Invasive bullfrogs ‘eat everything' — including turtles — at Yosemite, study says
When University of California, Davis, researchers first began studying four ponds at the park, they were overwhelmed by non-native American bullfrogs, a news release said.
'At night, you could look out over the pond and see a constellation of eyes blinking back at you,' said Sidney Woodruff, a UC Davis Ph.D. candidate and lead author of the study. 'Their honking noise is iconic, and it drowns out native species' calls.'
The invasive frogs had decimated the native population of northwestern pond turtles, according to the study, published in the May issue of the journal Biological Conservation.
Together with the southwestern pond turtle, northwestern pond turtles are the only native freshwater turtles in California, the university said.
Northwestern pond turtles have vanished from over half their range, which stretches from Baja California to Washington state.
At Yosemite, the only surviving turtles in the ponds surveyed were the ones that were too big for bullfrogs to eat, the study found.
American bullfrogs are native to the eastern United States but don't belong in the West.
'One reason American bullfrogs are among the top worst globally introduced pests is because they eat everything — anything that fits into their mouth,' said senior author Brian Todd, a UC Davis professor in the Department of Wildlife, Fish and Conservation Biology. 'They've been causing declines to native species everywhere they're introduced, which is around the world.'
The bullfrogs were introduced to Yosemite National Park in the 1950s and quickly spread throughout the park, researchers said.
While their arrival was believed to be linked to the decline in pond turtles, it wasn't confirmed until the study took place, according to researchers.
Between 2016 and 2022, researchers monitored four ponds at Yosemite, two with bullfrogs and two without, the study said.
Turtles were 2 to 100 times more prevalent at the ponds where bullfrogs were absent, researchers said.
When bullfrogs were removed from the other two ponds in 2019, researchers found juvenile pond turtles in them for the first time, the study said.
'As bullfrog presence declined, we started to hear other native frogs call and see native salamanders walking around,' Woodruff said. 'It's nice to be able to go back to these sites and hear a chorus of native frogs calling again that previously would not have been heard.'
The Western Pond Turtle Range-wide Conservation Coalition, Yosemite Conservancy, U.S. Geological Survey and USDA National Institute of Food and Agriculture funded the study.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Boston Globe
14 minutes ago
- Boston Globe
The White House is launching a review of exhibits at eight Smithsonian museums. Here's what to know.
In response, the Smithsonian said in a statement on Tuesday that it remained committed to 'scholarly excellence, rigorous research, and the accurate, factual presentation of history.' Get Starting Point A guide through the most important stories of the morning, delivered Monday through Friday. Enter Email Sign Up 'We are reviewing the letter with this commitment in mind and will continue to collaborate constructively with the White House, Congress, and our governing Board of Regents,' it said in a statement. Advertisement Here's what to know about the Smithsonian and the Trump administration's review of its museums. What is the Smithsonian Institution? A Smithsonian Institution sign is seen on the National Air and Space Museum on the National Mall on March 28, 2025 in Washington, D.C. Kevin Dietsch/Getty The Smithsonian Institution is the world's largest museum, education, and research complex, and includes 21 museums and the National Zoo, with 11 museums lining Washington's National Mall. It was founded with funds from British scientist James Smithson, who left his estate to the United States to create 'an establishment for the increase and diffusion of knowledge' in Washington. Which Smithsonian museums are under review? The review, first Advertisement 'This initiative aims to ensure alignment with the President's directive to celebrate American exceptionalism, remove divisive or partisan narratives, and restore confidence in our shared cultural institutions,' the letter said. The letter said additional museums would be reviewed in subsequent phases. How long will the review take and what will it entail? The review will take a look at all public-facing content, such as education materials, social media and digital content 'to assess tone, historical framing, and alignment with American ideals,' according to the letter. The review will also include curatorial processes and guidelines, exhibition planning and collection use. The White House is directing the museums to submit materials from exhibits and drafts for upcoming events within 30 days. Within 75 days, museums are asked to submit the 'remaining requested documentation including promotional literature, grant data, educational materials, and guided tour content.' Within 120 days, the letter said, museums will be expected to take corrective action, 'replacing divisive or ideologically driven language with unifying, historically accurate, and constructive descriptions.' Earlier this month, its National Museum of American History had temporarily What's Trump's existing relationship with the Smithsonian? On March 27, Trump Advertisement The order placed Vice President JD Vance, a member of the Smithsonian Institution's Board of Regents, in charge of overseeing the effort to 'remove improper ideology' across the institution's museums, education and research centers, and the National Zoo. 'Museums in our Nation's capital should be places where individuals go to learn — not to be subjected to ideological indoctrination or divisive narratives that distort our shared history,' the Material from the Associated Press was used in this report. Alyssa Vega can be reached at
Time Magazine
an hour ago
- Time Magazine
Should You Take a Vitamin B12 Supplement?
Everyone needs vitamin B12: It helps the body produce red blood cells and maintain healthy brain function, along with so many other things. But are you getting enough of it? Here's what to know about vitamin B12 and whether you should consider upping your levels. A boon for brain health 'Vitamin B12 is important for brain health because it helps protect nerve cells in the brain, which support memory and thinking skills,' says Michelle Routhenstein, a preventive cardiology dietitian and certified diabetes educator in New York. It's water-soluble, so the body does not store it in large amounts, and daily intake is essential. The current federal recommendations are for adults to get 2.4 mcg of vitamin B12 per day. Great food sources of B12 include seafood like oysters, salmon and tuna, beef, and fortified products like nutritional yeast, plant-based milks, some breads and breakfast cereals, says Routhenstein. But some recent research suggests that some people may need even more than that. Vitamin B12 deficiencies can impact your brain function even when your intake levels are considered normal, says Dr. Ari J. Green, a professor at the University of California, San Francisco's department of ophthalmology. In a recent study, Green and his colleagues found that people with B12 levels that were technically normal but on the lower end of the range had impaired brain function. 'We could detect neurological impairment at levels currently considered 'normal,' independently of other factors like years of education," particularly in older people, says Dr. Alexandra Beaudry-Richard, a resident at McGill University and co-author of the study. 'To us, this should reinvigorate a conversation about how much B12 is needed for optimal neurological function.' Read More: Should You Take a Vitamin D Supplement? Other studies have found that people with Alzheimer's disease and mild cognitive impairment tend to have lower B12 levels—and supplementation with B12 can reduce the rate of brain atrophy. However, on the opposite end, the study showed signs of a possible detrimental effect on the brain when people had high B12 levels in their blood. 'This warrants further studies to evaluate what healthy B12 levels are on both ends of the spectrum,' says Dr. Ahmed Abdelhak, one of the study's authors and a clinical instructor in neurology at UCSF School of Medicine. Should you take a B12 supplement? You can (and should) get B12 from your diet, but some people may have a tough time getting adequate levels of the nutrient from food alone. Older adults are more likely to develop vitamin B12 deficiencies because the vitamin requires stomach acid to be absorbed, and stomach acid production starts to decline with age. Routhenstein recommends people look closer into their B12 status starting around age 50 or if they are at higher risk of a B12 deficiency. This category includes vegans and vegetarians, people taking specific medications that interfere with B12 absorption such as metformin or proton pump inhibitors, and those who have gastrointestinal disorders like Crohn's, celiac, or atrophic gastritis. You can get tested for a vitamin B12 deficiency at your annual physical. If you are deficient, your doctor might recommend supplementation. Read More: 7 Surprising Symptoms of Lyme Disease The UCSF study authors recommend checking levels starting at age 70, but you can get it checked on a standard blood test at any age through your primary care physician. Dr. Ralph Green, a professor of pathology and lab medicine at the University of California, Davis—and another author on that recent study—says that checking B12 may also be valuable for people who have unexplained symptoms that have been linked to B12 deficiency. For those with declining gastric function, he says taking supplements is likely the best way to promote absorption, and the level of supplementation a person should consume depends on whether their absorption is normal or not. Pregnant women, too, need higher B12 intake to support fetal brain development; if you're pregnant, consult with your ob-gyn about optimal B12 levels for you. What kind of B12 supplement is best? B12 in supplements and fortified foods can be more easily absorbed than from food, especially for older adults and those with absorption issues, says Routhenstein. If your doctor has advised you to take a B12 supplement, it's best to ask them to recommend specific dosages and brands. But Routhenstein recommends following these general guidelines when selecting a B12 supplement. Of course, no supplement is a cure-all, and there are other ways to support brain health, including maintaining a healthy diet and exercise regimen. Activities that stimulate multiple brain areas simultaneously are excellent at promoting cognitive longevity, Beaudry-Richard says. Practicing a musical instrument, dancing, and studying a foreign language daily, for example, all recruit 'brain circuits responsible for vision, hearing, movement, emotions' and more. 'It's like a full-body workout for the brain,' she says.
Yahoo
2 hours ago
- Yahoo
Scientists discover surprising cause of dangerous dust problem impacting US region: 'A dominant contributor'
Scientists discover surprising cause of dangerous dust problem impacting US region: 'A dominant contributor' Farmland left idle and dormant is creating an unhealthy dust problem in California. Over 1 million acres of fallow farmland are contributing to the growing dust, which has health and climate implications in the state's Central Valley. What's happening? According to the University of California, Merced, approximately 77% of fallowed land in California is connected to 88% of the human-caused dust events. UC Merced professors studied this phenomenon and published their findings in the journal Communications Earth & Environment. The issue is especially prevalent in Fresno, Kern, and King counties, where corn, wheat, and cotton fields are routinely fallowed. Here, unplanted farm fields are susceptible to wind erosion, resulting in dust that is often contaminated with chemicals and pathogens. This effect is linked to human respiratory diseases and even death. Certain fungal diseases spread through dust and disproportionately affect vulnerable populations. The particulate matter may contribute to everything from cardiovascular issues to dementia, as well as traffic fatalities due to reduced visibility on roads. California's Central Valley is a significant source of dust, as it is a major agricultural production region in the U.S. Researchers are studying the impacts of dust on local snowmelt and water resources. "Because our study points to fallowed or idled farmlands as a dominant contributor, that may change how we estimate overall dust impact," said one of the researchers, Adeyemi Adebiyi. Do you worry about air pollution in your town? All the time Often Only sometimes Never Click your choice to see results and speak your mind. Why is farmland dust significant? Unfarmed lands have been expanding in recent years due to limited water resources and economic decisions. The Sustainable Groundwater Management Act has also limited the amount of water that farmers can use annually. When these lands remain exposed and uncultivated, they produce more dust, which impacts the environment and surrounding communities. Increased dust activity is affecting the health of people and natural ecosystems. More dust in our atmosphere creates ripple effects and hinders plant growth. Overmining, overgrazing, and extended agricultural breaks are creating conditions where degrading land is fueling our changing climate and threatening the global food supply. What's being done to control harmful dust? In the study, the UC Merced researchers recommended that farmers plant cover crops and ground cover plants to reduce dust and improve soil health. They also suggested land transitions to use fallowed farmlands for habitats and renewable energy. To mitigate public health risks and regional climate change associated with precipitation and snowmelt, agricultural practices in the Central Valley must shift. Fortunately, there are many natural solutions to address air pollution issues, like the increase in dust. Some communities have explored organic and water-based dust suppressants containing biodegradable surfactants to address dust issues. Preventing the spread of dust may also involve reducing vehicle exhaust fumes, maintaining proactive air quality monitoring, and promoting sustainable land use. Increasing dust is one of the many critical climate issues affecting California's Central Valley and other agricultural regions worldwide. By raising awareness of the issue and volunteering your time and efforts, you can take local action in your community to address dust pollution and preserve more breathable air for everyone. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet. Solve the daily Crossword
