The manatee is one of the most endangered animals. Today， with only a few thousand left in the world， these special ocean animals could easily die out.

Looking something like a cross between a dolphin and a hippo manatees have been described as “giant grey sweet potatoes ”. They are commonly known as sea cows because of their size and plant?based diet. Manatees live on sea grass， much like cows live on grass in fields. An adult manatee eats about 70 kg of sea grass every day. Growing up to 3m long and weighing 1，000 kg or more， these gentle giants of the ocean are harmless. In fact， they are known to be friendly.

Manatees live in the shallow（淺的）coastal seas and rivers. They are long?lived animals， reaching ages of more than fifty years. However， they give birth to only one baby every two to five years.

Weather change is one of the dangers to manatees. It has led to fast growing of some poisonous （有毒的）water plants that can kill manatees and the sea grass that they eat. Some manatees also die of diseases.

However， most manatees die because of people’s activities. Humans not only destroy the manatees’ homes， they also kill or hurt them as a result of their carelessness. Being slow swimmers near coasts， manatees are always in danger of being hit by fast?moving boats. Sometimes they also eat fishing hooks （魚鉤） or rubbish， or get caught in traps.

跟蹤練習(xí)：

Which of the following does NOT put manatees in danger？

A. Human activities. " " " " " B. Other animals.

C. Poisonous sea grass." D. Sickness.

Key：B