What Is a Sea Cow 海牛是什么？

Sea cow is also called manatee.Manatees are aquatic1 mammals2 that belongto a group of animals called Sirenia3. In thisgroup there are also dugongs. Dugongs andmanatees are similar in size， colour andshape， but they’re different in their tails4.t u b ， l i a t d e d n u o r ， g i b a e v a h s e e t a n a Mdugongs have flat tails， like whales’tails.

海牛也叫manatee，是一种水生哺乳动物，属海牛目。海牛目的动物也包括儒艮。儒艮和海牛在大小、颜色和形状上都很相似，但它们的尾巴略有不同。海牛的尾巴大而圆，而儒艮则有着扁平的尾巴，就像鲸鱼尾巴一样。

Manateescanlivetotheageofabout50 or60 in thewild， butitispossibletheycouldlivelonger.Babymanateesstaywiththeirmotherforabouttwoyearsaftertheyareborn.

海牛在野外可以活到50 到60 岁左右，但也有可能活得更久。海牛宝宝出生后的前两年会和妈妈待在一起。

Unlike most mammals， manatees only have six bones in their neck. Usuallymammals have seven， like humans5. With this short neck， manatees could move itshead up and down， but not side to side. To look left and right， a manatee must turn itswhole body. Manatees are huge animals， much bigger than humans. A manatee growsinto 2.5 to 3.5 meters long and around 350 to 500 kilograms weight on average6.

与大多数哺乳动物不同，海牛的脖子只有六块骨头。通常，哺乳动物都有七块，比如人类。由于脖子很短，海牛只可以上下摆动头部，但不能左右移动。要左右看，海牛必须转动整个身体。海牛是一种巨大的动物，比人类大得多。成年海牛大约有2.5 到3.5 米长，平均体重约 350 到500 公斤。

What do manatees eat？

海牛吃什么？

Seagrasses and other plants underwater are most of a manatee’s food. Manateesspend about eight hours each day finding and digging plants. They eat up to 15% oftheir weight in food each day.

海草和其他水下植物是海牛的主要食物来源。它们每天花大约 8 个小时寻找和挖掘可以吃的植物，每天吃的食物重量高达体重的15%。

How long can manatees stay underwater？

海牛能在水下待多久？

Manatees are fully aquatic， whichmeans they don’t live on the land. But asmammals， they need air to breathe7.When awake， they usually come up to thesurface8 every two to four minutes， butthey can hold their breath for much longer.The longest record was 24 minutes by a West Indian manatee in Florida.

海牛是完全的水栖动物，这意味着它们不生活在陆地上。但作为哺乳动物，它们需要呼吸空气。醒着的时候，它们通常每隔两到四分钟就会浮出水面一次，但它们在水下屏住呼吸的时间可以更长。佛罗里达州的一只西印度海牛创下了24 分钟的最长纪录。

Adult manatees sleep underwater from 10 to 12 hours a day， but they come upfor air every 15 to 20 minutes. When a manatee sleeps， they need less air.

成年海牛每天在水下睡10 到 12 小时的觉，但每15 到20 分钟就会上来呼吸一次空气。海牛睡觉时，需要的空气更少。

How fast can a manatee swim？

海牛能游多快？

Manatees have a much slowerspeed than other mammals of theirsize. They are slow swimmers， butcan have a top speed of about 25kilometers per hour. However， theycan’t always swim in this speed.

海牛的速度比其他同等体型的哺乳动物慢得多。它们的游泳速度较慢，最高时速大约25 公里。然而，它们并不能一直以这种速度游动。

Are manatees in danger？

海牛是否濒临灭绝？

All manatees are in great danger or at a high risk9 of dying out. About140，000 manatees living in Amazon area were killed between 1935 and 1954 fortheir meat， fat and skin. People eat their meat， make their fat into oil， and use theirskin to make leather10. The manatee in Africa are also in danger， but people aretrying to save them. Manatee hunting is now illegal11 in some African countries.

所有海牛都处于极度危险或濒临灭绝的境地。1935 年至 1954 年间，生活在亚马逊地区的约14 万头海牛因其肉、脂肪和皮而被捕杀。人们吃海牛肉，用脂肪炼油，用海牛皮做皮革。非洲的海牛也濒临灭绝，但人们正在采取措施保护它们。在一些非洲国家，猎杀海牛现在是非法的。

Notes

1. aquatic 水生的；水栖

2. mammal 哺乳动物

3. sirenia 海牛目

4. tail 尾巴

5. human 人类

6. on average 平均来看

7. breathe 呼吸breath 呼吸；气息

8. surface 表面；水面

9. risk 危险；风险

10. leather 皮革

11. illegal 非法的