Scientists Find Whales Eat ... A Lot!
2021-11-11
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1The blue whale is the largest animal to ever live on our planet.
2You might wonder how much such a large creature eats. Well, you are not alone.
3Scientists recently carried out a study to find out how much blue whales - and some of their closest relatives - eat in a day.
4Their findings were not surprising.
5They found the whales eat a lot.
6In just one day, blue whales living in the North Pacific Ocean can eat about 14.5 metric tons of krill.
7Krill are crustaceans and look like very small shrimp.
8That means blue whales eat around 1450 metric tons of food every year.
9Matthew Savoca of Stanford University was the lead writer of the study, which appeared recently in the publication Nature.
10When speaking of the findings, Savoca said, "It's an unimaginable amount of food."
11Nick Pyenson was the co-writer of the study.
12He said the amount of food blue whales eat in a day is about the weight of "one fully-loaded school bus."
13Pyenson works at the Smithsonian Institution's National Museum of Natural History in Washington, D.C.
14He is an expert in the study of extinct marine mammals.
15Savoca also described the blue whale's size as "unimaginable."
16Blue whales are larger than even the biggest dinosaurs.
17They can grow to 33 meters long and weigh about 181 metric tons.
18The animal can grow to about the size of a Boeing 737 airplane.
19For the study, the researchers followed 321 whales living in the Atlantic, Pacific and Southern oceans.
20Some were blue whales.
21The rest were six other baleen whale species: humpback, fin, bowhead, right, Antarctic minke and Bryde's whales.
22These huge ocean mammals were found to eat up to three times more food than scientists had thought.
23To measure the amount of food the whales ate and to study eating behaviors, the researchers used many devices.
24Electronic tag devices were attached to the animal's back.
25They also used cameras, microphones, a GPS locator device and an instrument that follows movement.
26They used drones to estimate the size of a whale's mouth area and how much food it could eat at one time.
27And they used instruments that recorded sound waves to estimate the amount of food in the waters near the whales.
28Baleen whales eat small creatures that include krill, fish or crustaceans called copepods.
29The largest whale species prefer krill.
30Smaller species such as humpback, Bryde's or minke whales can eat fish or krill.
31Most baleen whales do not eat year-round.
32They eat about 100 days out of the year, mostly during the summer mating season.
33They eat very little the rest of the year.
34There was another important part of the study: Knowing how much waste the whales excrete.
35Because they eat so much, they also produce much more excrement, or waste material, than scientists had thought.
36This waste material provides important nutrients for ocean ecosystems.
37By eating so much and then producing waste material, baleen whales help nutrients stay on the sea surface.
38These nutrients help to form phytoplankton -- extremely small organisms that take in carbon.
39Phytoplankton serve as the base of ocean food webs.
40Whale hunting during the 20th century caused sharp drops in whale populations.
41Pyenson said that before whale numbers dropped from hunting, the animals were able to support "far more productive ocean ecosystems."
42He added that supporting whale recovery may help repair "ecosystem functions lost in the past hundred years."
43I'm Anna Matteo.
1The blue whale is the largest animal to ever live on our planet. You might wonder how much such a large creature eats. Well, you are not alone. 2Scientists recently carried out a study to find out how much blue whales - and some of their closest relatives - eat in a day. 3Their findings were not surprising. They found the whales eat a lot. 4In just one day, blue whales living in the North Pacific Ocean can eat about 14.5 metric tons of krill. Krill are crustaceans and look like very small shrimp. That means blue whales eat around 1450 metric tons of food every year. 5Matthew Savoca of Stanford University was the lead writer of the study, which appeared recently in the publication Nature. When speaking of the findings, Savoca said, "It's an unimaginable amount of food." 6Nick Pyenson was the co-writer of the study. He said the amount of food blue whales eat in a day is about the weight of "one fully-loaded school bus." 7Pyenson works at the Smithsonian Institution's National Museum of Natural History in Washington, D.C. He is an expert in the study of extinct marine mammals. 8Savoca also described the blue whale's size as "unimaginable." Blue whales are larger than even the biggest dinosaurs. They can grow to 33 meters long and weigh about 181 metric tons. The animal can grow to about the size of a Boeing 737 airplane. 9For the study, the researchers followed 321 whales living in the Atlantic, Pacific and Southern oceans. Some were blue whales. The rest were six other baleen whale species: humpback, fin, bowhead, right, Antarctic minke and Bryde's whales. These huge ocean mammals were found to eat up to three times more food than scientists had thought. 10To measure the amount of food the whales ate and to study eating behaviors, the researchers used many devices. Electronic tag devices were attached to the animal's back. They also used cameras, microphones, a GPS locator device and an instrument that follows movement. They used drones to estimate the size of a whale's mouth area and how much food it could eat at one time. And they used instruments that recorded sound waves to estimate the amount of food in the waters near the whales. 11Baleen whales eat small creatures that include krill, fish or crustaceans called copepods. The largest whale species prefer krill. Smaller species such as humpback, Bryde's or minke whales can eat fish or krill. 12Most baleen whales do not eat year-round. They eat about 100 days out of the year, mostly during the summer mating season. They eat very little the rest of the year. 13There was another important part of the study: Knowing how much waste the whales excrete. 14Because they eat so much, they also produce much more excrement, or waste material, than scientists had thought. 15This waste material provides important nutrients for ocean ecosystems. 16By eating so much and then producing waste material, baleen whales help nutrients stay on the sea surface. These nutrients help to form phytoplankton -- extremely small organisms that take in carbon. Phytoplankton serve as the base of ocean food webs. 17Whale hunting during the 20th century caused sharp drops in whale populations. Pyenson said that before whale numbers dropped from hunting, the animals were able to support "far more productive ocean ecosystems." 18He added that supporting whale recovery may help repair "ecosystem functions lost in the past hundred years." 19I'm Anna Matteo. 20Will Dunham reported this story for Reuters news agency. Anna Matteo adapted it for VOA Learning English. Ashley Thompson was the editor. 21_________________________________________________________ 22Words in This Story 23crustacean - n. a type of animal (such as a crab or lobster) that has several pairs of legs and a body made up of sections that are covered in a hard outer shell 24marine - adj. of or relating to the sea 25mammal - n. a type of animal that feeds milk to its young and that usually has hair or fur covering most of its skin 26baleen - n. a tough material that hangs down from the upper jaw of whales without teeth and is used by the whale to filter small ocean animals out of seawater 27species - n. a group of similar living things that ranks below the genus in scientific classification and is made up of individuals able to produce offspring with one another 28locator - n. one that finds something (such as a mining claim or the course of a road) 29prefer - v. to like (someone or something) better than someone or something else 30excrete - v. to pass (waste matter) from the body or from an organ in the body 31ecosystem - n. the whole group of living and nonliving things that make up an environment and affect each other 32function - n. the action for which a person or thing is designed or used