These botos are huge - two and a half metres long. 这些亚马逊江豚体型巨大 身长达2.5米

180. more than in the whole of the Atlantic Ocean.
     这比整个大西洋的鱼类种数还要多
181. The Amazon is so large and rich in fish
     亚马逊河养育着丰富繁多的鱼类
182. that it can support fresh water dolphins.
     为淡水海豚提供了生存条件
183. These botos are huge - two and a half metres long.
     这些亚马逊江豚体型巨大 身长达2.5米
184. In these murky waters they rely on sonar to navigate and hunt.
     它们利用回声定位 在昏暗的水中探路和捕食
185. They work together to drive shoals of fish into the shallows.
     它们一起合作把鱼群赶到浅水区
186. Botos are highly social
     亚马逊江豚是高度社会型动物

来自《行星地球 第一季 第三集 Planet Earth S01E03 淡水》第 183 行