuges with adult migratory corridors could help keep the endangered rays safe. 

“This study opens a new chapter for manta ray research in Central America,” Madrigal-Mesén concluded. “We hope it sparks fresh enthusiasm and encourages future collaborators to join us in executing the new ideas and research projects we have planned for the conservation of this species.”

The post Baby manta rays stick to the shallows to avoid sharks and orca appeared first on Popular Science.

A 518-million-year-old ambulacrarian fossil from China suggests that the common ancestor of starfish and their relatives was not a burrowing worm; it was probably a tentacled animal that fed from the water around it.

The post Early Cambrian Fossil Rewrites Starfish Family Tree appeared first on Sci.News: Breaking Science News.

As the summer drew to a close, aerial surveyors with the New England Aquarium saw more than 2,000 animals across 15 different marine species in the Northeast Canyons and Seamounts Marine National Monument, southeast of Cape Cod. Among that vast diversity, the team spotted Chilean devil rays (Mobula tarapacana). This ethereal fish is “one of the ocean’s best-kept secrets,” according to the aquarium.

“We rarely see Chilean devil rays on our aerial surveys,” Katherine McKenna, a researcher in the New England Aquarium’s Anderson Cabot Center for Ocean Life, tells Popular Science. McKenna was one of the observers on the team that saw the Chilean devil rays from above. 

“The Monument’s deep sea canyons, complex oceanographic conditions, and productive waters support a remarkable diversity of marine life, especially in the summer months when warm water protruding from the Gulf Stream draws in seasonal visitors like Chilean devil rays,” she says.”

Chilean devil rays, also called sicklefin devil rays, are olive-green- or brown-colored and are found in the planet’s tropics and warm temperature seas. These large fish have an 11- to 12.5-foot-wide wingspan and weigh 715 to 1,100 pounds. They’re named after the country where they were first scientifically documented, and McKenna says that the “devil” was inspired by the horn-shaped cephalic fins around their mouths. They are classified as Critically Endangered on the IUCN Red List, and mainly threatened by by-catch and overfishing.

What’s more, the species is relatively difficult to study. They can travel very far, and they are frequently solitary and usually found offshore. When rays like these are found in a group, however, it’s called a “fever.” One thing we  do know is that Chilean devil rays are the deepest diving ray species. They can dive almost 6,000 feet deep. 

“This is possible due to a specialized network of blood vessels surrounding their brain that allows them to keep their brain warm even at very cold water temperatures at deep depths,” says McKenna.

The post ‘One of the ocean’s best-kept secrets’ spotted near Massachusetts appeared first on Popular Science.

Long before sharks or reptiles ruled the seas, armor-plated fish called placoderms were already experimenting with different jaw designs to crush hard-shelled prey.

The post Devonian Armored Fish Show Multiple Ways to Crush Hard-Shelled Prey appeared first on Sci.News: Breaking Science News.

In French Polynesia, an adult seahorse floats in ocean waters alongside two juveniles. His head appears bowed, as the young fry look on curiously. The captivating black-and-white image (seen below) by photographer Julien Anton took top honors at the 2026 Ocean Photographer of the Year awards.

“Winning Ocean Photographer of the Year is an immense honour – one I’m proud to share with my family, and with the local residents, naturalists and fishermen of Tahiti and Moorea whose knowledge made this image possible,” Anton said in a statement. “We spent countless hours searching in difficult conditions, with no guarantee of finding a single seahorse. That is what made the moment so extraordinary – when the juveniles turned back towards the adult, it felt like something far beyond what I had dared to hope for. I am not a professional photographer; for me, photography is simply how I share what I see and feel. My hope is that this image can serve as a bridge between science, conservation and a world that deserves to know what is at stake.” 

The 2026 Ocean Photographer of the Year competition celebrates Big Blue’s incredible beauty while also highlighting the urgent need to protect it in a rapidly changing world. The annual contest is co-presented by Oceanographic Magazine and Blancpain.

The post 16 splashy and spectacular images from the 2026 Ocean Photographer of the Year awards appeared first on Popular Science.

Paleontologists in Montana have discovered remarkably preserved feathers of an ancient aquatic bird inside a fossilized dinosaur dropping, offering rare insight into why certain birds survived the asteroid strike that wiped out the dinosaurs 66 million years ago.

The post Exceptionally Preserved Bird Feathers Found in 66-Million-Year-Old Dinosaur Coprolite appeared first on Sci.News: Breaking Science News.

The deep-sea is filled with weird creatures: goblin sharks (Mitsukurina owstoni), vampire squid (Vampyroteuthis infernalis), and… walking fish? For the first known time, a team of scientists in China filmed a strange, shrimp-like fish walking backward along the seafloor. 

The fish, Scalicus engyceros, is a species of armored searobin, a group of fish known for  weird anatomy. Their bodies are  covered in bony plates, while stiff free fin rays stick out of its pectoral rays like tiny legs it can use to “walk.” 

The new study, published in the journal Ocean-Land-Atmosphere Research, not only provides video evidence of the animal’s sea-floor strolls, but it also marks the first time backwards locomotion has been described in fish. 

“[Our] study delivers a paradigm-shifting revelation: the deep-sea fish Scalicus engyceros, a representative of fishes characterized by highly specialized free pectoral-fin rays, is among the few fish species known to walk,” said Han Tian, a postdoctoral researcher at Sun Yat-sen University in Guangzhou, in a statement. 

The video was taken from a deep-sea diving vehicle in the northern South China Sea that also helped the researchers observe the fish’s other unique traits. It has outward-extending barbels that resemble a farmer’s rake. While the barbel makes it awkward for the fish to walk, it provides “an advantage in probing, digging, or hunting for food buried in the sediment,” according to the team. 

Like other deep-sea creatures, Scalicus engyceros also has large eyes. The researchers note that the fish did not seem to react to the approaching vehicle, but it did appear to react to its light beam before swimming away. This suggests its eyes have at least some sensitivity to light, perhaps pointing to the fish not having lived in this habitat for very long. 

While there’s still much to learn about this mysterious creature, advancements in technology are helping scientists better understand the life way beneath our oceans’ surface. 

“Modern deep-sea diving vehicles allow not only discovery of new species but also add a new in situ, functional dimension to the study of species based solely on the morphology of preserved specimens,” said Tian. 

“By observing deep sea animals alive in their surrounding environment, we can gain insight into the adaptation and evolution of the species. These walking fish harbor far more novel behavioral and evolutionary adaptations than previously assumed.”

The post Backwards-walking fish caught on video in the South China Sea appeared first on Popular Science.

On June 19, the Aquarium of the Pacific took in almost 500 animals in one go. Fish, marine invertebrates, and sharks were all brought into the facility in Long Beach, California, but the aquarium hadn’t just gone on some big marine shopping spree. 

These animals were rescued from animal trafficking, and were in urgent need of a home. At the aquarium, the staff worked through the night to stabilize and care for them. 

“Every animal that arrives at the Aquarium, whether through a carefully planned acquisition or a last-minute confiscation, receives the same high standard of care. What can differ is the condition in which those animals arrive,” Johnathan Casey, Aquarium of the Pacific curator of fish and invertebrates, tells Popular Science. 

Many trafficked animals have been traveling in stressful or poor conditions, so the aquarium’s experts immediately check their physical condition, water quality, and individual needs. They usually know little about an animal’s origin or history, so the team needs to be prepared for anything. The rescued animals are also quarantined to avoid the potential spread of diseases, according to Alyssa Tillman, the assistant curator of fish and invertebrates. 

The species included brownbanded bamboo sharks (Chiloscyllium punctatum), ocellaris clownfish (Amphiprion ocellaris), and Banggai cardinalfish (Pterapogon kauderni). The IUCN Red List classifies brownbanded bamboo sharks as Near Threatened and Banggai cardinalfish as Endangered. 

While the arrival of almost 500 animals was a standout event, the Aquarium of the Pacific has received rescued animals from over 30 confiscation events since September 2024.  This means they saw one confiscation event every three weeks, though the first eight months of 2026 have already seen over a dozen cases. Overall, the aquarium has taken in over 3,600 rescued trafficked animals in the past two years. 

The Aquarium encourages “the public to become informed consumers to help avoid wildlife trafficking of exotic pets. This includes researching the protected status of the species and ensuring purchases are through a reputable vendor,” Casey explains. “If the vendor cannot provide proof of where the animal came from, refraining from purchasing it is a way to help.” 

The post Nearly 500 animals rescued from trafficking arrive at a California aquarium appeared first on Popular Science.

Marine biologists from Trinidad and Tobago recently completed the first locally helmed and most expansive survey of the deep-sea waters around the Caribbean islands. The month-long project aboard Schmidt Ocean Institute’s research vessel (R/V) Falkor (too) documented around 13 percent of the nation’s marine territory, and described 20 potential new species. Researchers also collected over 700 specimens for the University of the West Indies, St. Augustine. Once catalogued, the additions will increase the size of the university’s Zoology Museum deep ocean collection by 12 times.

“Every new discovery we make, whether ecosystem, species or behavior, deepens our understanding of what’s at stake and strengthens our ability to be true stewards of this largely unseen but critical part of our country,” said expedition chief scientist Diva Amon.

Check out some of the stunning, rarely seen creatures below. (Click to expand images to full screen.)

Suspected new sea star

Symbiotic coral

King crab

Rare manta ray fall

Eelpout

Squat lobster

Mushroom coral

Black swallower fish

Lizard fish

Ghost shark

The post 11 vibrant deep-sea creatures shine in new Caribbean expedition appeared first on Popular Science.

Just like 20-somethings yelling or waving in a crowded, strobe light-filled club, three-spined sticklebacks (Gasterosteus aculeatus) can change their social behavior for the benefit of the group. These small fish will change how they swim to help find food when they are in cloudy water. The findings are detailed in a study published today in the journal Proceedings of the Royal Society B.

There are eight known species of sticklebacks (order Gasterosteiformes). These small fish live in fresh, brackish, and marine waters all over the Northern Hemisphere and as far north as the Arctic Ocean. They can grow to a maximum length of roughly seven inches and are known for a row of two to 16 spines on their backs.

Since they live in everything from salty seas to fresh lakes, their habitats can range from crystal clear to densely clouded. Turbidity is when small particles like mud, algae, or silt make water cloudy. While it is a natural process, farming, mining, construction, and other pollutants are increasing turbidity and reducing visibility in rivers and coastal waters around the world. This can make it more difficult for aquatic animals like sticklebacks to see their food, friends, or enemies.

“At the moment, we’re seeing our weather flipping between hot, dry periods to heavy rains, which mean[s] our rivers and streams experience sudden surges of muddy, highly turbid water,” 

Dr. Sean Rands, a study co-author and behavioral ecologist at the University of Bristol, said in a statement. “It is good to know that the fish can respond to these big changes.”

For this study, the team observed how three-spined sticklebacks responded to their water becoming cloudier and noted their directions when food suddenly appeared in the water. 

In murkier water, the fish took longer to swim towards the food than those in clear water. However, individuals in larger groups responded more quickly in both clear and cloudy water. 

The way that the sticklebacks moved together also influenced their response to the food. The smaller groups living in murky water got to the food more quickly when they swam close together in the same direction. By contrast, tighter coordination slowed the group’s response for larger groups of fish in clear water.

Before the food was introduced, fish in murky water tended to stick closer together, align their movements more closely, and respond more eagerly to the behavior of group members that were nearby.

According to the team, these results suggest that sticklebacks can compensate for reduced visibility in the water by increasing cooperation and coordination with one another. 

“When we put an unexpected piece of food in the water, it took the fish longer to find it when the water was cloudier. This makes sense and has been shown before in different water-living species,” added study co-author and behavioral ecologist Christos Ioannou. “However, we were excited to see that the sticklebacks were able to compensate for this challenge by changing their shoaling behaviour. Their shoals became more coordinated, with the fish moving and aligning themselves together much more closely in poor conditions. This in turn meant the fish were able to find the food faster than if they weren’t coordinating.” 

This enhanced social behavior may help them overcome the challenges of living in murky environments and respond better when there is an opportunity to find a meal. 

“Finding that these rules are able to change in response to the challenges animals experience is reassuring, as it shows that these little fish have some extra tricks for the changes that humans are causing to their homes,” said Rands. 

The post These fish rely on teamwork to find food in murky water appeared first on Popular Science.

Paleontologists studying a fossil unearthed in southern Manitoba, Canada, have identified what they believe are two bite marks on the internal skeleton of the ancient giant cephalopod Enchoteuthis.

The post Fossil of Giant Squid-Like Creature from Cretaceous Period Bears Marks of Deadly Attack appeared first on Sci.News: Breaking Science News.

Temperatures in the Arctic are increasing at a rate 4 times faster than the average global temperature. Scientists have documented the global effects of climate change, but there are still regions where these effects are less well known. This is the case for freshwater ecosystems in the Arctic.  

When the ground has been permanently frozen for 2 years, scientists call it permafrost. Permafrost contains soil, sand, rocks, and organic matter held together by ice. As temperatures rise, permafrost thaws, which can change groundwater flow paths. It can also alter a stream’s temperature, flow patterns, and nutrient loads by introducing new material from the permafrost.  

To determine how thawing permafrost affects Arctic ecosystems, scientists from the U.S. Geological Survey recently studied 10 headwater streams within the Brooks Range in the Noatak National Preserve of Alaska. The scientists studied streams with different amounts of permafrost and ice to test whether connections exist between permafrost, food webs, and populations of fish called the Dolly Varden and Arctic Graylings. They focused on these 2 species of fish because their migrations often indicate ecological shifts in the area.    

The scientists collected fish from the streams by temporarily stunning them, using a method called electrofishing, or by catching them in minnow traps. They manually identified each species they collected, then froze the fish and shipped them to a lab. Once in the lab, the scientists measured the length of each fish and used documented growth patterns to estimate its biomass. To calculate fish abundances, they divided their total biomass by the time spent electrofishing or trapping. Finally, they measured the energy density of each fish by burning it in a device called a bomb calorimeter. 

At each stream, the scientists took manual temperature measurements and deployed loggers that recorded the temperature every 15 minutes. They also deployed equipment at the bottom of each stream to record water pressure in 15-minute intervals and converted the data to depth, since pressure increases with depth. Then, they used wading rods to measure how much water was flowing through each stream at a given spot. 

They combined the depth and wading rod data to determine the flow rate of water in the streams over time. They used these data to identify unstable streams where water rose and fell rapidly. They also collected water samples from each stream and measured their nutrient concentrations, including dissolved organic carbon, nitrogen, and phosphorus, to determine water quality.   

Finally, they measured 2 types of smaller organisms that allow energy to flow through the food web to the fish, called microbial biofilms and macroinvertebrates. They used a hand-held device to estimate the types and amounts of biofilms, and nets to collect macroinvertebrates.

Once they had compiled these data, the team conducted a statistical analysis to compare the studied parameters and fish populations to the extent of permafrost in each area. They found that streams with more permafrost in the area had warmer temperatures, because the permafrost prevented water from infiltrating the soil to cool off. The streams with warmer temperatures, in turn, had lower abundances and biomass of Dolly Varden fish and Arctic Grayling with lower energy densities. They suggested that these results meant that the high temperatures had pushed the fish above their optimum temperature range. 

They also learned that the limited infiltration in permafrost areas caused rainfall to flow straight into the stream. This process created instability as the stream levels rose and fell rapidly. Fish in these unstable streams had lower energy densities, likely due to the harsher environment. 

Areas with greater permafrost also had higher concentrations of dissolved organic carbon and phosphorus, which stimulated the formation of biofilms at the bottom of the food chain. They noted that areas with more biofilms also had more macroinvertebrates and more Dolly Varden biomass. Since the Dolly Varden eats macroinvertebrates, this finding suggested that the lowest levels of the food web shape the health of species higher up. This is called the bottom-up effect, and means that areas with more biofilms and macroinvertebrates will likely have healthier and larger fish populations.  

The scientists explained that knowing how these factors influence Arctic fish populations can help researchers understand how thawing permafrost might affect Arctic ecosystems in the future. They anticipated that their data could help future researchers predict how these and other ecosystems will be impacted by changing landscape dynamics caused by global warming. 

The post Thawing permafrost is affecting fish health appeared first on Sciworthy.

Pawns estreia no Linux com xadrez local, p2p e Stockfish. Veja os recursos e como baixar pelo Flathub.

O post Pawns chega ao Linux com xadrez local, online e motor Stockfish apareceu primeiro em Blog do Edivaldo - Informações e Notícias sobre Linux.

An unexpected transmissible cancer has been detected in North American waterways, prompting new concerns about how the disease developed.

Beginning with discoveries in Lake Memphremagog, a glacial lake spanning both Quebec and Vermont, researchers have found strange black cancerous lesions on fish in the waterways of New England and Canada, revealing an environmental mystery.

University of Vermont researchers announced the startling cancer discovery in a recent paper published in Nature, describing how the cells act similarly to a parasite, transmitting between hosts.

This discovery marks the first time a freshwater species has been identified as afflicted with a transmissible cancer, whose long-term population effects are a major concern.

Fish Cancer

Many questions swirl around this discovery, which go far beyond the specific locations and even species affected—such as how cancer operates and how this transmissible form could have originated.

The first indications that something was amiss came from anglers and biologists who both noticed more brown bullhead catfish with raised black patches coming out of Lake Memphremagog. From their first identifications in 2012 to 2014, the prevalence of the disease increased to one in three of these fish.

These particular catfish are often used as a barometer for environmental health, leading the University of Vermont team to consider a pollution-related pathogen after they had ruled out a viral one. Yet under close examination, they discerned the lesions were something even less expected: a type of skin cancer called melanoma, typically caused by sunlight, and therefore, exceedingly rare in bottom-dwelling fish.

Genetic Research

The melanoma finding set the team on a research course looking to identify whether a genetic mutation had left this catfish population particularly susceptible to skin cancer. What they found was surprising: these cancer cells were more closely related to one another than to their host fish’s healthy cells, suggesting transmission.

These transmissible cancers are extremely unusual, with only three types having been discovered previously. None have been found in freshwater or fish species before this; they have been relegated to Tasmanian devils, dogs, and mollusks.

So far, researchers have only identified the malady in larger, spawning-age fish, leading the team to suspect that transmission occurs during spawning behavior. These events do appear to be a likely candidate, as the fish cluster tightly together in shallow water, providing ample opportunity for physical contact among many fish. Furthermore, due to their lack of scales and bottom-dwelling nature, they are more susceptible to the sediment, which could harbor free-floating cancer cells.

In other species, these transmissible cancers may or may not have devastating population-scale effects. Currently, how the Lake Memphremagog catfish population will fare is unknown, although some fish appear to survive years after the infection is first noted.

The University of Vermont team says that the cancer cannot affect humans, and the lake’s drinking water is safe, but they would caution against eating the cancerous fish.

The Root of Cancer

While the Coventry Landfill is in close proximity to the lake, the cancer is spread evenly along the 32-mile-long lake, instead of concentrating near the landfill. Additionally, water tests show that contamination levels are no higher than those of similar North American waterbodies such as Lake Champlain.

Instead, more concerning than a single source of pollution, the team says they have now discovered this cancer in fish located in other ponds and lakes in this region, none of which were close to pollution sources and had pristine water quality.

The one correlation identified so far is that the cancer cells have high arsenic levels, an element naturally found in the region’s soil in high concentrations. Along with this possible link to a natural cause, the researchers are beginning to suspect that the cancer has existed for quite some time, but has simply gone unrecognized. A potential line of evidence for this hypothesis comes from the journals of Henry David Thoreau, who noted a catfish with a similar condition back in the summer of 1852. He even noted that he had come across the fish disease previously, and again wrote of it in 1858.

“By studying how cancers survive and spread outside their original host, we can learn a great deal about what keeps cancers contained—and what happens when those boundaries break down,” co-author Julie Dragon concluded. “These fish provide an opportunity to look at the evolution of cancer.”

The paper, “Brown Bullhead Catfish Melanoma Represents a Novel Transmissible Cancer,” appeared in Nature on July 22, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.