Two years ago when paddling down the Churchill River, we found a fat old porcupine leisurely crossing the river where it was over a mile wide. He was then about eight hundred yards from where he wanted to land and his speed must have averaged one mile per hour. He took absolutely no notice of us. At each stroke of his short foreleg he grunted loudly. Now and then he would lift his quills and shake them so as to get some of the weight of the water off his back.
Squirrels, I have noticed, always swim with the wind in their backs and invariably carry their tails straight up in the air out of the water.
The Indians maintain that they only take to water when the wind is favorable as they know that their tail, acting like a sail, will help them along.
White Bears, of course, are the best swimmers of all the non-amphibious mammals. They can swim for a whole day, resting now and then on their backs like sleeping seals.
In 1908, we saw a White Bear yearling cub swimming towards shore at least fifteen miles out from Cape Churchill in Hudson Bay. The nearest ice was then forty-five miles from the spot where we found him. There was absolutely no doubt that our bear had undertaken a sixty-mile swim to reach land.