they can't cross open oceans. 它们也无法横渡广阔的大海

161. The lucky survivors can begin learning the unique way of life
     有幸活下来的小鬣蜥可以开始学习
162. demanded by this hostile island.
     应对这座危险岛屿的独特方式了
163. Although marine iguanas are expert swimmers,
     尽管海鬣蜥是游泳的行家
164. they can't cross open oceans.
     它们也无法横渡广阔的大海
165. But even the stormiest waters are no barrier for birds.
     但再汹涌的海水都无法阻挡鸟类
166. Gale force winds and cold temperatures
     阵阵烈风加之低温
167. make the subantarctic islands off New Zealand
     让新西兰亚南极地区的这座岛屿

来自《行星地球 第二季 第一集 Planet Earth S02E01 岛屿》第 164 行