Where fog occurs, flora and fauna survive in surprising abundance. The Namib desert boasts abundant lichen fields sustained by over ninety days of coastal fog a year. Fog supplies up to 40% of the coastal precipitation, the rest comes from the mere 9mm average rainfall.
Lichens are best seen on the last days of our Damara Elephant and Namib Desert Safaris as we traverse the coastal plains. Although, to the casual observer, these gravel plains appear devoid of life, but bend down close to the ground and you will see some of the more than 100 lichen species - many endemic to the Namib.
Image right: White quartz pebbles sporting jet-black and rust-coloured lichens typical on coastal plans
Lichens are not really plants at all but rather a symbiotic relationship (living together) between an algae and a fungus. While the algae is the dominant partner, changing sunlight into nutrients via chlorophyll, the fungi forms the largest part of the relationship. The fungi provides an anchor to rocks and stones as well as absorbing minerals from the earth and rocks to feed the algae.
Lichens augment the ecosystem of the desert pavement by stabilising the upper layers of soil also providing food for a variety of invertebrates - even springbok in dry times. It is estimated that some of these lichen could be hundreds, even thousands of years old as they are capable of surviving years of drought. Sadly they are easily disturbed and die from the least disturbance, especially off-road driving - one pass by a 4x4 vehicle destroys the lichen completely. Growth rates are exceedingly slow - about 1mm a year.
Lichens grow on the western side of shrubs, rocks and even on quartz pebbles. Best seen in bright colours on foggy mornings - in the afternoon they appear dry and dead, but sprinkle some water on them, and a miracle occurs as they unfurl into life. Image: intricately branched Namib lichens almost resemble corals, whilst others look like dried leaves.
Image right: Fog condenses on stones causing a veritable miniature oasis for plants including a patch of almost while lichen