Wood Frog (Lithobates sylvaticus)
The Wood Frog is a fascinating amphibian, notable for being one of the first frog species to emerge in spring. This remarkable species possesses freeze-tolerance capabilities and shows a preference for vernal pools during breeding season. Their early emergence and unique adaptations make them an intriguing subject for wildlife observation.
| 🇫🇷 | Grenouille des bois |
| 🇩🇪 | Waldfrosch |
| 🇲🇽 | Rana de bosque |
| Taxonomy | |
| Order | Anura |
| Family | Ranidae |
How to Identify
The dark eye mask is a distinctive characteristic of this species. This mask, resembling a robber's mask, extends from the eye to the base of the front leg and makes the Wood Frog easily distinguishable from other local frog species.
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Characteristics
| Length | 5-8cm |
| Weight | 10-15g |
Videos
Videos are hosted on YouTube. Click on a thumbnail to watch it.
Where and When to Spot
My first observation of this species has been a few years back in Parc Nature Pointe aux Prairies early spring in a pool which still was partially frozen. I returned to the same place on several occasions around the same month. In April 2022, I finally encountered them again and recorded a video.
Observation Records by Park and Season
| Location | Spring | Summer | Autumn | Winter |
|---|---|---|---|---|
| Parc Michel-Chartrand | x | - | - | - |
| Parc Nature Pointe aux Prairies | x | - | - | - |
"x" indicates the species was observed, while "-" indicates no observation. Lack of observation doesn't necessarily imply that the species is absent. Data is derived from our park visit journals.
Questions & Answers
Delve deeper into distribution, habitat, behavior, and ecological role of the Wood Frog (Lithobates sylvaticus). Click on a question to uncover the answer.
How do you recognize a wood frog in the wild?
The wood frog has a distinctive black "mask" across its eyes, a brown or tan body with a lighter underside, and a dark ridge along its back. It typically grows between 5 to 8 cm in length and has a slightly pointed snout.
What is the life cycle of a wood frog?
Wood frogs lay eggs in early spring in temporary ponds; the tadpoles hatch within weeks and develop into froglets in about two months. They reach adulthood within two to three years and live for up to five years.
What is the natural habitat of the wood frog?
Wood frogs are found in forests, wetlands, and near temporary ponds across North America, particularly in Canada and the northern United States. They prefer cool, moist environments and rely on seasonal pools for breeding.
When and where do wood frogs breed?
They breed in early spring, often immediately after ice melts, in temporary ponds or vernal pools. Males call to attract females, who lay large clusters of eggs that hatch within a few weeks.
What do wood frogs eat, and how do they find food?
As tadpoles, they primarily consume algae and organic debris, while adults feed on insects, spiders, worms, and other small invertebrates. They hunt by ambushing prey using their quick reflexes and sticky tongues.
What are the main predators of wood frogs?
Eggs and tadpoles are eaten by aquatic insects, fish, and salamanders, while adult frogs fall prey to snakes, birds, mammals, and larger amphibians. Their high reproductive rate helps sustain populations despite heavy predation.
How do wood frogs protect themselves from predators?
Their brownish coloration provides camouflage among leaf litter, and they remain motionless to avoid detection. If threatened, they may leap away quickly or emit distress calls to startle predators.
How do wood frogs survive freezing temperatures?
They produce glucose and other cryoprotectants that prevent ice from damaging their cells, allowing them to survive even when most of their body water freezes solid. This unique adaptation enables them to withstand extreme winter conditions better than most amphibians.
What role do wood frogs play in the ecosystem?
Wood frogs help control insect populations and serve as food for various predators, contributing to a balanced ecosystem. They also support wetland health by cycling nutrients and influencing aquatic food webs.
Is the wood frog an endangered species, and what threats does it face?
The wood frog is not currently endangered, but habitat loss, climate change, pollution, and disease threaten populations in some areas. Conservation efforts focus on protecting wetlands and maintaining healthy forest habitats.