Amphibians
Table Mountain Ghost Frog
Heleophryne rosei · also called table mountain ghost frog, rose's ghost frog
The Table Mountain ghost frog lives in one of the smallest ranges of any frog on Earth: a scatter of fast, clear streams on the slopes of Table Mountain, right above the city of Cape Town. It is a flattened, purple-blotched rock climber, hauling itself up wet vertical stone on sticky-tipped toes, and its tadpoles cling to boulders in the current with a sucker mouth.
Overview
The Table Mountain ghost frog is confined to perennial streams on the eastern and southern slopes of Table Mountain, an area of only a few square kilometres. It is 5–6 cm long, green with purple to reddish-brown blotches, with large eyes, huge webbed hind feet, and broad adhesive discs on its toes.
A rock climber
The flat body, strong limbs, and toe discs let it cling to and move across smooth wet rock, including near-vertical faces beside waterfalls, and wedge into damp cracks.
Torrent tadpoles
The tadpole has a large sucker-like mouth that grips rock against the current while it grazes algae off the stone. The tadpole stage lasts about a year, so the frog needs streams that flow all year round.
Why “ghost”?
The name is variously tied to Skeleton Gorge, one of its ravines, to the frog’s pale look in torchlight, and to its habit of vanishing into crevices. Its true origin is unclear.
Status
The Table Mountain ghost frog is Critically Endangered, with perhaps only a few thousand adults. Reservoirs, invasive pines and wattles, too-frequent fire, erosion, and heavy recreational use all reduce or foul its streams. Its range lies inside Table Mountain National Park, and conservation focuses on restoring stream flow and limiting disturbance.
Table Mountain Ghost Frog: common questions
Why does the Table Mountain ghost frog have such a small range?
It is a specialist of clear, cool, fast-flowing perennial mountain streams with rocky beds, and on Table Mountain that habitat exists only in a few ravines on the wetter southern and eastern flanks. The frog needs these streams year-round because its tadpoles take about a year to develop and must have flowing water the whole time. It cannot survive in slow, warm, or seasonal water, and it cannot cross the dry, developed, or built-up land between catchments. As a result the entire global population is packed into a strip of mountain only a few kilometres across, essentially within sight of central Cape Town.
How do the tadpoles survive in fast-flowing water?
They are built to hold on. A ghost frog tadpole has an enlarged, flattened mouth on the underside of the head that works as a sucker, letting it clamp onto smooth rock in the current so it is not washed downstream. Anchored in place, it scrapes a living from the film of algae and diatoms growing on the stone. The body is streamlined and muscular for the occasional dash between holds. This lifestyle ties the tadpole absolutely to permanently flowing, well-oxygenated streams, which is one reason changes to water flow on the mountain are so damaging to the species.
Is the Table Mountain ghost frog dangerous or venomous?
No. It is a small, harmless, secretive frog that poses no threat to people. It is difficult even to see, being nocturnal, well camouflaged against lichen-covered rock, and quick to disappear into a crevice or under a boulder when a light is shone on it. Most residents of Cape Town have never encountered one despite living beside its habitat. The concern with this species runs entirely the other way, in that human activity on and around the mountain is the reason it is Critically Endangered.
What is being done to conserve it?
Almost all of the frog's range lies within Table Mountain National Park, so the habitat has formal protection, and management focuses on the specific threats — clearing invasive pine and wattle to restore stream flow and fynbos, managing fire so it is not too frequent, controlling erosion and sedimentation, limiting disturbance from hikers and from infrastructure near the streams, and monitoring the population. Because the range is so tiny, there has also been discussion of maintaining a captive assurance population, but breeding a stream-adapted frog with a year-long torrent tadpole is technically difficult.