Wood Frog

Wood Frog

Almost like the masked bandit or an amphibious raccoon, the Wood Frog also has dark patches around its eyes. Found as far south as Alabama and as far north as the Arctic circle (they are the only species that lives this far north), the Wood Frog has a massive range. It is found in every province and territory in Canada as well as Alaska. The habitats that they like best are woodlands, hence the name. Their colouration, also varied, provides perfect camouflage to blend in with the leaf litter.

They prefer to lay their eggs in vernal pools or vernal ponds. This bodies of water are pools or ponds that don't last the whole season. This means that fish usually cannot survive in the which provides the tadpoles a bit more safety while growing. However, the still have to worry about immature dragonfly larvae as well as salamanders and even other wood frogs.

AS adults, the frogs have to watch out for a number of snakes, birds and other opportunistic predators like raccoons, snapping turtles, coyotes and foxes.

Wood Frog

One truly fascinating thing about these frogs is their overwinter strategy. Since they are the only frog to live north of the Arctic Circle, their plan for surviving the cold must be as extreme as the weather they face. Some frog species dig themselves underground but the Wood Frog doesn't. The Wood Frog instead crawls into the leaf litter and let the cold take it. Yes, the Wood Frog lets itself be frozen....solid...yes, seriously. The frog produces a special antifreeze in the cytoplasm of their cells. The cytoplasm is the fluid inside the cell. This stops the cells from freezing. When a fluid freezes, it expands (just look at water) and then the cell walls burst as the cytoplasm expands. However, since the Wood Frog's cytoplasm doesn't expand, the cell walls don't burst. However, the interstitial fluid, or the fluid between the frog's cells, freezes solid. So for us the frog looks frozen, and it effectively is. Even though the fluid in the cells isn't frozen, they are still the same temperature as the frozen fluid outside the cell, at this temperature, all the cells chemical processes stop. The metabolism, the heart stops pumping and the frog stops breathing. For the winter, it is functionally dead.

However, when spring comes the frog starts thawing, the interstitial fluid thaws as well and eventually the temperature rises enough to provide enough energy to restart the chemical processes within the cell and the frog is revived. Since none of the cells burst, they are relatively undamaged from the ordeal. Truly fascinating behaviour and skill. To effectively raise itself from the dead.

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