[ti:Study: Blue Whales Swallow 10 Million Microplastic Pieces a Day] [by:www.51voa.com] [00:00.00]更多听力请访问51VOA.COM [00:00.04]Researchers have estimated that blue whales take in [00:04.96]about 10 million pieces of microplastics each day. [00:10.64]Microplastics are particles of plastic debris [00:15.84]that are less than 5 millimeters long. [00:19.48]They come from the breakdown of many kinds of [00:23.48]plastic products and industrial waste. [00:28.20]Particle levels have been building up [00:31.16]in the world's oceans for many years. [00:34.52]The possible health effects on whales [00:38.00]from eating microplastics [00:40.16]are still not well understood. [00:43.84]Scientists studied three species of baleen whales [00:49.48]– blue, fin and humpback. [00:52.68]Baleen whales are born without teeth. [00:56.52]But they have special plates in their mouths that filter food. [01:02.00]They feed on very small animals, [01:05.20]mainly the shrimp-like creatures called krill. [01:09.48]A study by the researchers says the estimated [01:14.40]10 million pieces of microplastics [01:18.04]blue whales eat daily weigh about 44 kilograms. [01:24.28]The whales were studied off America's Pacific coast. [01:29.44]Research results were recently reported [01:33.20]in the publication Nature Communications. [01:37.28]The study found that fin whales may take in [01:41.84]up to 6 million microplastic pieces a day. [01:46.20]Humpbacks that mostly feed on krill likely eat about [01:51.56]4 million microplastic pieces daily, the researchers said. [01:57.24]Humpbacks that favor fish may take in a much smaller amount, [02:03.32]about 200,000 pieces a day. [02:07.20]Matthew Savoca was a co-writer of the study. [02:12.48]He told the Reuters news agency [02:15.56]that about 99 percent of the plastic material [02:20.40]came from other animals the whales eat [02:24.08]-- not from the water they filter. [02:27.24]The study demonstrates the different reasons [02:31.48]baleen whales may be at a heightened risk [02:35.32]for taking in microplastics. [02:38.40]These include the way they feed, the amount of food they eat [02:43.80]and the fact that their environment is close to polluted areas. [02:49.44]Blue whales can grow up to 30 meters long. [02:54.40]Fin whales can reach 24 meters, [02:57.92]while humpbacks are generally about 15 meters. [03:03.00]The researchers estimated the daily microplastic intake [03:08.88]by examining the food search behavior of 126 blue whales, [03:15.84]65 humpbacks and 29 fins. [03:21.04]They used measurements from electronic tag devices [03:26.28]that they attached to the animals' backs. [03:29.68]The device was equipped with a camera, [03:33.12]microphone and a GPS tracker. [03:37.24]They then considered levels of microplastics [03:41.16]that exist in the travel path of the whales. [03:45.48]A study published last year suggested [03:49.92]that blue whales off the U.S. Pacific coast [03:53.88]eat about 10 to 20 tons of krill daily. [03:58.60]Fin whales eat an estimated 6 to 12 tons of krill a day, [04:04.36]while humpbacks take in about 5 to 10 tons of krill [04:10.00]or 2 to 3 tons of fish daily. [04:13.96]The new study found that the whales mainly feed [04:18.44]at ocean depths of 50 to 250 meters. [04:24.00]This is within the area with the highest measured [04:28.48]microplastic levels in the open-ocean environment. [04:33.92]I'm Bryan Lynn. 更多听力请访问51VOA.COM