"Several days went by and still there was only ice in sight. He was in no danger as long as he could get his head out of the water, but he was starting to notice that this was becoming harder to do. The breathing hole was getting smaller and smaller as the water in it began to freeze over. He kept it open by butting his head against the newly formed ice, but it was a loosing battle and one day he could only get his snotter into the air. If something didn’t change soon, his last contact with the air would be lost and he would surely drown."
"Sharkface was once again in a state of despair; he couldn’t think of any way out of this mess. Soon the breathing hole would close and he would be forced to go looking for another one. If he couldn’t find it in an hour or so, it would all be over. He thought of the warm beach on Guadalupe and all his elephant seal friends. He thought of Cuvier and Topsy and her long, gossipy tales. He thought of George and the octopus and of Bennie and his broken tusk. He was going over all his great adventures and had just about decided that if this was how it ended, it was OK. He had lived a long and adventurous life and … then he heard a noise."
from Chapter XI, Sharkface Crosses the Frozen Sea