Yikes.
Yes, people with cottages and cabins that don't heat them have to winterize. Boats, jetskis, etc.
One of my boyfriends bosses has a small man made patio pond with huge koi fish. I'll have to ask when they do with those. Obviously bring them in, but I don't recall seeing any large aquariums in their house. hmmm
22 degrees this morning, so those that procrastinated with getting ready might be in trouble come spring. But, sometimes it needs to be sustained long periods of below freezing weather to do harm. It'll come, but not just yet.