Sparsely Vegetated Ecosystems (SV)
In the Discovery Islands
• Sparsely vegetated ecosystems occur on rocky outcrops, cliffs, talus-boulder slopes or expanses of sand or gravel with thin soil pockets that become moisture-deficient due to rapid drainage and the drying effects of exposure to sun and wind.
• Sparsely vegetated ecosystems have 5-10% low patchy vegetation of small herbaceous plants, mosses, liverworts and lichens; occasional microsites, such as rock crevices with sufficient soil, will support a hardy shrub or tree.
• They include rocky cliff ledges and fissures providing protected habitat for birds, bats, snakes and lizards.
DIEM has mapped Sparsely Vegetated Ecosystems grey blue in the Sensitive Ecosystems Mapping.
Cliffs, rock outcrops, and slabs of exposed bedrock—both coastal and inland—are classified as sparsely vegetated ecosystems due to their very limited patchy soils and flora. In the Discovery Islands, this ecosystem type predominates along many shorelines, where substrates also include talus-boulder slopes and shoreline spits of sand or gravel. Cliffs also occur inland where erosion has carved steep bluffs in the landscape. Here, as on the lower rocky outcrops, soils are usually skeletal and moisture-deficient due to limited inflow of freshwater, rapid drainage and drying, and vegetation is mostly patches of mosses, liverworts and lichens tucked into sheltered depressions.
Sparsely vegetated ecosystems are challenging environments where plants are slow to establish and easily disturbed. These rocky places are fragile habitat with less than 10% coverage of low vegetation; however, where conditions permit, they support a few wildflowers and even the odd shrub or hardy tree. Ledges and fissures in cliff areas also offer isolated habitat, generally providing protection from predators and they are choice nesting sites for a variety of birds. Steep parts of sparsely vegetated ecosystems provide valuable protected habitat for many small animals, including rare species. Crevices are used by roosting bats and also serve as shelter and overwintering areas for snakes and lizards.
WHEN YOU EXPLORE sparsely vegetated ecosystems, do your best to prevent disturbance and noise, especially during nesting season from March to August.
Look For Typical & Rare Species in Sparsely Vegetated Ecosystems
NOTE: Sparsely vegetated and herbaceous ecosystems have many species in common.
FLORA Arbutus, blue-eyed Mary, camas (death & common blue), coastal strawberry, common juniper, dune-grass, fragile fern goldenback fern, Hooker’s onion, ladies tresses, lichen species, monkey flower, many-flowered wood-rush, nodding onion, parsley fern, rock mosses, sea blush, sedum, smooth alumroot, yarrow, yellow sand verbena.
FAUNA Alligator lizard, anise swallowtail butterfly, belted kingfisher, black bear, black-tailed deer, cougar, glaucous-winged gull, northern rough-winged swallow, killdeer, little brown bat, pelagic (& /or double-crest) cormorants, peregrine falcon, savannah sparrow, turkey vulture.
SPECIES AT RISK Smooth willowherb (Blue), Queen Charlotte avens (Red), hoary brome (Red), Douglas’ sagewort (Red), peregrine falcon (Blue, Special Concern), Keen’s long-eared myotis (Blue), Townsend’s big-eared bat (Blue)
* For comprehensive species lists & rarity explanation, click here.
Some Local Sparsely Vegetated Ecosystems
In the Discovery Islands, Sparsely Vegetated ecosystems are found along large portions of the shoreline of most islands, except for Marina Island. At the shoreline the intertidal rocky cliffs and out crops often continue on to the land. Some Sparsely Vegetated cliff ecosystems may be currently mapped as herbaceous but will be appropriately described as they are ground-truthed by DIEM participants. The talus slopes on the heights of East Redonda and Sonora islands have not been evaluated.
Familiar Locations Sonora Island: Hole in the Wall, Cortes Island: Gorge Harbour entrance, Quadra Island: Blind Man’s Bluff, Read Island: Sheer Point Cliff, Maurelle Island: Elephant Mountain