Because of its salt content, the water in ocean and brackish areas freezes at lower temperatures than fresh water in bogs. That sea ice can be very thick and seem to be safe to walk on, but temperature swings and tidal action can cause hidden faults that crack open suddenly when you walk on it.
Bog ice in cold weather also can shatter from your weight and make you stumble into freezing wet goo with disastrous results. Last month, a man in Cutler who was in the woods alone reportedly fell through bog ice. He got soaked, became extremely cold and disoriented, lost his way, and started to get hypothermia. A Maine Warden Service rescue team found him in time to save his life. (Images of sea ice taken in Surry, Maine, on February 9; image of bog ice taken in Brooklin, Maine, on February 10, 2023.)