Scientists say there has been a major drop in the population of leatherback sea turtles off the U.S. West Coast. 科学家说，美国西海岸的棱皮海龟人口大幅下降。 

Researchers say there was an 80 percent drop in one group of leatherbacks found off the California coast over the past 30 years. One recent study found a 5.6 percent yearly decrease in the population. 研究人员说，在过去30年中，加利福尼亚海岸在加利福尼亚海岸发现的一组棱皮术下降了80％。 最近的一项研究发现，人口年度下降了5.6％。 

Leatherbacks are massive sea turtles dating back to the time of the dinosaurs. The animals can grow up to 1.5 meters in length and weigh as much as 680 kilograms. 棱皮是可以追溯到恐龙时代的巨大海龟。 这些动物的长度长达1.5米，重达680公斤。 

The leatherback sea turtles found along the U.S. Pacific coast are actually born thousands of kilometers away, on beaches in Indonesia, Papua New Guinea, Vanuatu and the Solomon Islands. The animals migrate 11,000 kilometers across the Pacific Ocean to feed on jellyfish in waters off the U.S. West Coast. Then, they swim back. 沿着美国太平洋海岸发现的棱皮海龟实际上诞生于印度尼西亚，巴布亚新几内亚，瓦努阿图和所罗门群岛的海滩上数千公里。 这些动物在整个太平洋上迁移了11,000公里，以美国西海岸海水中的水母为食。 然后，他们向后游回。

As many as 60 percent of the leatherback turtles born in the western Pacific Ocean are believed to make the trip to California. Scientists are not sure why some do and others do not. Some go farther north, to waters off Oregon or Washington state. 据信，在西太平洋出生的棱皮龟中，多达60％是前往加利福尼亚的旅行。 科学家不确定为什么有些人这样做，而另一些人则不知道。 有些人向北走得更远，到达俄勒冈州或华盛顿州附近的水域。 

Scott Benson is an ecologist with the U.S. National Oceanic and Atmospheric Administration's (NOAA) fisheries service in Monterey, California. He has studied the turtles for many years and recently co-wrote a study on leatherback populations. Benson told The Associated Press that the long trip across the Pacific demonstrates the strength of the sea turtles. 斯科特·本森（Scott Benson）是加利福尼亚州蒙特雷的美国国家海洋和大气管理局（NOAA）渔业服务的生态学家。 他研究了乌龟多年，最近共同撰写了一项有关棱皮师人群的研究。 本森告诉美联社，穿越太平洋的漫长旅程展示了海龟的力量。

“There are birds that go farther, but they fly. There's a whale shark that might swim a little further, but it doesn't have to come up for air,” he said. The leatherbacks, he noted, are “actually pushing water all the way across the Pacific Ocean.” 他说：“有些鸟会走得更远，但是它们会飞。有一条鲸鲨可能会走得更远，但不必升起空气。” 他指出，棱皮的背包“实际上是在太平洋上一直推着水。”