Just bare gravel? Not quite
24th December 2007, MondayDungeness and Rye Harbour support internationally important areas of shingle vegetation. Yet when you look at these sites there is a lot of bare gravel and its tempting to assume it is of no botanical value. Take a close look however, and a different picture emerges, for despite its lifeless appearance the gravel is actually vegetated. Where the flints have been allowed to lie undisturbed for some time they are home to a range of encrusting lichens like the black specimens below.
Sometimes at first sight it appears that the gravel has been splashed by a careless painter.
These strips of pebbles are a natural feature of Dungeness - the sea sorts the gravel into bands of fine “pea beach”, that are easily colonised by higher plants, and coarser stones which are too inhospitable a habitat for most plants other than these lichens. The northern edges of the shingle beaches at Dungeness are frequently dominated by this exposed gravel. Its tempting to regard them as damaged, but once again the action of the sea is reponsible. As you travel north from Dungeness Point towards the appropriately named Greatstone the diameter of the flints increases and therefore larger expanses of coarse gravel, vegetated mainly by encrusting lichens, are the natural state of these parts of the beach.
The lichens can be a warning sign to nature reserve managers trying to determine if these fragile sites are being damaged by people. Vehicle-use on shingle is really bad news, and if repeated can destroy the vegetation, for decades on the older areas of shingle. On a large shingle beach localised damage can be hard to spot were it not for the lichens. They change the colour of the gravel. If parts of the site are being subject to disturbance by vehicles, which upturn the flints, they show up as a different colour. Consequently new tracks across the gravel are very easy to spot. Despite their small size these plants take many years to grow so the damage will show up for many years.
They are not the most obvious of species, however the extent of the gravel at these sites and the range of lichens growing on them make our shingle beaches one of the better places in Britain to study coastal lichens.