I just got this from a friend as a forward, but it is not uncommon stuff around here. These four deer were picked up swimming, and were later released on shore. Apparently, they were hypothermic and exhausted and approached the boat, and then let themselves be picked up out of the water.
I personally have come across deer swimming many times, sometimes crossing bodies of water over a mile across.
I have a friend who once rescued a deer that was coming to his boat, and he looked to the nearest land and saw a wolf on the beach, which may explain why some of this swimming happens in the first place...