There are only about 1,000 Hawaiian monk seals(夏威夷僧海豹) left and its population is going down 4% a year. Hawaiian monk seals are found in the northwest part of the Hawaiian Islands. They spend a lot of time at sea. They are able to dive 600 feet deep, and can stay under water for up to 20 minutes. Adults grow up to seven feet long, and weigh between 400 and 600 pounds. They can live as long as 30 years. These seals are born on land. Every year, usually in May or June, females find sandy beaches and give birth to a single baby. The female seals avoid beaches where the water becomes deep very quickly because this lets sharks swim close to land and catch the seals. Mothers stay with their babies for six weeks. During that entire time, they do not leave the beach even to eat. Instead, they live off fat that they have stored up over the previous year and feed their babies with fat-rich milk. After six weeks, mothers go back to the sea. The young have to live on their own. Human disturbance(打扰) has been regarded as the important factor in the decrease of the monk seals. In fact, if human come too near a mother seal too often, she will go out to the sea. Unfortunately, this usually means death for the baby. It is now against the law for people to come within 100 yards of a seal on a beach. Recent research has shown that the decrease in the Hawaiian monk seal population is due to lack of survival of these seals at one of the most important breeding(繁殖) beaches at French Frigate Shoals. Also, seals often get trapped in fishermen and by changes in weather patterns. If these threats(威胁) were not enough, during the breeding season, males will attack females until they are badly injured or finally killed. 小题1:What can we learn about Hawaiian monk seals?
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