One of the cottage rituals for most owners is to take out the docks in the fall and put them back in once spring arrives. If you don't, there is a danger on some lakes that moving ice will crush the docks or tear them from their moorings and allow them to drift away down the lake.
We've got ours pretty systematized now. In the fall, we disconnect the floating sections from the fixed dock and float them down the shore to a very protected bay. There they're protected from wind and shifting ice by several small islands. We lift up the fixed dock so the feet are above the ice level during the winter.
In the spring the process is reversed... lower the fixed dock, float the platforms back over and reattach to the weights which rest on the lake bottom and hold the docks in place with chains.