This is the iced-in pond at WoodenBoat yesterday, now swept gracefully by an additional layer of snow from last week’s nor’easter. Its beauty belies a danger if the pond stays completely covered like this.
The danger is “winter kill,” when a pond or lake is covered by a suffocating blanket of ice or – worse – covered by ice that is sealed with snow that extends beyond the pond’s edge. The tight cover prevents the natural exchange of gasses. The oxygen in a pond is finite; hibernating turtles and frogs, fish, and vegetation below the ice and snow can be suffocated unless the oxygen is renewed. (Image taken in Brooklin, Maine, on February 1, 2022.)