Foreign media: Baleen reflects global climate change

2022-05-25 0 By

According to Buenos Aires Business News on March 25, scientific research shows that baleen can serve as an important marker of climate change.The mane-like structures that toothless whales, such as humpbacks and southern right whales, use to feed hold a chemical record of their feeding patterns, the report said.Scientists from the University of New South Wales in Australia have uncovered the secret hidden in the jaws of both species and revealed how these large Marine mammals adapt to environmental changes over time by studying their baleen.The researchers demonstrated that these changes in whale feeding habits, which date back nearly 60 years, are linked to changes in climate cycles.”It’s amazing that you can reveal all this information about feeding patterns and environments just by analyzing baleen plates in their mouths,” said Adelaide Durden, a PhD student in the DEPARTMENT of Science at the University of New South Wales and lead author of the study.In the study, published in the US journal Frontiers in Marine Science, researchers compared environmental data with information obtained from baleen of humpback and southern right whales in the Pacific and Indian Oceans to see if their behaviour reflected climate change over time.They found that weather events like La Nina, which bring devastating floods, are also bad for humpback whales because they force them to migrate up the east coast of Australia, said Tracey Rogers, a Marine ecologist and professor at the University of New South Wales and the study’s other lead author.Through analysis of baleen samples from museums and data published in previous studies, they found migrating humpbacks show signs of poor feeding during the duration of La Nina.La Nina is a massive weather cycle that affects the availability of food in the oceans.Changes in the environment make baleen whales vulnerable because they are large and require a lot of food.”The situation is also complicated by their survival strategies,” Rogers said.When they leave well-fed feeding grounds to breed, they fast for long periods of time.That’s why they’re extremely vulnerable to changes in the ocean-atmosphere cycle, because those changes can affect the availability of food.”The difficulties involved in studying such large animals can complicate laboratory work, so researchers have focused on smaller tissues that keep more detailed records of the animals’ movements.For filter-feeding whales, the long, thin baleen plates that dangle from their upper jaws allow them to capture large numbers of small prey at once, but they also store chemical clues called stable isotopes that provide clues to their feeding habits.”As baleen grows, biochemical signals from food are picked up.Like information on a page, they don’t change over time.”Rogers explains.These clues allowed researchers to reconstruct the whales’ behavior over time: what they ate and the general area they were in at the time.The researchers found that changes in stable isotopes in the baleen of humpbacks matched changes in climate cycles.This means that as climate forces changes in resource availability, the feeding patterns of these whales will also change.”The pattern of stable isotopes in baleen reflects physiological changes in whales, but we also found a link between these isotopes and changes in the environment at the time,” Durden said.Humpback whales breed in warm tropical waters during the winter and return to Antarctic waters in the summer to feed.As they move into the tropics, they are removed from adequate food sources and must rely on their own reserves and resources provided by Australian waters to survive.”They’re filter-feeders,” Durden said. “They feed on a lot of krill, and they use a lot of energy to feed.”Disclaimer: This article is reproduced for the purpose of conveying more information.If the source is wrong or violated your legitimate rights and interests, please contact the author with proof of ownership, we will promptly correct, delete, thank you.Email address: newmedia@xxcb.cn