Wood Frog

Wood Frog Facts
Size 2 - 2.7 inch (51 - 70 mm)
Speed Unknown
Weight Up to 0.28 oz (8 g)
Lifespan Up to 3 years
Food Little vertebrates
Predators Snakes, herons, owls, raccoons
Habitat North America, Alaska, Canada
Class Amphibians
Order Anura
Family Ranidae
Scientific name Rana sylvatica
Characteristics Survives very cold temperatures below zero degrees Celsius

The wood frog is an amphibian living in the woods of North America..

The Frozen Frog

If temperatures are below 32 degrees Fahrenheit (0 degrees Celsius) for some time, not only the ground freezes but also the wood frog! This might be rather unpleasant, but, what’s more, it does not breathe and its heart does not beat until springtime!

In order not to die during the cold period, the frog pumps a lot of glucose (sugar) and urea into its body. Both substances prevent the formation of lethal ice crystals in the body cells.

Wood Frog Wood Frog - Photo: Chris Hill/Shutterstock

Not more than 65 %
And not Colder than 21 degrees Fahrenheit (-6 degrees Celsius)

This trick has its limits of course. If more than 65 % of the frog’s body liquids freeze, not even the wood frog would be able to survive. It also must not get too cold.

During its torpor, the body temperature of the wood frog lies between 30 and 21 degrees Fahrenheit (-1 and -6 degrees Celsius). If it were colder than 21 degrees Fahrenheit (-6 degrees Celsius), the wood frog would also have to give up. Brrr! This is simply too cold!

The wood frog is not the only animal that lapses into torpor. Fish, lizards, turtles and insects do, too.

"Zorro in the Woods"
How to recognize a wood frog

There are 260 “true frogs” among 5,800 species of anurans (= frogs and toads). It is not always easy to instantly distinguish between them, especially when they are quickly hopping past you. Yet, it easy to recognize a wood frog with its distinctive dark eye mask.

Wood Frog Wood Frog - Photo: Steve Byland/Shutterstock

The Wood Frog and its Age

The little chap has not got much time to reproduce. Normally it reaches an age between 2 and 3 years. After about one year, the male frogs are ready for mating, the females after two years.

A Whole Lot of Frogs

The wood frog’s clutch of eggs is directly under the water surface and consists of 2,000 - 3,000 eggs. The little wood frogs hatch after 10 to 30 days.

Wood Frog Wood Frog - Photo: steve52/Shutterstock

Wood Frog Wood Frog - Photo: Marek Mierzejewski/Shutterstock


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