They spent 30 minutes on the bottom of the world before surfacing with their glass viewing ports cracked by the pressure .
在玻璃观察窗因为水压而破裂，最终浮出水面以前，他们在世界的底部逗留了30分钟。
The animals were matched with their calls by their surfacing locations and swim speed , as well as by digital cameras while they were near the surface .
