The following was originally published as the sidebar text accompanying the above photo for November in the 2017 Boundary Waters & Quetico calendar.
It’s time to winterize, and the herps (reptiles and amphibians) of Canoe Country have remarkable adaptations to winter weather. They brumate, rather than hibernate, which means they reduce their metabolism so much that they do not need to eat, and only use very little oxygen. They metabolize so little that they may even maintain their weight all winter. Frogs, toads, and salamanders take in what little oxygen they need through their skin rather than their lungs. Frogs that live mostly in water spend most of their time lying camouflaged on top of the muck on the lake bottom. The rotting matter gives off a bit of warmth, which helps them survive. Salamanders dig into mud along shores or in swamps, far enough down to avoid frost. There they remain dormant until spring. Terrestrial frogs and toads dig into warm (relatively) composting heaps of organic matter in forest or wetlands. Wood frogs, and perhaps other herps (study is still under way), change their body chemistry to create an anti-freeze that keeps their vital organs viable even when their body temperature goes well below freezing. Turtles bury themselves in mud at the lake bottoms, usually a foot or two below the frogs. They absorb oxygen through their skin — especially the highly vascularized tissue of their cloaca (which the dictionary daintily defines as an area at the end of the digestive system where excretory wastes and genital products are released). Garter snakes gather in massive groups (1,000s in some places) in a dark cave or hole that stays about freezing. All herps are slow-moving or still in the cold, but some remain alert through the winter.
