Saturday, 04 February 2012

Marsh Frog

Primary Image: 
Facts
Scientific Name: 
Rana ridibunda
Lifespan: 
up to 11 years
Length: 
100-120 mm
Information
Description: 

Adults up to 15cm rarely up to 18. the largest native European frog, big, robust and sometimes rather warty. Vocal sacs grey and back of thigh spotted whiteish grey (only rarely yellowish).

Distribution: 

Mainly south east England though this species is spreading

Habitat: 

Marsh Frogs are more tied to aquatic habitats than its cousin the common frog. It is tolerant of brackish conditions and, typically, it is found on or in the water of its favoured drainage channels and pools throughout the year.

Behaviour: 

Usually gregarious, diurnal and very aquatic; but also active at night and occasionally found some distance from water. Frequently sunbathes on the bank of the water body where it is often inconspicuous until disturbed, it jumps into the water with a characteristic ‘plop’. Often seen on lily pads or floating at the surface amongst vegetation with only its head exposed. Usually hibernates in winter in the mud at the bottom of the pond.

Reproduction: 

During the breeding season, (and sometimes beyond), the male marsh frog calls very loudly with a sound reminiscent of a loud chuckle often very raucous and can be heard all day and night. Dominant males establish territories covering several square metres of water surface from which they call. After mating a female may produce up to 16,000 eggs in a season, laying them in clumps of a few hundred in aquatic vegetation below the surface. They hatch in about a week, tadpoles being rather solitary and living in deep water with vegetation, sometimes over-wintering as tadpoles. Newly metamorphosed frogs are 1-2.5cm in length and take two years to mature.

Status: 

The marsh frog is native to mainland Europe and its status in Britain is that of an introduced alien. Within its restricted range it is locally common

Did You Know?: 

Marsh frogs are relatively easy to see if you visit one of their known haunts though you may have to be stealthy - the Lewes Brooks in Sussex and Romney Marsh in Kent are strongholds. Imitating the call of the male can sometimes trigger a responding chorus from nearby individuals, (though people will look at you very strangely).