Rocky Talus Slopes/ Rock Outcrop

Click on each section to find out about species found in Rocky Talus Slopes/Rock Outcrops

These rocky, dry communities are found throughout the grasslands at all elevations and provide important habitat features for many creatures. In places where their steep slopes face towards the sun the rocks absorb heat during the day and stay warm through the night, creating a special, warmer area for cold-blooded animals such as snakes, insects, and scorpions.

Vegetation in these dry areas is patchy and usually sparse. Low, gray-green mats of compact selaginella cover places where there is a thin layer of soil over the rock. A member of the Spikemoss Family, compact selaginella spreads by long trailing stems. Grasses are much less abundant and the plants are smaller and less vigorous in these dry areas. Common plants include scattered big sageb, pasture sage, and rabbitbrush. Rain often cascades over rocky features, concentrating moisture at the base, where plants that require more moisture thrive.

Mock-orange, smooth sumac and saskatoon are characteristic of Okanagan and Kootenay valley cliffs in moist hollows. Rocky Mountain juniper and common juniper are common shrubs in Thompson basin while creeping juniper occurs with them in the lower areas of the Chilcotin and on the small grassy openings on south-facing slopes of the Stikine, Dease, Liard, Kechika and Peace River valleys of northern BC. On Southern Vancouver Island and the Gulf Islands, scrubby oaks, licorice fern and rock mosses are characteristic of the rocky habitats in Garry oak grasslands.

Rock features provide important habitat for many animals. Spaces between the rocks provide shelter to raise young, hibernate, or escape from predators. Rock crevices are used by many species of bats as roosting sites during the summer; Little Brown Myotis, Western Small-footed Myotis, Big Brown Bat and Townsend’s Big-eared Bat are known to hibernate in caves and abandoned mine shafts in the lower elevations of the Fraser, Thompson and Okanagan valleys.

Many bird species use cliff ledges to build their nests. Tell-tale white markings on the cliffs below nest sites can often be seen from quite a distance. Rock outcrops are often used as loafing areas to absorb the heat from the sun, or as lookout points to watch for predators. Yellow-bellied Marmots, Western Pine Chipmunks, Western Skinks, and Rock Wrens all use these vantage points. California Bighorn Sheep use rocky slopes to escape from predators, especially in spring when they give birth to their young.

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Photos:
Kristi Iverson (talus slope)

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