![]() The Convention on International Trade in Endangered Species of Wild Fauna and Flora lists the species as endangered and forbids any commercial trade of its products. Since 1966, blue whales have been protected globally by the International Whaling Commission. Climate change is also making oceans warmer and more acidic, which will likely lead to a further decline in krill. In some cases, krill may be heavily harvested by humans, which decreases the amountĪvailable to blue whales. Prey depletion is also a growing problem. Studies show that, because of ocean currents and fronts, ocean-borne plastics tend to concentrate in areas where whales feed. Water pollution can be from agricultural run-off, oil spills and plastics. When blue whales are exposed to noise pollution, such as seismic exploration and military sonar, they tend to stop feeding. Lawrence bearĭeep wounds and scars that are likely due to such events. ![]() For example, about 16 per cent of blue whales found in the Gulf of St. Ice entrapment, fishnet entanglement, ship strikes, noise and water pollution, prey depletion and disruption from whale watching activities. Other sources of blue whale injury and mortality include ThreatsNowadays, the only known natural predator to the blue whale is the killer whale, although it is generally a minor threat. Studied using satellite tags and acoustic detectors. Overall, the main contribution to population loss was in the Antarctic, where the largest group of blue whales previously lived. ![]() These hunts began in the North Atlantic but spread elsewhere once stocks dwindled. Then the invention of the exploding harpoon gun ushered in 110 years of blue whale catches. Whale was too fast and too strong to be caught. Still, today’s population is only about 3–11 per cent of what it was before large-scale hunting began. Though blue whales were hunted to near extinction in the 20th century, their populations are slowly increasing in most areas. Scientists have also recorded dives exceeding 30 minutes. They do not stay long at the surface and instead dive for 5–15 minutes at a time. However, the blue whale’s songsĪre generally infrasonic, meaning that they are made at such low frequencies that they are inaudible to the human ear.īlue whales are usually found alone or in small groups of two to four. For comparison, a rocket launch is about 180 decibels. Its songs, sung at up to 188 decibels, can be heard hundreds of kilometres away. In addition to being the world’s largest animal, the blue whale is one of the loudest. Its tongue against its upper jaw, straining the water out through baleen plates and eating what’s left behind. It then partly shuts its mouth and presses To do this, it lunges forward and takes large quantities of water and prey into its mouth. An adult whale can eat up to four tonnes a day. The blue whale’s favourite food is krill, a small shrimp-like crustacean. ![]() Blue whales usually mate with each other, but scientists have occasionally observed cross-breeding, notablyīlue whales do not stay long at the surface of the ocean, instead diving for between 5 and 15 minutes at a time. Six and eight months of age, calves drink up to 200 litres of their mother’s thick, 30–40 per cent fat milk each day, growing up to 100 kg daily. Calves are born after a 10–12-month gestation period and begin to grow quickly right away. From this age, females can give birth to single calves once every two or three years. Maturity around 10 years old, and males 12 years old. From this, scientists know that blue whales can live for 70–90 years - and possibly longer. Similar to how a tree’s age can be read from its growth rings, a blue whale’s age can be estimated from the waxy accumulation in its ears. ExpertsĮstimate that there are between 10,000 and 25,000 blue whales alive today, including between 1,000 and 3,000 in the North Atlantic Ocean and between 2,000 and 5,000 Some individuals migrate seasonally between higher and lower latitudes. Otherwise, they usually stay far offshore. When feeding, they can be seen in estuaries and shallow coastal areas. Blue whales are found in oceans almost anywhere on Earth.
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