Vlêrmuis Grotte, Die Hel, Groot Winterhoek

Peter Swart, 1996

Location

Die Hel is a large pool (approx 60m by 80m by 11m deep) on the Groot Kliphuis River in the Groot Winterhoek wilderness area. All directions are given starting at the point where the path comes down to the river.

There are three known caves around the pool. On the western side of the pool is large cave entrance, which is most easily reached by swimming across the pool. The cave is very easy to find. Not only is the mouth of the cave easy to spot (approx 9m across by 6m high), but it is also easy to smell. Just swim to the middle of the pool, and follow the aroma of the bat guano. On the eastern side of the pool, are two caves which can be reached by climbing over the boulders between the water and the cliff. Cave B is the southern most cave and Cave C the northern most. All of the caves are formed in the steep, red, quartzitic sandstone cliffs of the gorge through which the Groot Kliphuis River flows.

Caves

Cave A, Vlêrmuis Grot

This is the largest of the caves and is home a fruit bat roost.

Cave B

This cave is set back behind some trees, and is a seasonal nursery roast for horseshoe bats and bent wing bats.

Cave C

This cave has an entrance open to the large pool, and chambers higher up the slope. There was a roost of bent wing, and what looked like Myotis bats in the semi darkness of the pool passage.

Biology

Many invertabrates were collected from from the cave, although none have yet been identified.

A group of well over a hundred bats was found in the eastern chamber, and a number of Horseshoe bats, some of which were carrying babies, were found in the network section. A ghost frog was also found in the twilight zone of the network section of the cave.

(1) Although no analysis of these formation has been done, they appear as small stalactites, and appear to have formed from amorphous silica.

Species collected:
* Invertabrates - not yet known

Bats:
* Rhinolophus capensis (Cape Horseshoe bat)
* Rhinolophus clivosus (Geoffory's Horseshoe bat)
* Miniopterus spp (two species)
* Rousettus aegyptiacus leachii (Cape fruit bat??) (not confirmed)

Frogs:
* A ghost frog was observed in the twilight zone of Cave C.