Page 2 of 6. Frequently asked questions.

Common frog Rana temporaria

Description

The most familiar of our amphibians, the common frog can attain an adult length of up to around 10cm. Frogs are very variable in their colouration and markings; most are greenish, brown, or grey, but yellow, orange and red frogs do occur. Unlike toads, there is a dark "mask" immediately behind the eye, and the skin is smooth and moist. Frogs are widespread across the UK and Ireland, are the commonest of our amphibians, having undergone increases in some areas, probably due to colonisation of new garden ponds. However they are probably declining in the wider countryside where pond loss continues.

Legal protection: sale and trade prohibited

Frog spawn and adult frog

[NOT TO SCALE]

Life history

Frogs lay clumps of eggs in ponds in February-March. Tadpoles hatch out and feed on algae, progressing to a diet of plant and dead animal matter. The rear limbs develop first, and metamorphosis finishes when the tadpole possesses all four limbs, leaves the water and the tail is resorbed. The process of development from egg to froglet takes around 12 weeks but depends very much on temperature. Males can reach maturity after two years, females after three, and often return to the same pond to breed. Adult frogs are carnivorous, feeding on almost any small invertebrate. Hibernation occurs from around November to February.

Critical Factors - frogs require:

Ponds for breeding - generally shallow ponds, possibly ones that dry up in summer. Spawn develops best in sunny shallows (no more than 30cm deep).
No fish - spawn and tadpoles are eaten by fish, and frogs do better without them.
No waterfowl - spawn, tadpoles and aquatic plants are eaten by waterfowl, and frogs do better without them.
Aquatic vegetation and invertebrates to feed tadpoles
Easy exit from the pond for emerging froglets and adult (i.e. no steep sides)
Damp, vegetated areas around the margins for cover and emerging froglets.
Areas of rough, preferably damp, grass for foraging and cover
Daytime refuges, such as logs, rocks and shrubby vegetation
Areas of woodland or similar habitat for hibernation.

Frog tadpole

(Provided by and reproduced with permission of: English Nature)