Stone Runs, Geography, Falkland Islands

STONE RUNS

The geological phenomenon of stone runs is the most conspicuous element in the Falklands landscape and have facinated and puzzled ever since people first arrived in the islands.

Stonerun-or-witch-large
Witch or which stone run, photo Robert Maddocks

Antoine-Joseph Pernety (Dom Pernety), exploring the Falklands during Bougainville's expedition of 1763/ 64 wrote: 'We were no less astonished at the sight of the infinite number of stones of all sizes thrown one upon another, and yet ranged as if they had been piled negligently to fill up some hollows. We admired with insatiable delight the prodigious works of Nature.' Charles Darwin visiting in 1833/ 34 considered that the 'streams of stones' could have been caused by earthquakes and accurately described them when he said 'they are not thrown together into irregular piles, but are spread out into level sheets or great streams. 'He had crossed a band half a mile wide by jumping from one stone to another and sheltered under a large fragment when overtaken by a shower of rain.

The stone runs form glacier-like streams of hard angular quartzitic boulders and blocks, varying in size from 20 cm to metres long, running down valleys and valley sides. Awesome to look at at ground level, the patterns and stripes are spectacular when viewed from the air. They very well may formed from repeated freezing and thawing processes that began during the last Ice Age 15,000 years ago. Stone runs are greatest on East Falklands, especially on the Wickham Heights where some run for 5km (3.10 miles), including Mount Challenger and the mountains nearer to Stanley, and then there is the huge Prince's Street ( named by Charles Darwin for his hometown and Prince's Street Edinburgh, then cobbled) which runs for around 6.43km (4 miles) between Long Island Mountain and Mount Vernet.

Inland rock includes stone runs and the rocky outcrops on the tops of mountains.
Plants that might be seen growing inand around inland rock and stone runs:
	Lady's Slipper Calceolaria fothergillii	Teaberry 'Malvina Berry' Myrteola nummularia
	Snake Plant Nassauvia serpens	Balsam Bog Bolax gummifera
	Bead Plant Nertera granadenis	Falklands Woolly Ragwort Senecio littoralis
	Falklands Strawberry Rubus geoides	Almond flower Luzruriaga marginata
	Falkland Rock-cress Phlebolobium maclovianum	Silvery buttercup Hamadryas argentea
	Vanilla Daisy Leucheria suaveolens	Falkland Smooth Ragwort Senecio vaginatus
	Pig Vine Gunnera magellanica	Small Fern Blechnum penna-marina
Birds that might be seen in inland rock habitats:
	Red-backed Hawk Buteo polyosoma	Cassin's (Peregrine) Falcon Falco peregrinus cassini
	Crested Caracara 'Carancho' Polyborus p.plancus	Turkey Vulture Cathartes aura
	Falkland Thrush Turdus falcklandii	Dark-faced Ground Tyrant Muscisaxicola macloviana