Frogs in South Africa
The world’s frog population is varied and diverse. Scientists believe that there are over 4 000 different kinds of amphibians on Earth. Frogs form a part of this group. In South Africa, we have our own large variety of frogs, which ranks us 27th in the world of amphibian species richness.
This means that frogs like to call South Africa home. You can find the giant bullfrog, which grows up to 245mm in length, and you can also find the tiny northern moss frog, which is a mere 14mm in size. We also have a colourful frog selection, such as the painted reed frog, the rubber frog species and the Tree frog species.
It comes as no surprise that KwaZulu-Natal has the largest number of frog species in SA. This is because of the forest-rich areas that you can find in this province. Different species can thrive in a range of different habitats, including aquatic, such as the platanna; arboreal, the tree and reed frogs; fossorial, rain frogs and shovel-nosed frogs; and the terrestrial toad species.
Frogs and their Evolution and Life – Cycle
Table Mountain Ghost Frog
Heleophryne rosei
- Only found in perennial streams on the eastern southern slopes of Table Mountain.
- About 63mm in length.
- Critically Endangered.
- The tadpoles have to adapt for life in fast-flowing mountain streams therefore they have a sucker-like mouth to help them
- The genus occurs only in South Africa.
Giant Bullfrog
Pyxicephalus adspersus
- Seasonal, shallow grassy pans in open flat areas of grassland or savanna.
- Up to 245mm in length.
- Have three odontoids (teeth) on lower jaw.
- Males are bigger than the females.
- A female lays up to 4000 eggs.
- Tadpoles form schools.
- The males have paternal care.
- Cannibalistic.
Giant Bullfrogs can weigh up to 1,4kg
Bushveld Rain Frog
Previcepes adsperus
- Fossorial species (adapted to dig holes).
- About 60mm in length.
- Cannot swim.
- Lay eggs in a subterranean egg chamber, not in water.
- Females are more than double in size of males.
- The genus only occurs in Southern Africa.
- Lives in the grassland and savanna biome of Southern Africa.
Foam Nest Frog
Chiromantis xerampelina
- Arboreal (lives in trees).
- Maximum size 8555mm.
- Often found in bathrooms or verandas in the Kruger National Park or other bushveld areas.
- Can change colour to white to reflect light and heat.
- Form foam nests above water.
- Many males and a female form a foam nest together.
- After 4-6 days the tadpoles drop into the water.
- Bushveld area of Southern Africa.
Common Platanna Frog
Xenopus laevis
- Totally aquatic.
- Up to 147mm in length.
- The tadpole looks like a small barbel fish.
- Only frogs with claws in Southern Africa.
- The genus only occurs in Africa.
- Occurs in most of South Africa.
Between the 1930s and the 1950s, live South African platannas were used around the world to determine if women were pregnant. This process was called the Hogben Test.
Importance of Frogs
Though most of us have not paid much attention to frogs, it’s time to take note.
These animals play an important role in the environment:
Frogs are indicator species. Their skins are permeable, which means that things can pass through them. They can absorb most things in the environment through their skin. Frogs can show us if the environment is contaminated with pollution because their health would be affected. Their ability to both live on land and water helps scientists to determine the health of the ecosystem of the area. They are important to the food chain. Frogs are both predators and prey, which means that they feed on algae, as tadpoles, which keeps the water clean, and, once fully – grown, they feed on insects (which controls the bug population). They are also the meal of choice for animals like fish, snakes and birds.
Frogs in Danger
Despite their importance to the environment, frogs face many threats, such as habitat destruction (because of farming, forestry and urban development); climate change (which is causing exposure to harmful radiation in sunlight); chemical pollution; people using frogs as food or as pets.
Many frog species in South Africa are either endangered or vulnerable especially the Western Leopard Toad is now considered to be endangered. These frogs are found in the Cape Peninsula. Most of its habitat is threatened by the destruction of wetlands and urban development.
Efforts have been made to encourage research, monitoring, fund raising and volunteer work to conserve this frog as well as other frog species of the region.
The Western Leopard Toad Conservation Committee works to create awareness of these threatened species and are involved in conservation, like the removing of alien plants, Eco-friendly gardening and eco-friendly management.
This article first appeared in Supernova Volume 8.3
Words by Antoinette Eyssell – Knox
Illustrations by Benoit Knox and Johann Smith
