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Frogs are a common sight in garden ponds and woodland streams, and frogspawn and tadpoles are familiar to most of us from childhood.

Frog with head out of water

Outside of the breeding season, frogs spend most of their time on land. They can be spotted among tall plants in meadows and woodland. On warm, damp evenings, they come out to hunt insects, which they catch with their long, sticky tongues.

In the spring, frogs become aquatic. They breed in any area of still, shallow water, including puddles, ponds, streams, lakes and canals.

Frogs are cold-blooded and can't function when the outside temperature drops too low. Common frogs, the species found in the UK, hibernate during the winter. They do this either under logs on land or at the muddy bottom of a pond. Frogs are able to breathe through their skin and can therefore happily spend several months underwater, beneath piles of mud or leaves.


Frogspawn is the name of the clumps of eggs laid by frogs. It is a jelly-like substance, and if you look closely you will see that every egg has a tiny black dot in it. This is the developing frog.

The time it takes for frogspawn to develop can be anything from a couple of weeks to a few months, depending on the temperature. The black dots get longer and takes on an eel-like appearance before turning into a true tadpole, then a froglet. Once the tadpoles have emerged from the frogspawn they will eat it before moving on to other food sources.

It's estimated that a female frog can lay up to 4,000 eggs at one time, although few of these will survive to become frogs.

Frog facts

Appearance: Frogs have a sturdy body with strong back legs and webbed toes to help them swim. Usual colours are green, brown and yellow, but this can vary. Sightings of pink, orange and even albino frogs have been reported. The skin of a common frog is very smooth and generally covered with irregular dark blotches. Eyes and nostrils are positioned on the top of the frog's head, so they can see and breathe (through their nose) when the rest of their body is underwater

Size: 6-10cm. Females are usually slightly larger than males

Weight: Approximately 22 grams

Lifespan: Up to 8 years in the wild

Diet: Adult frogs feed on moving invertebrates such as insects, snails, worms and slugs. Tadpoles are herbivorous and feed only on algae

Family: Ranidae

Family nature guide 2019

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Identify footprints and read fascinating facts about the creatures who make their homes along our canals and rivers

Last Edited: 16 November 2020

photo of a location on the canals
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