Latest news with #MBARI
Newsweek
5 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.
National Geographic
09-06-2025
- Science
- National Geographic
Jellyfish are finally giving up their secrets
Gelatinous zooplankton, colloquially known as jellies, are an evolutionary hodge-podge of squishy, translucent creatures composed mostly of water. While this group does include 'true jellyfish' with their iconic rounded bell and stinging tentacles, it is also host to a smattering of creatures such as worms, primitive chordates, and snails with wings. A California sheephead (Semicossyphus pulcher) takes a bite out of a twin-tailed salp (Thetys vagina.) Jellies are poorly suited to life near shore, so when they find themselves in a kelp forest, they can make easy prey. 'If being 95 percent water is what unites the group, that is where it ends,' says Grace Cawley, a PhD candidate at Scripps Institution of Oceanography. Some are passive grazers, others track down their prey. Some are the size of a thimble, others can grow longer than a blue whale. Some cruise along the air-sea interface, others live thousands of meters beneath the surface. Cawley joked that the common reaction with jellies was ''oh, it's gooey?' Throw it with the gelatinous zooplankton.' In failing to recognize their diversity, humankind has overlooked some of the most ancient creatures on our planet. But thanks to advances in technology, scientists are now racing to decipher how jellies will shape the future of Earth's oceans. The hard part about squishy bodies The study of gelatinous zooplankton began in the late 1800s by scooping specimens out of the water from docks and ships. 'A lot of [early inquiry] was really just, 'what is this thing'?' says Steven Haddock, a leader in zooplankton biology at Monterey Bay Aquarium Research Institute (MBARI). Typical methods for investigating evolutionary history simply didn't work. Jellies lack the bones and shells that make for good fossils—scientists struggled to keep them alive in the lab long enough to observe their life cycles—and attempts to preserve them resulted in jars of cloudy film that bore no resemblance to the original creature. The proliferation of larger, faster research vessels around the mid-1900s meant that it became possible to sample new and remote regions of the ocean. Scientists rushed to ask ''how many?' and 'how much?' before having answered 'who?' and 'how?'' wrote Haddock in an early paper . This 1 inch lemon jelly (Aegina citrea) may not seem intimidating, but it is a predator. Its prey are other gelatinous zooplankton like salps and ctenophores. Hula-skirt siphonophores (Physophora hydrostatica) normally live deeper than 700 meters, but strong currents will occasionally carry them to the surface. Many different groups have made the transition to life in the water column. This pelagic snail has evolved to be transparent, but it still retains its shell. These animals blur the line of what is considered a gelatinous zooplankton. In their case, it largely comes down to the context in which they are being studied. Many species of salp (colonial tunicates) have a complex life cycle that alternates between sexual and asexual reproduction. Once the individuals in the colony mature, they will break off to begin reproducing sexually. When Scripps Institution ecologist Elizabeth Hetherington began studying gelatinous zooplankton, she was shocked by how little was known about their lives. 'There were so many questions that seemed pretty simple, like basic questions about distribution and abundance … that I couldn't find answers to.' Since the early 2000s, advances in technology have revealed that they play a more vital role in the ocean's food web than scientists thought. One paper from 2022 suggested that pelagic tunicates—gelatinous sea creatures that float in the open ocean—could be responsible for transporting more than 10 percent of carbon that is eventually stored in the ocean floor. The discovery that this single group of jellies could play such an influential role in the carbon cycle surprised scientists. The significance of all the ocean's jellies combined is unclear; however, the role they play in helping store carbon is probably underestimated. New technology that allowed scientists to study tiny bits of DNA also yielded new insights into jellies themselves. One study published in 2023 found that ctenophores, the most fragile of the gelatinous zooplankton, may be the oldest animal species living on Earth. Not only did these new methods revolutionize the study of individual species, but they also transformed our understanding of the open ocean. Jellies were more prevalent than previously thought and enthusiastic participants in the food web , hunting and being hunted. Using DNA metabarcoding, a technique used to identify multiple species within a mixed sample, 'we [could] detect gelatinous zooplankton in the guts of predators' explains Hetherington. Though the remnants of jellies were rarely visible, their DNA has been found in stomach contents of a wide variety of birds, fish, and sea turtles, disproving the idea that they were just dead-ends in the food chain. As larvae, many fish species mimic the traits of gelatinous zooplankton to decrease their chances of being eaten. This larval cusk eel is nearly transparent which helps it hide in the open ocean. Scientists are still trying to answer major questions about how many species exist, in what numbers, and how those populations might be changing. 'In an oceanographic context, we're still a long way from having the big picture biogeochemistry stuff figured out' remarks Haddock. 'Questions like 'Are jellyfish increasing?', 'How much jellyfish biomass is there relative to fish biomass?', 'What is the true diversity of jellies?' … we're still struggling to answer those.' To answer these questions about jelly species, scientists must also learn more about how they fit in their ocean habitats. 'The ocean is not a stagnant place where nothing happens, the ocean is this dynamic, complicated system,' says Cawley. Jellies are no exception. Instead of maintaining a consistent, predictable population, many gelatinous zooplankton follow extreme boom and bust cycles that scientists are still trying to understand. One species of pelagic tunicate called a pyrosome can bloom with such intensity that it will make up 80 percent of the biomass in a given area. When blooms like this occur, they affect every aspect of an ecosystem from the food web to the chemistry of the water. With warming temperatures, overfishing, and pollution rapidly changing our oceans, answering these questions is becoming even more difficult. 'All of these ecosystems are impacted by warming and by pollution so it's important to get the baseline of where we are now,' but in a system as fluid as the ocean, a baseline is more complicated than a set of measurements, clarifies Hetherington. 'We should shift our thinking from baseline to baselines, that it's not this one thing, it's this dynamic range.' A baseline needs to capture the underlying patterns of our oceans. It's an intimidating challenge that begins with demystifying where these jellies are living and what they are doing. Still, in Haddock's eyes, it's an exciting time to study gelatinous zooplankton. 'There are new species within a stone's throw of New York City or Tokyo … if you just look in the right ways'
National Geographic
27-02-2025
- Science
- National Geographic
Behold the pigbutt worm, mystery of the deep
More than 90 percent of the creatures living in the ocean have yet to be described, so it's not all that surprising that scientists continue to find new species of fish, crustaceans, jellies, and sea slugs each time they venture into the ocean's deepest, darkest haunts. But sometimes they encounter a creature so strange, it defies quick categorization. Such was the case in 2001 when experts from the Monterey Bay Aquarium Research Institute piloted a remotely operated submersible to depths between 2,700 and 7,200 feet off the coast of California. It was there, in the lightless Midnight Zone, named for fact that no surface light reaches these depths, where they came face to face with a translucent, pink blob about the size of a hazelnut. 'It was bigger than most of the small particles that we see down there,' says Bruce Robison, a senior scientist at the MBARI. 'As we zoomed in on it with the camera, everybody was remarking, 'I've never seen anything like that before.''
