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The Hazen's Notch Association is a non-profit conservation
organization located in montgomery center, vermont.
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provides environmental education programs for schools, conducts a
summer camp for children, maintains a network of trails for
cross country skiing, snowshoeing and hiking on 2,500
acres of land and serves as a local land trust.
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AMPHIBIANS
Wood Frog
Rana sylvatica
 The Wood frog is one of the earliest amphibians to emerge from the Winter season. Even before the snow has completely melted from the edges of ponds and wetlands, one can hear its duck-like quacking sound, an indication that they are in their brief breeding season in early to mid-April. The Wood Frog is the only North American frog to occur north of the Arctic Circle; and has developed an amazing metabolic capacity to survive very cold and very long winters.
Size/Reproduction
The Wood Frog is a small to medium-sized frog (1 3/8” – 3 ¼”) that is brown to tan to pinkish in color. The frog is easy to identify by the dark mask on the side of the face that runs from the nose to just behind the eye. After transforming from tadpole to adult, tiny frogs disperse throughout moist woodlands in the East (open grasslands in western regions and the tundra in the far north). One female frog may lay 2000 – 3000 eggs in a season and places them in globular masses attached to submerged twigs in ponds or free in vernal pools.
Winter Survival
The Wood Frog has evolved to be able to spend the Winter months just under forest leaf litter and actually freeze solid. During Fall, the frog cools down gradually. When frost threatens to freeze water inside the cells (which would cause death), the frogs adrenal system floods the blood with adrenalin which then triggers a huge increase in glycogen. The sugar draws water from the cells and places it in between the cells. The frog then stops breathing and its heart stops beating. In Spring, when the temperature reaches 50 degrees where the frogs are, the process is reversed; water enters back into the cells and the frog resumes breathing and its heart starts beating.
- Deborah Benjamin
 Habitat: Ponds, marshes, vernal pools, & ditches with deep standing water.
 Wildlife Observation Tips
To hear and see Wood Frogs, one must approach a pond very stealthily, and listen for the duck-like croaking, which can be heard for long distances and may include hundreds of individuals. If one frog sets off an alarm croak, all of the frogs will instantly stop croaking and disappear into the leaves and mud.
If that happens, stand still for a few minutes and disguise your presence by lowering yourself out of view or by standing behind a shrub. Eventually, the urgency of completely the breeding cycle will compel the frogs to start croaking again; first one and then another will sing and then the whole pond will once again be a din of frog sound.
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This page was last updated on January 25, 2008
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