看看这些“海牛”(Check out these ‘sea cows’)

今天是海牛欣赏日，这一切都是为了珍惜和帮助这些温和的生物。考虑到它们甜美友好的天性，很难不爱它们。这些哺乳动物每天在河流和沿海水域缓慢觅食长达7个小时，消耗其体重的10-15%。它们确实有牙齿，但不用担心，它们都是用来磨碎水生植物的扁平臼齿。在他们的一生中，他们在口腔后部长出新的牙齿，然后向前移动，取代旧的牙齿。海牛很好奇，对和人类一起玩很感兴趣，但我们的存在使它们面临意外接触船只和人造建筑的风险。20世纪70年代，它们在美国的数量已经减少到几百只，但通过保护工作，它们已经恢复到6000多只。如果我们想在未来几年欣赏脆弱的野生动物，保护它们至关重要。
原文：
Today is Manatee Appreciation Day, which is all about treasuring and helping these gentle creatures. Given their sweet and friendly nature, it’s pretty hard not to love them. These mammals slowly graze through rivers and coastal waters for up to seven hours a day, consuming 10-15 percent of their body weight. They do have teeth, but fear not, all of them are flat molars used for grinding up aquatic plants. Throughout their lives they grow new teeth at the back of their mouth which then move forward, replacing the older ones. Manatees are curious and interested in hanging out with humans, but our presence puts them at risk of accidental contact with boats and manmade structures. Their numbers in the US have dwindled to a few hundred in the 1970s, but through conservation efforts they’ve grown back to over 6,000. Protecting our vulnerable wildlife is crucial if we want to be able to appreciate them for years to come.
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