Common Frog

Rana temporaria - Common Frog
An all time favourite of children in the garden is the Frog, their interest is increased when finding frog spawn and later tadpoles in the pond. Frogs spend the vast majority of their time on dry land in the shrubbery or under stones etc. returning to the pond to lay their spawn. In the wild frogs live for up to 8 years and an adult is between 6 and 10cms long, weighing approximately 23gms. Females are usually slightly larger than the males which tend to be slightly darker in colour.

The males can be distinguished from the females by the blueish-black pads on their first fingers pads (nuptial pads). These pads become more pronounced during breeding season and are used by the male to cling on to the female. The frogs can vary in colour from grey, olive green to yellow or brown and have smooth skin. Their undersides are usually white or yellow but sometimes orange in females. These frogs can also lighten or darken their skin colour to blend in with their environment better. Their eyes are brown with black horizontal pupils and a transparent inner eyelid to protect their eyes when under water. The common frog can also breathe through its skin and this enables it to hibernate beneath mud and decaying matter underwater.

Common Frogs lay their spawn in the shallows of ponds in early spring (Late Feb early March). The spawn is surrounded by a jelly like substance which swells up in the water to protect the embryo. The eggs hatch after 30 to 40 days and the tadpoles emerge from the jelly which they then feed on for the first few days before moving on to algae. It takes about 12 to 14 weeks for the tadpole to change into a frog. On average only about 5 out of 2000 eggs survive the cyle to adult frogs. Tadpoles emerge with gills which enable them to breathe under water, they lose these after about 9 weeks and then have lungs so need to breathe from the surface. Hind legs develope after about 8 weeks and front legs after about 11 weeks.

As they grow tadpoles feed first on the jelly then algae followed by small insects and plants. adult frogs feed on insects, snails, slugs and worms, which they catch with their long, sticky tongues. Adult frogs feed entirely on land. Although they do not feed during the breeding season.

Protected in Britain under Schedule 5 of the Wildlife and Countryside Act (1981), with respect to sale.

Links for browsers without support for frames Table of Contents. Home Page.