字幕表 動画を再生する 英語字幕をプリント Dolphins are extremely intelligent mammals which are part of the family that include pilot whales and Orcas. The are found around the world and in shallow waters around the continental shelves. Dolphins are carnivores that mainly eat squid and crustaceans. They are generally grey in colour with darker backs and lighter undersides. They use echolocation to help them hunt and navigate the oceans. They listen for echoes and their senses help to guide them around. They are very agile creatures and are known for their playful behaviour. In order to view their surroundings, they will spy-hop which is where they will rise up vertically out of the water. It is thought that dolphins look to conserve their energy by swimming alongside ships, a practice known as bow riding. They are social animals and will live in groups together often synchronising their movements with one another. By being in groups, they can hunt more effectively and protect one another. In order that they can sleep half of a dolphins brain is asleep whilst the other half stays awake so they can continue to breathe and stop from drowning. Dolphins tend to mate throughout the year but there are seasonal peaks in spring and fall. Depending on the species, they will have a gestation period of between 9 and 17 months and by the time they are ready to give birth, they will distance themselves from the rest of the pod and travel towards the surface and give birth. Dolphins will usually give birth to one calf a year. Twins have been evidenced but are rare in the Dolphin world as soon as a calf is born it will be taken to the surface so it can breathe. The Dolphin will nurse the calf for between 11 months to 2 years. Once it has been nursed it will stay with its mother for anything between 3 and 8 years old.
B1 中級 米 イルカの事実。イルカについての14の事実 (Dolphin Facts: 14 facts about Dolphins) 358 10 南一 に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語