Alternative common names:
The marsh frog is the largest species of true frog native to Europe and is found in deep ponds, lakes, rivers and around streams across the continent. The diet of the marsh frog consists ofdragonfliesand other insects,spiders,earthworms, andslugs. Larger frogs also eat small rodents and sometimes smaller amphibians andfish.
Where does this species come from?
What is its invasive status in South Africa?
NEMBA Category 1b.
Where in South Africa is it a problem?
How does it spread?
Dispersed along waterways at original site.
Why is it a problem?
It’s quite voracious and in fish ponds, it eats small fishes and often eats conspecific and other amphibians, as well as reptiles and even small birds and rodents.
What does it look like?
Description: Marsh frogs can grow to 13 cm or more. It’s a robust, warty frog with a wide mouth and close-set eyes; long hind legs with heels extending beyond head; the metatarsal tubercle is small with a low profile. It is variable in colouration but typically has a brown/grey dorsal surface with greenish tinge and green/olive on back with dark spots. Thighs are striped/spotted greyish/white. It has dark grey vocal sacs, unlike the Edible frog (light grey) or Pool frog (white).The dominant colour can be bright green or (rarely) blue. Females do not possess vocal sacs or develop metatarsal tubercles. The Marsh frog can be mistaken for other water frogs .The Edible frog has a variably coloured dorsal stripe, narrower gape, light grey vocal sacs and its slightly shorter legs reach to between eyes and nares .Pool frogs are much smaller, have short legs reaching only behind the eyes and the males have white vocal sacs. Marsh frog males also develop a yellow facial colouration in the breeding season
Habitat: These aquatic animals prefer large, deep ponds, lakes and rivers and are tolerant of slight salinity as found in upper estuarine conditions. Requiring insolation they are usually found gregariously sunning on south-facing banks adjacent to the water body or on floating rafts of vegetation on the water body. On disturbance, they leap into the water with a characteristic.
Breeding: Breeds in the early spring, when mating takes place in calm, shallow pools of water. The female marsh frog lays around 1,000 eggs in a sticky cluster that floats on the water’s surface, known as frogspawn. Once developed the marsh frog tadpoles emerge into the water where they are fully aquatic until they metamorphose into adult marsh frogs and are able to leave the water.