Latest news with #Vibrio pectenicida
Yahoo
4 days ago
- Health
- Yahoo
5 Billion Sea Stars Have Shattered and Died Over the Past 10 Years, Scientists May Finally Know Why
A team of international researchers discovered the cause of a sea-star wasting diseaseNEED TO KNOW The cause of a sea star-wasting disease was determined to be a bacterium known as Vibrio pectenicida The disease causes sea stars to disintegrate to death in a white, goo-like substance An estimated 95% of sunflower sea stars died during the 10-year epidemicAfter an estimated 5 billion sea stars died due to a wasting disease in oceans globally, scientists have identified the root cause of the disease. A team of researchers identified the cause as a bacterium known as Vibrio pectenicida. The team reported its findings this week in Nature Ecology & Evolution. The disease causes starfish to disintegrate into a white, slimy substance. The disease is the largest documented epidemic for a noncommercial species, and it has affected more than 20 species of sea stars along the West Coast of North America, Scientific American reports. An estimated 90% of sunflower sea stars ( known as Pycnopodia helianthoides) have died from the illness, making them a critically endangered species. Sunflower sea stars are capable of sprouting 24 arms and growing to the size of a bicycle tire, per the Associated Press. The epidemic has lasted a decade. The same strain of bacteria has also infected shellfish. The international research project was led by scientists from the Hakai Institute, the University of British Columbia (UBC), and the University of Washington—and conducted in collaboration with The Nature Conservancy, the Tula Foundation, the U.S. Geological Survey's Western Fisheries Research Center, and the Washington Department of Fish and Wildlife. The first author on the study and an evolutionary ecologist at the Hakai Institute and UBC, Melanie Prentice, told Tula: "When we lose billions of sea stars, that really shifts the ecological dynamics.' Prentice went on to describe the impact of losing a sea star. 'In the absence of sunflower stars, sea urchin populations increase, which means the loss of kelp forests, and that has broad implications for all the other marine species and humans that rely on them," she explained. "So losing a sea star goes far beyond the loss of that single species.' Never miss a story — sign up for to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories. With the sharp decline in sea stars, the sea urchins that usually serve as a food source rapidly expanded in population. In turn, they ate nearly 95% of the kelp forests in Northern California within a decade. These kelp forests help provide food and habitats for a wide variety of marine life, including fish, sea otters and seals, per the AP. With these new findings, researchers are hoping to revive the sea star population and restore balance to the ecosystem, the outlet reported. Read the original article on People
Yahoo
6 days ago
- Science
- Yahoo
Study IDs possible cause of sea star wasting disease that wreaked havoc on Oregon Coast
A leading suspect has been identified as a likely cause of sea star wasting disease, which has had a major impact on the ecology of the Oregon Coast over the past decade, according to a study published Aug. 4 in the journal Nature Ecology & Evolution. The bacterium Vibrio pectenicida was identified as being the causative agent in a disease that has killed billions of sunflower sea stars on the West Coast. The finding is critical, the study says, because the discovery "will enable recovery efforts for sea stars and the ecosystems affected by their decline." The loss of sea stars has led to a highly impactful "trophic cascade" in the ecosystem off the coast. Left unchecked by predatory sea stars, the sea urchin population has exploded, which has led to a major decline in nearshore kelp forests that serve as habitat for a wide range of fish and shellfish species. In 2021, the Center for Biological Diversity submitted a petition to list the sunflower sea star under the Endangered Species Act. The National Marine Fisheries Service proposed to protect the species as threatened in 2023 but the listing has not yet been finalized. 'Hats off to the dedicated researchers who've identified what killed billions of these extraordinary sea stars in the Pacific,' said Catherine Kilduff, a senior attorney at the Center for Biological Diversity. 'With this new information, I'm hopeful we'll be able to stop the sunflower sea star's decline and get their populations back up so they're thriving again." Kilduff said the discovery can help entire ecosystems and highlights why research funding and species protection are important. "The federal government needs to stop dragging its feet and provide the safeguards these sea stars desperately need to survive," Kilduff said. Sea star wasting disease first emerged in 2013 along the Pacific Coast and quickly became one of the largest documented marine epidemics ever recorded. Sunflower sea stars, which can grow to 3 feet across and have up to 20 arms, once ranged in high densities from Mexico to Alaska. But they were extremely susceptible to the disease, and after multiple waves of die-offs, have become functionally extinct in their southern range and have lost nearly 91% of its population overall. The identification of the bacterium causing SSWD, conducted between 2021 and 2024, is critical because it could mean treating sea stars in captivity with antibiotics or testing them in the field, Scenice News reported. "You can treat them with antibiotics [that] would target that specific bacteria,' Ian Hewson, a marine ecologist at Cornell University, told the media outlet. Any rebound in their population would be critical. The kelp forests off the Oregon Coast have been disappearing at an alarming rate as the number of sea urchins rises. The forests absorb carbon dioxide and support fish, otters, sea lions and other animals. Zach Urness has been an outdoors reporter in Oregon for 18 years and is host of the Explore Oregon Podcast. He can be reached at zurness@ or (503) 399-6801. Find him on X at @ZachsORoutdoors and BlueSky at This article originally appeared on Salem Statesman Journal: Study IDs possible cause of sea star wasting disease on Pacific coast Solve the daily Crossword
The Guardian
6 days ago
- Health
- The Guardian
Scientists identify bacterium behind devastating wasting disease in starfish
A decade after the onset of a sea star wasting disease (SSWD) epidemic considered the largest ever documented in the wild, researchers have identified the microbial culprit responsible: a strain of the bacterium Vibrio pectenicida. In 10 years the bacterium has ravaged sunflower sea stars (Pycnopodia helianthoides), a large sea star or starfish, along the western coast of North America, with a loss of 5.8 billion since 2013 – or 90% of the total global population. The sunflower sea star is now included on the International Union for Conservation of Nature's red list of critically endangered species. Previous studies had tested for V pectenicida in tissue samples and yielded inconclusive results. Instead, by examining the sea stars' coelomic fluid, which acts like blood, researchers were able to confirm with certainty V pectenicida's role in causing SSWD due to its high abundance there. Infection with the V pectenicida strain FHCF-3 begins with exterior lesions, leading to limb loss and contortion, and ultimately kills afflicted individuals by melting their tissues into a white, mucus-like paste. Identifying the disease in afflicted sea stars was impossible without a known pathogen, as sea stars can respond with similar visual signals to other stressors such as low oxygen, salinity variation and extreme heat. The indirect link between rising ocean temperatures and SSWD remains a key area of interest, since V pectenicida is known to proliferate in warm water during seasonal variations and anomalous marine heating events. The research, published this week in the journal Nature Ecology & Evolution, was led by Dr Melanie Prentice and Dr Alyssa Gehman of the Hakai Institute in British Columbia, Canada, as part of a four-year international collaboration involving the University of British Columbia, the University of Washington and the Nature Conservancy, among other parties. The decline of sunflower sea stars has ramifications for marine ecosystems beyond the loss of a single species. 'Identifying the cause of SSWD is incredibly impactful,' Prentice said. 'In the absence of sunflower stars, [kelp-eating] sea urchin populations increase, which means the loss of kelp forests, and that has broad implications for all the other marine species and humans that rely on them.' Kelp forests provide a habitat for thousands of marine creatures, support local economies through fisheries and recreation, and are culturally important for First Nations and tribal communities. They also stabilise sediments, protect coastlines from storms, and are an important carbon sink for sequestering carbon dioxide. Sign up to Down to Earth The planet's most important stories. Get all the week's environment news - the good, the bad and the essential after newsletter promotion Though the epidemic is still ongoing, the hope is that this breakthrough will aid recovery and treatment efforts for various sea star species across the world and the ecosystems affected by their decline. Methods being explored include captive breeding for resistant individuals and developing probiotic solutions which can be introduced to ecosystems. 'Now that we have found the causative agent of disease, it makes me hopeful that we might actually be able to do something for sunflower sea stars,' says Gehman. 'We can be really targeted in how we work with them, and I think that's going to help us move a lot faster and to try to tackle SSWD.'
Gizmodo
6 days ago
- Science
- Gizmodo
A Mystery Killer Wiped Out Billions of Sea Stars. Biologists Just Solved the Case.
Columbo, eat your heart out: A team of scientists has just solved a massive marine murder mystery, nabbing the culprit behind the deaths of billions of sea stars over the past decade. In a new study, researchers in the U.S. and Canada argue that the bacterial cousin of cholera is behind the epidemic. Through a series of experiments involving both wild and captive sea stars, they found evidence that Vibrio pectenicida is the likely cause of sea star wasting disease—a devastating condition that causes the invertebrates to decay and essentially 'melt.' The team's findings appear to be well supported with evidence, Zak Swartz, a biologist specializing in sea stars at the Marine Biological Laboratory who was not involved with the study, told Gizmodo. 'This study definitely passes the sniff test for me. It seems quite convincing that V. pectenicida bacteria are at least one causative agent of SSWS,' Swartz said. Sea stars started disappearing in 2013, when a massive outbreak of SSWD struck the North American Pacific coast. The disease swept the seas from Alaska to Mexico, decimating more than 20 different species of sea stars, which are also known as starfish. Afflicted creatures first develop visible lesions on their skin, and then their tissue starts to decay. Death by SSWD is often swift, killing the sea star within days. There have been other mass sea star die-offs in recent decades, but the sheer scale and spread of this outbreak makes it possibly the largest marine disease epidemic ever recorded in the wild. Researchers estimate that one particular sea star species, Pycnopodia helianthoides, has lost 90% of its population to SSWD. The destruction has also dramatically changed the environments where the sea stars once thrived. In the aftermath of SSWD outbreaks, some areas have also lost kelp forests, as sea urchins—once kept in check by sea stars—decimated the underwater forests. Marine scientists have been looking for the cause of SSWD ever since its emergence. And like any great mystery, there have been some twists. In 2014, a research team published a paper that argued a sea star-associated densovirus caused SSWD. But subsequent studies showed that this virus—or any potentially pathogenic virus for that matter—could only be found in a minority of affected species, ruling it out as the likeliest suspect. Swartz noted that some Vibrio bacteria, however, were already known to cause disease in echinoderms—the broad group of marine invertebrates that includes sea stars. 'So in a sense, it feels like the answer was hiding right under our noses. It makes total sense,' he said. Several species of Vibrio can also sicken humans, including cholera (Vibrio cholerae). The researchers didn't set out on this study with V. pectenicida in mind from the get-go. They exhaustively studied samples of sea stars with SSWD and healthy specimens, eventually finding that only the diseased sea stars carried high levels of the bacteria in their coelomic fluid (the invertebrate version of blood). The researchers were then able to isolate and grow new populations of the bacteria collected from the sick sea stars. And when they exposed healthy sea stars to these bacteria, the creatures rapidly developed and died from SSWD. These experiments are the same sort used to identify and conclusively show a particular germ causes a specific disease in humans, strengthening the team's case. Further analysis also revealed that SSWD is caused by a specific strain of the bacteria, called FHCF-3. 'Here we use controlled exposure experiments, genetic datasets, and field observations to demonstrate that the bacterium, Vibrio pectenicida strain FHCF-3, is a causative agent of SSWD,' the authors wrote in their paper, published Monday in Nature Ecology and Evolution. Though the mystery of what causes SSWD appears solved, Swartz and the study authors note that there are still several important unanswered questions. For example, scientists aren't sure exactly how the outbreaks start. It's possible the bacteria could spread via sea stars' shared food, or through physical contact with other sea stars. Low levels of the bacteria may also always be circulating in the environment, but only become a major problem under specific conditions, like at a certain temperature (Vibrio bacteria in general thrive in warmer water). Still, given that SSWD remains a threat to sea stars, simply knowing its cause could boost sea star recovery efforts, the researchers said. It might be possible to find genetic mutations that help sea stars fend off these infections, for instance, enabling scientists to breed sea stars carrying these mutations in captivity with the aim of reintroducing them into the wild to bolster the population's resilience.
CTV News
6 days ago
- Science
- CTV News
Canadian researchers solve 12-year mystery of sea star wasting disease
Sunflower sea stars (pycnopodia helianthoides) and sea vases (ciona intestinalis) are seen in the waters in Rivers Inlet, B.C., in an undated handout photo. THE CANADIAN PRESS/Handout - Hakai Institute, Bennett Whitnell (Mandatory Credit) A team led by researchers in British Columbia has solved the mystery of a gruesome disease that has killed billions of sea stars along the Pacific coast of North America, more than a decade after the die off. Melanie Prentice, the lead author of a new study, recalls a moment of 'not really believing it' when researchers found a strain of bacteria that was abundant in diseased sea stars and absent in healthy ones. 'My initial reaction was like, 'Okay, so I've done something wrong,'' she said. Prentice said the team spent months trying to disprove their findings, ultimately confirming they had cracked the code of the disease. They found the bacterium Vibrio pectenicida is a clear cause of sea star wasting disease. '(It's) a question that researchers have been trying to answer for about 12 years, so we're beyond thrilled,' said Prentice, a research associate at the Hakai Institute and the University of B.C. department of earth, ocean and atmospheric sciences. The paper detailing the four-year research project and its findings were published online in the peer-reviewed journal Nature Ecology & Evolution on Monday. Alyssa Gehman, who helped launch the project in 2021, described the disease as 'gruesome,' causing sea stars to develop lesions, lose their arms and 'disappear into mush' about a week or two after exposure to the pathogen. It has been especially deadly for sunflower sea stars, killing about six billion of the species that can sprout 24 arms and span up to a metre. The giant sea stars are now considered functionally extinct across much of their former range off the coast of the continental United States, with losses exceeding 87 per cent in the 'northern refuges' where they still persist, the study said. The collapse has had cascading impacts, including widespread losses of ecologically, culturally and economically important kelp forests. 'I think we didn't really appreciate how important they were until we lost them,' Prentice said, describing the orange, purple or brown sunflower stars as a 'keystone' species with an outsized impact on their ecosystem. The giant sea stars are top predators, striking fear into other invertebrates. 'Almost everything that lives on the ground underwater runs away from them when they're coming,' said Gehman, a marine disease ecologist at the Hakai Institute and an adjunct professor at the University of B.C.'s Institute of Oceans and Fisheries. They keep sea urchin populations in check, in turn ensuring the health of help forests that provide habitat and food for numerous other species. The devastation of the sunflower sea stars has caused a 'total ecosystem shift,' Prentice said, transforming biodiverse kelp forests into 'urchin barrens.' The bacterium that causes sea star wasting disease had remained elusive for more than a decade since sea stars were first observed dying in large numbers in 2013. The same bacterium has been known to attack scallop larvae. Prentice said the breakthrough came after the research team switched from examining diseased tissues to focusing on the sea stars' coelomic fluid, likening it to the blood of the sea star. Earlier research had involved running the tissues through tiny membrane filters that would have excluded bacteria, which are typically larger than viruses, she explained. The Hakai Institute team started by replicating the initial experiments, but they weren't able to cause disease in healthy sea stars, she said. 'We were doing everything we could and we were just never ever able to cause disease, and so to us that suggested that the pathogen is larger than a virus.' However, after pivoting to coelomic fluid, which Prentice described as 'essentially sea water,' the researchers did trigger disease in healthy sea stars. 'That suggested that the pathogen was in that fluid, and so then we just end up working with a much cleaner, easier tissue type to investigate,' she said. From there, Prentice created a list of all the different microbial species found in wasting sea stars and compare it against the healthy stars in the lab. 'I finally got to a place where I generated these different lists and it was very evident right away that there (were) tons of different Vibrio species within our wasting sea stars and we weren't really seeing that in our healthy sea stars,' she said. Prentice said she then filtered the genetic data to look at each strain of Vibrio bacteria, which led to their eureka moment with Vibrio pectenicida. 'We just saw it in every single wasting sea star sample, and then we looked at our controls and it was just not in any of them,' she said. Prentice said other researchers had wished her 'good luck' when she joined the project, but there was skepticism over whether they would solve the mystery. It felt 'incredible' to be part of a discovery that could help make a meaningful difference in the recovery of sea stars and their ecosystems, she said. Gehman, too, said she wasn't sure the project would result in a singular answer. 'I thought it would be complicated. I thought there would be multiple things relying on other things,' she said. 'This was much clearer than I was expecting.' The discovery allows researchers to turn their efforts to deeper questions, including the possible role of warming ocean temperatures and the potential to breed sea stars in captivity to promote disease resistance and spur recovery, she said. The disease now appears to be seasonal, with outbreaks occurring in the warmer months, suggesting temperature may be a factor, said Gehman, adding she will soon conduct temperature experiments to investigate further. 'Does Vibrio pectenicida grow faster at warmer temperatures and the sea star can sort of survive at the growth rates at cooler temperatures, but when you get to warmer temperatures, they can't, is that what's happening?' The findings could help researchers understand where sea stars may struggle or survive with climate change in the future, Gehman said. Prentice said there are 'remnant' populations of sunflower stars along the B.C. coast, and its 'very possible' some could be more resistant to the wasting disease. She said finding and selectively breeding sea stars with a higher capacity to fight off the disease could produce 'superstar' sea stars for reintroduction in the wild. 'It seems like science fiction sometimes, but people are working on it,' she said. This report by Brenna Owen, The Canadian Press, was first published Aug. 4, 2025.
