Natures Valley Guano Cave
Natures Valley Guano Cave, (105m long, 28m high)
At the eastern end of the Nature’s Valley beach is a rocky headland
marked as Die Punt (The Point) on the 1:50 000 topographical
map.1 The surface of the Point consists of highly brittle,
shattered quartzite, covered in low shrub, and topped by coastal fynbos.
The Groot River Guano Cave is situated in this headland.
Description
The cave entrance faces south, towards the Indian Ocean, and is
approximately 10m wide by 28m high. Although quite large, the entrance
cannot be seen from the Nature’s Valley beach, as it is on the eastern
side of the point. This entrance is common to both levels of the cave.
The lower level is just above the current high tide mark, and is narrow
and approximately 20m long. This passage was filled with debris and
dried seaweed brought in by the sea. The main passage is 15m higher, and
runs straight into the cave for 56m before splitting into two passages.
The western passage is low, and wide, and the smooth walls and ceiling
indicate that the cave was formed by water action. The eastern fork is
higher, narrower and longer, but ends after about 35m in a narrow crack.
About 12m from the main entrance, a short passage leads to a much
smaller side entrance. This entrance offers relatively easy access to
the cave, and rewards the explorer with spectacular views of the
Nature’s Valley beach.
The floor of the main passage is relatively level, but in one section,
has a few scalloped holes in it, very similar to the scallops found on
the seaward edge of the Blue Rocks at the western end of Nature’s
Valley. There are also some large boulders scattered towards the back of
the cave.
Fauna
This cave is mentioned in a foresters report2 from the 1920s
as a possible source of bat guano, and Kingston, an archeologist,
visited the cave in 1901 and reported that farmers extracting guano had
already disturbed the archaeological deposits. 3 When we
visited the cave there was not much sign of bat guano. There were
however small quantities of dassie droppings. The only other guano in
the area is on the rocky point itself. This point is used as a roost by
cormorants, and it is covered in bird guano.
The cave is probably used as a shelter by bats moving along the coast,
but the main inhabitants are currently rock pigeons and swifts. We did
not make a thorough search for invertebrates.