So in a normal year, they start laying their eggs right after arrival.

“在正常年份，它们一到达北极就开始产卵。

They will also need to do a viral test three to five days after arrival.

在到达美国后的3至5天内还须再次进行检测。

But they have to present a negative test result from within 48 hours, and complete two tests within three days after arrival.

但必须持 48 小时内核酸阴性检测结果，并在抵达后三天内完成两次检测。

The National Health Commission says passengers traveling to China need to take nucleic acid test within 48 hours before boarding their flights to China, adding that nucleic acid screenings and centralized isolation after arrival will be canceled.

国家卫生健康委员会表示，来华旅客需要在登机前 48 小时内进行核酸检测，并取消落地后核酸筛查和集中隔离。