Latest news with #MontereyBayAquariumResearchInstitute
Al Jazeera
3 days ago
- Science
- Al Jazeera
Why have blue whales stopped singing? The mystery worrying scientists
Whale songs are far removed from the singing that humans are used to. Unlike our musical sounds, those produced by whales are a complex range of vocalisations that include groans, clicks and whistles and that can sound like anything from the mooing of a cow to the twitter of a bird. These vocalisations can be so powerful that they can be heard as far as 10km (6 miles) away, and can last for half an hour at a time. But while they may not be exactly dancing material, whale songs are critical for communication: between males and females during mating, or among a school of whales migrating. For researchers, these complex sounds are a window into whale behaviour, even if humans don't yet know exactly how to decode them. The frequency of songs and their intensity can signal various things: an abundance of food, for example. In recent studies, however, researchers have been alarmed to find that blue whales, the largest whales and, indeed, the largest mammals on Earth, have stopped singing at specific times. Their eerie quietness, scientists say, is a signal that ocean life is changing fundamentally. The most recent study, conducted by scientists from the Monterey Bay Aquarium Research Institute in California in the US and published in February, examined three types of whales. Researchers found that blue whales, in particular, have become more vulnerable to this change. What have researchers found, and where? At least two studies between 2016 and 2025 have found similar behaviour: blue whales have reduced their singing for stretches of time. The first study, conducted in the sea waters between the islands of New Zealand between 2016 and 2018, was led by scientists from the Marine Mammal Institute at Oregon State University in the US. Over that period of time, researchers tracked specific blue whale vocalisations linked to feeding (called D-calls) and mating (called patterned songs). Researchers used continuous recordings from underwater devices called hydrophones, which can log sounds over thousands of kilometres, and which were placed in the South Taranaki Bight – a known foraging spot for blue whales off the west coast of New Zealand. They discovered that during some periods, particularly in the warmer months of spring and summer when whales usually fatten up, the frequency and intensity of sounds related to feeding activity dropped – suggesting a reduction in food sources. That decline was followed by reduced occurrences of patterned songs, signalling a dip in reproductive activity. 'When there are fewer feeding opportunities, they put less effort into reproduction,' lead researcher Dawn Barlow told reporters. The results of that study were published in the journal Ecology and Evolution in 2023. Then, in a study published in the scientific journal PLOS One in February this year, researchers tracked baleen whale sounds in the California Current Ecosystem, the area in the North Pacific Ocean stretching from British Columbia to Baja California. Blue whales are a type of baleen whale, and the study focused on them, alongside their cousins, humpback whales and fin whales. Over six years starting in 2015, the scientists found distinct patterns. Over the first two years, 'times were tough for whales', lead researcher John Ryan, of the Monterey Bay Aquarium Research Institute in California, noted in a press statement, as the whales, particularly blue whales, were found to be singing less. Over the next three years, however, all three whale species were back to singing more frequently, the study noted. Why are blue whales singing less? Both studies found one main reason for the reduction of whale song: food or, in this case, the lack of it. It turns out that the research, conducted between 2015 and 2020, captured periods of extreme marine heatwave events that killed off krill, the small shrimp-like animals that blue whales feed on. Those heatwaves are part of a looming environmental catastrophe scientists have been warning about: ongoing global warming marked by increases in global average temperatures, and caused by high-emission human activities, chief among them being the burning of fossil fuels. Scientists say the world could soon reach a tipping point at which there will be irreversible change to the planet. Already, 2016, 2023 and 2024 have been recorded as the warmest years ever. Why are food sources disappearing for whales? Krill, which blue whales primarily feed on, are highly sensitive to heat and can all but vanish during heatwaves, the studies found. Their movement patterns also change drastically: instead of staying together, as they usually do, krill disperse when it is hot, making them harder for predators like blue whales to find. Typically, when foraging, blue whales sing to others to signal that they have found swarms of krill. If there is no food to sing about, it makes sense that there will be no singing. Heatwaves can also trigger harmful chemical changes in the oceans that encourage the growth of toxic algae, which causes poisoning and death to mammals in the oceans and sea birds, researchers have previously found, suggesting that blue whales are also at risk of being poisoned. In the more recent study in California, researchers found that in the first two years when whales were singing less frequently, there was also a reduction in other fish populations. Are blue whales more vulnerable than other whales? The second period of three years witnessed a resurgence of krill and the other fish, along with more whale singing. When krill again declined, blue whales again sang less frequently, while singing from humpback whales continued, the study noted. 'Compared to humpback whales, blue whales in the eastern North Pacific may be more vulnerable due to not only a smaller population size but also a less flexible foraging strategy,' Ryan, the lead author of the California study said in a statement. 'These findings can help scientists and resource managers predict how marine ecosystems and species will respond to climate change,' he added. It is likely, both studies say, that blue whales need to spend more time and energy finding food when it is scarce, instead of singing. Are other animals changing their sounds? Studies have found that climate change is altering the sounds of several other species as well. Nature-related sounds, such as birdsong from certain species, could disappear altogether in some places as warming temperatures alter animal behaviour. For example, some animals might move permanently away from their traditional habitats. In New York, scientists found that over a century (1900-1999), four frog species changed their calling patterns, which males use to attract females for mating, and which are usually tied to the warming of spring and early summer. Over time, some frogs were calling about two weeks earlier than usual, researchers found, adding that it signified summer was arriving earlier.
Yahoo
4 days ago
- Science
- Yahoo
Blue whales have gone silent. Why that has scientists worried about Earth's biggest animals ... and the ocean
Blue whales — the largest animals on Earth — aren't singing as much anymore, and that's got scientists concerned. A study published in PLOS analyzing six years' worth of acoustic data collected from the ocean's floor found that blue whale vocalizations have been decreasing as the animal's food sources have disappeared. The monitor — a hydrophone sitting on the sea floor off the coast of California — collected sounds from the various creatures in the ocean, including multiple whale species. By coincidence, the recordings began during a marine heatwave that is unprecedented in modern times. According to the study, the heatwave reduced the amount of krill available for blue whales to consume. As the krill disappeared, so too did the blue whale songs. Over the course of the acoustic collection, blue whale songs deceased by approximately 40 percent. 'When you really break it down, it's like trying to sing while you're starving,' John Ryan, a biological oceanographer at the Monterey Bay Aquarium Research Institute told National Geographic. 'They were spending all their time just trying to find food.' The marine heating event began in 2013, when a stubborn, dense pool of hot water — later dubbed "The Blob" — moved from the Bering Sea and the Gulf of Alaska down the eastern North American coast. In some places the ocean temperatures were more than 4.5 Fahrenheit above average due to the heating. The Blob grew and covered a 500 mile wide and 300 feet deep region in the Pacific Ocean. By 2016, it covered approximately 2,000 miles of the Pacific Ocean. The increase in temperature allowed for toxic algae blooms that killed off krill — tiny, shrimp like creatures — and other marine life. 'When we have these really hot years and marine heatwaves, it's more than just temperature,' Kelly Benoit-Bird, a Monterey Bay Aquarium marine biologist and co-author of the paper told National Geographic. 'The whole system changes, and we don't get the krill. So the animals that rely only on krill are kind of out of luck.' The blue whales were among those animals who were out of luck. They feed on densely packed krill — their huge mouths take in thousands of gallons of water at once, sucking in enormous numbers of the tiny creatures — but without krill present, they went hungry. Ryan said the whales have stopped singing because they're "spending all their energy searching" for food. "There's just not enough time left over—and that tells us those years are incredibly stressful," he said. Climate change, driven by the human burning of fossil fuels, will only make the situation worse, the researchers warn. The world's oceans already absorb more than 90 percent of the excess heat from climate change. 'There are whole ecosystem consequences of these marine heat waves,' continues Benoit-Bird. 'If they can't find food, and they can traverse the entire West Coast of North America, that is a really large-scale consequence.'
Metro
4 days ago
- Science
- Metro
The heartbreaking and worrying reason blue whales are going silent
To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video The ocean is going silent. Blue whales, the gentle leviathans that swim in all but one of the world's oceans, are the singers of the underwater world. Their groans, whistles and clicks are famously so soothing that they count as white noise, and they may even have a pho-ne-tic alphabet. These haunting melodies aren't just for fun – these giants do so to socialise, get around and differentiate friend from foe. But researchers have revealed that blue whales are singing less and less as they're simply too hungry to do so. Scientists have used underwater hydrophones – an aquatic version of microphones – to monitor and record their vocalisations off the coast of Monterey Bay, California. The Monterey Bay Aquarium Research Institute found that the beats are singing 40% less than they once did six years ago. Over this period, the temperatures in the ocean have been cranked up by major heat waves, causing toxic algae to bloom that kill krill and anchovies. Both are the main diet of blue whales, the study said. John Ryan, a biological oceanographer at the institute, told the National Geographic: 'When you really break it down, it's like trying to sing while you're starving. 'They were spending all their time just trying to find food.' Humpback whales have a more diverse diet of krill, plankton and schooling fish, so their song frequency didn't change amid the heatwave. Over the six-year study, a pool of warm water officially dubbed 'the blob' drifted into the Bering Sea and Gulf of Alaska. The blob warmed the ocean by 2.5°C, far more than El Niño, a natural climate pattern linked to warmer conditions in the Pacific Ocean, could. The 2,000-mile-wide blob caused a record-breaking outbreak of toxic algae so severe that it shut down crab fisheries, starved seabirds and killed plankton. As krill vanished from the seas, the blue whales scattered and had to spend all their energy searching for food rather than singing. The scientist said this suggests the mammals not only ate less but also mated less, given they vocalise low-frequency D calls when they do. The researchers said that the blue whales' acoustics are a warning for what's to come as climate change cranks the planet's thermostat up. Sea surface temperatures broke records last year, with a quarter of the oceans experiencing once-rare marine heat waves. These warmer oceans cause rising sea levels, bleaching coral reefs and more intense hurricanes. Sea basins absorb 90% of the excess heat trapped in the atmosphere from greenhouse gases, which are emitted by burning fossil fuels. More Trending Dr Judith Brown, projects director at Blue Marine Foundation, which supports governments to protect marine areas, described whale song as a 'truly eerily beautiful sound'. 'We know that 90% of global fish stocks are overfished – a harsh reality that threatens marine ecosystems,' she told Metro. 'Blue whales rely on krill to survive, and fishing krill, a species from the bottom of the food chain, occurs annually around Antarctica. This year, more than 620,000 tonnes of krill were taken in just a few months. 'High fishing pressure likely results in limited krill availability for whales. So it's no surprise that whales struggling to find sufficient food may no longer 'sing'.' Get in touch with our news team by emailing us at webnews@ For more stories like this, check our news page. MORE: Tarantulas with giant penises discovered and we're scared stiff MORE: Millionaire trophy hunter gored to death by 1.3 tonne bull on African safari MORE: Danish zoo asks owners to donate unwanted animals to feed to predators
Newsweek
4 days ago
- Science
- Newsweek
Blue Whales Go Silent Off California Coast, Sparks Alarm Among Scientists
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Researchers detected a drop in blue whale songs off the coast of California following a marine heat wave. A six-year study by the Monterey Bay Aquarium Research Institute (MBARI) showed songs detected were the lowest in 2015, following the climate event known as the "Blob." Detection of whale songs has since increased, but blue whale songs remain notably lower than humpback whale songs detected, which the researchers believe indicate the species may be more vulnerable to ocean condition changes. Newsweek has contacted the MBARI research team outside of regular working hours via email for comment. Why It Matters Whale songs provide key insight into ocean ecology and the health of whales, allowing scientists to make estimations on the prevalence of the species in certain areas, as well as how resilient different species are to ocean and habitat changes. As fewer blue whale songs are being detected by the institute's study, there is concern about how changing ocean conditions, likely caused by climate change, are impacting the species and what that will mean for biodiversity and whale numbers in the region. File photo: a blue whale raises its tail above the water surface off the coast of Long Beach, California. File photo: a blue whale raises its tail above the water surface off the coast of Long Beach, California. Nick Ut/AP What To Know In 2015, the "Blob" heat wave covered the West Coast, resulting in elevated temperatures ashore, while krill and forage fish, vital sources of food for whales, declined and harmful algal blooms began to spread. Fish species also moved northwards by hundreds of miles that year, showing a marked impact on how ocean temperatures affect migration patterns in sea life. The decline in krill was particularly problematic for blue whales, as krill is their only food source, while humpback whales also eat small fish such as anchovies and sardines so had other food sources during that year. The lack of food alongside the change in ocean conditions likely contributed to the drop in whale songs in 2015, as when krill and forage fish numbers increased in the third year of the study, whale songs started to increase as well, MBARI's research indicates. In the fifth year of the study, krill abundance was once again lower, as was the detection of blue whale songs, further emphasizing the link between krill availability and blue whale song detection. As humpback whales had other sources of food, as forage fish remained abundant that year, detection of their songs continued to significantly increase. Blue whales are forced to forage over a much larger geographic area when krill populations became depleted. While food availability was highlighted as a key factor in song detection, the researchers also note there are likely a number of other factors such as changes in local population abundance and the timing of their annual migration contributing to the changes in song detection. What People Are Saying John Ryan, a biological oceanographer who leads MBARI's Ocean Soundscape Team and was the lead author of this new study, said: "Analyzing baleen whale songs has revealed year-to-year variations that reflect changes in the availability of the species they forage on. These findings offer vital clues about how resilient different whale species may be in the face of changing ocean conditions." He added: "As the ocean changes, some species will be more affected than others. Compared to humpback whales, blue whales in the eastern North Pacific may be more vulnerable due to not only a smaller population size but also a less flexible foraging strategy. These findings can help scientists and resource managers predict how marine ecosystems and species will respond to climate change." What Happens Next The researchers have emphasized how listening to whale songs can reveal a significant amount of valuable information about different species, acting as a "window into their lives, their vulnerability, and their resilience," meaning the data will provide further insight into how continued changes to ocean conditions impact whales.
San Francisco Chronicle
5 days ago
- Science
- San Francisco Chronicle
Are blue whales going silent off the California coast? Here's what new data shows
A new study, led by researchers from the Monterey Bay Aquarium Research Institute, found that a 2015 marine heat wave, known as 'The Blob,' quieted the songs of humpback, blue and pin whales off the California coast. While humpback whale populations steadily recovered over subsequent years, blue whales — the biggest animals in the world — struggled amid changing ocean conditions. The authors uncovered that this change was due to foraging behavior. Such information is crucial for the restoration of whale populations, which have been decimated by human activity, said lead author John Ryan, a biological oceanographer at the Monterey Bay Aquarium Research Institute. 'We have to understand where and how they live,' Ryan said. 'And how our activities intersect with their lives.' The scientists carefully listened to the ocean environment, about half a mile below the surface, just outside the Monterey Bay. They used an underwater device known as a hydrophone: 'It's picking out all kinds of sounds, within and outside the range of human hearing,' Ryan said. The authors analyzed data collected from July 2015 to June 2021. They used machine learning to pick out humpback whale songs, which are complex and can span more than nine octaves, Ryan said. The scientists listened in on specific frequencies to pick out the songs of blue and pin whales. An analysis of the different species revealed distinct patterns over the six-year period. The percentage of days that humpback whale songs were detected steadily rose from year to year. By contrast, the share of days that blue whales songs were captured rose, then dipped following the third year of the study. The first year of the study marked a difficult time for whales. A marine heat wave depleted food resources, which meant harder hunting and scarcer prey. That year also coincided with 'the most severe toxic algal bloom we've ever seen on the planet,' Ryan explained. 'Poisoning of marine mammals by this toxic algal bloom occurred over the largest scale ever observed.' A harmful algal bloom sickened hundreds of sea lions and dolphins in Southern California this year. During the marine heat wave, krill and fish were in low abundance, forcing blue and humpback whales to spend more time foraging for food. This left less time for singing behavior. By the third year of the study, krill — small, shrimplike crustaceans that blue whales depend on for calories — were relatively abundant.. But by the fifth year of the study, krill abundance dropped, while fish were highly abundant, benefitting only humpback whales. 'Humpback whales would have an advantage because they are more flexible in their diet,' Ryan said. Based on chemical studies, the scientists suggest that blue whales traveled further to find food during this time, leaving less time for singing behavior. The authors investigated other potential reasons for the changes in whale song, such as population abundance, but changes in foraging conditions were the most consistent explanation. The study indicates that blue whales could be more vulnerable to changing ocean conditions than humpback whales. This could especially be a challenge in the future, as scientists project marine heat waves to become more frequent, longer, larger and more intense.
