The common frog is one of Britain’s best known amphibians and can be found across the UK. These semi-aquatic animals are usually seen in shallow ponds in spring as they congregate to reproduce, although they actually spend half the year on land.
Frogs spend the winter hibernating in sheltered spots in gardens, grassland and woodland under rocks, logs and in leaf piles. They can also hide in the mud at the bottom of ponds to hibernate because they can breathe in water through their skin!
Scientific name: Rana temporaria
Appearance: smooth moist skin, greenish brown colour, dark patch behind the eyes, long striped legs
Length: 6 - 10cm
Frogspawn: free-floating clumps of up to 200 eggs in ponds and non-moving water bodies, distinctive black dot in the centre of each egg
Common frogs are aquatic during the mating season from February to June, when they live in ponds and seasonal water bodies. During the rest of the year, frogs are largely terrestrial, which means that they live on land. They can be found in damp places such as marshes and grassland. Garden ponds are vital for common frog populations. Over winter they shelter under rocks or logs, at the bottom of ponds and in compost heaps or leaf piles for hibernation.
The diet of the adult common frog is made up of invertebrates such as snails, slugs, worms and insects. Common frog tadpoles feed mainly on algae in the water.
Breeding occurs in early spring, when adults emerge from their overwintering location and travel to a pond. Once mated, females lay clumps of spawn in the shallow waters of the pond. After around 30 – 40 days, black tadpoles will emerge and change to a speckled-brown colour as they develop. Metamorphosis into froglets begins at around 16 weeks old when their back legs start to grow, shortly followed by the front legs. The final stage of this change occurs when the tail is fully absorbed and the froglets leave the water to begin the terrestrial phase of their life.