Animals

A mysterious disease has been turning sea stars into goo since 2013. Now, there’s a leading suspect behind the killings — a bacterium called Vibrio pectenicida, researchers report August 4 in Nature Ecology & Evolution. Knowing the identity of the killer could help scientists protect both captive and wild populations of sea stars.

The disease, known as sea star wasting disease, is characterized by twisted arms, lesions and rapid death. One of the worst hit species is the sunflower sea star (Pycnopodia helianthoides), which lost almost 91 percent of its population — over a billion individuals — to repeated outbreaks in 2015, 2018 and 2023. This decline has consequences for ocean ecosystems, as sunflower sea stars are predators that keep sea urchin populations in check. In their absence, sea urchins have mowed down kelp forests, which absorb atmospheric carbon dioxide and support fish, otters, sea lions and other animals.  More

Aaron Tremper is the editorial assistant for Science News Explores. He has a B.A. in English (with minors in creative writing and film production) from SUNY New Paltz and an M.A. in Journalism from the Craig Newmark Graduate School of Journalism’s Science and Health Reporting program. A former intern at Audubon magazine and Atlanta’s NPR station, WABE 90.1 FM, he has reported a wide range of science stories for radio, print, and digital media. His favorite reporting adventure? Tagging along with researchers studying bottlenose dolphins off of New York City and Long Island, NY. More

Add a little-known species of assassin bugs to the list of animals that can fashion and wield tools. And true to their name, the insects use that tool to draw their prey into an ambush, researchers report May 12 in Proceedings of the National Academy of Sciences.

Found in Thailand and China, Pahabengkakia piliceps is a species of predatory insects called assassin bugs that has a taste for the region’s stingless bees. When researchers at Xishuangbanna Tropical Botanical Garden in China began studying the assassin bugs in 2021, they became intrigued by how P. piliceps hunt. While lying in wait at a hive’s entrance, the assassin bugs use their front legs to proficiently pick off bees that fly by. More

A mysterious disease that has plagued sea stars for more than a decade may have met its match in the fjords of British Columbia.

Sunflower sea stars discovered thriving in the frigid waters suggest that cooler temperatures provide protection from sea star wasting disease, or SSWD. The finding, reported in the April Proceedings of the Royal Society B, is a valuable clue about what causes SSWD in the first place, researchers say.

Sea star wasting disease has stumped scientists since the first big outbreak emerged in 2013 off North America’s Pacific coast. “We initially thought it was a virus, but went back on that, because the data was either flawed or the results couldn’t be repeated,” says Ian Hewson, a marine ecologist at Cornell University who was not involved in the new study. His follow-up research into possible microbial or environmental causes has been inconclusive. More

Despite capturing hearts around the world, the wild axolotl — an aquatic salamander with feathery frills and a soft smile — faces extinction. Fortunately, for both axolotls and their fans, a new conservation method shows promise.

In captivity, axolotls abound as household pets and research subjects. But wild axolotls, endemic to a single lake in Mexico, are critically endangered due to degradation of their native wetlands, with only 50 to 1,000 individuals left in the wild. Introducing captive-bred axolotls to restored and artificial wetlands may be a promising option for conserving these charismatic critters, researchers report April 30 in PLOS One. More

Green sea turtles are adjusting their nesting habits in response to rising global temperatures. Individual females are laying their eggs earlier in the season to cope with warmer conditions, researchers report in the February Proceedings of the Royal Society B.

Scientists have long known that the sex of most turtle species is determined by incubation temperature — higher temperatures give life to females, and lower ones produce males. As climate change drives up temperatures, more females and fewer males are being born, potentially weakening populations. Extreme heat can also be lethal for the eggs.

Marine biologist Mollie Rickwood kneels next to a loggerhead turtle protected nest. The females dig themselves down in the sand using their flippers, then they dig a flask-shaped chamber where they lay eggs.Mollie Rickwood

To understand how turtles are adapting, conservation ecologist Annette Broderick and colleagues analyzed three decades of nesting data from around 600 tagged green turtles (Chelonia mydas) on the beaches of Northern Cyprus. The data included the number of successful hatchlings in each nest and temperatures during incubation. The team found that individual females nested earlier as temperatures rose, laying eggs just over six days earlier, on average, for each 1-degree-Celsius increase.

This is “the first time anyone looked at individual turtles and looked at how they’re changing,” rather than studying nesting behavior at a population level, says Broderick, of the University of Exeter in England. More

A small, rocky island off Iceland is home to the world’s largest breeding colony of Atlantic puffins.

When breeding season is in full swing, around 1.5 million adults pair up and nestle into burrows on the grassy seaside slopes above Heimaey island’s rocky cliffs.

Once chicks hatch, puffin moms and dads devote about six weeks to caring for their babies, bringing meals of small fish and fending off predators such as seagulls. By late August or early September, the pufflings are mature enough to live on their own. Over four to five weeks, throngs of young birds head off to sea. Their instinct is to head for the open ocean, where they will spend most of their lives. They leave in the dark of night to hide from predators, guided by the moon.

Puffin parents care for immature pufflings until they can fly on their own. The downy fluff around the neck of this puffling (right) indicates it’s not yet ready to fledge.Rachel Bennett/iStock/Getty Images Plus

But sometimes fledglings lose their way. Heimaey’s only town got electricity about a century ago. Ever since, dazzled by night lights or swept along in stiff sea breezes, some young puffins have taken a wrong turn — toward town.

Light pollution affects wildlife in perilous ways, disrupting crucial activities from pollination to mating. Some creatures, like these Atlantic puffins (Fratercula arctica), lose their orientation and can’t find their way to the ocean. Some could be attacked by predators; others might starve. Fortunately for these pufflings, the residents of Heimaey have taken a hands-on approach to addressing the problem. More

Like rolling into a gas station during a road trip, whale sharks use oil and gas rigs as a pit stop during their migrations of thousands of kilometers across the oceans. The human-made structures attract marine life — including the sharks’ favorite snack: plankton. But experts worry that this lure could put the endangered behemoths at risk of ship strike or chemical pollution.

Satellite tracking of whale sharks off the coast of western Australia shows how oil and gas platforms influence the movements of these gentle giants, marine ecologist Ben D’Antonio and colleagues report January 18 in Diversity and Distributions. “As they migrate across the ocean, they are stopping over and moving between features to presumably grab an easy meal before continuing with their migration,” says D’Antonio, of the Australian Institute of Marine Science (AIMS) and University of Western Australia in Perth. More