Deserts are hot, dry places with less than 25 cm of rainfall per year where evaporation exceeds precipitation. They are inhabited by plants and animals that have evolved to survive these harsh conditions.
Canada’s best-known desert is located in the area around Osoyoos, British Columbia. While it has more rain than is standard for a desert, it certainly has the fauna and flora. A narrow strip around Ashcroft, just over 300 km north of Osoyoos, is technically better qualified as it receives less rainfall.
The governments of Canada and British Columbia and the syilx/Okanagan Nation have signed a memorandum of agreement to establish a national park reserve in the South Okanagan-Similkameen to protect 273 square kilometres, including the South Okanagan Grasslands Protected Area, between Oliver and Osoyoos. Establishing a national park will provide additional resources to protect rare pockets of semi-arid desert and species at risk such as American badgers, flammulated owls, yellow breasted chat, desert night snakes, and western rattlesnakes.
The Nature Trust of BC is protecting a 152-hectare Antelope-brush conservation area. Antelope-brush is only found in the southern portions of the Okanagan Valley and the Rocky Mountain Trench. It “thrives in soil derived from windblown sand and the sands and gravels deposited by the meltwaters of the Ice Age glaciers’, growing long tap roots to reach moisture. Its yellow flowers provide pollen and nectar for many insects and the plants are a nutritious source of food for Mule Deer and California Bighorn Sheep.” Many creatures build nests and shelter in the shade of antelope-brush.
Here are 3 places to visit and learn more about BC’s desert country.
South Okanagan Grasslands Protected Area
The South Okanagan Grasslands Protected Area consists of four sites: Mt. Kobau, Kilpoola, Chopaka East and Chopaka West. The Protected Area consists of dry grasslands and open forests, one of the most endangered landscapes world-wide. There are opportunities for hiking and a lookout on top of Mt. Kobau provides a view over Okanagan Valley, Osoyoos Lake and the Similkameen Valley. The lookout is considered to be one of the best places in Canada for astronomy with an annual Star Party for keen amateur enthusiasts.
The Protected Area is home to 4 rare plants as well as a number of lichens that grow on the ground, including several species new to science. Dry ground and terrestrial lichens are cryptogams, a group of plant-like organisms that reproduce by spores rather than flowers or seeds. They can play an important role in hot, dry ecosystems by covering and stabilizing the soil, capturing nitrogen from the air, and providing nutrients for plant growth.
Osoyoos Desert Centre
The Osoyoos Desert Centre is a volunteer organization that strives to generate public knowledge, respect, and active concern for the South Okanagan’s fragile, endangered antelope-brush ecosystem. The 67-acre nature centre, located 3 km north of Osoyoos, is open from May through to early October with restricted hours earlier in the spring. Visitors can learn about desert ecology, habitat restoration, and conservation by taking a guided/self-guided tour of the 1.5 km raised boardwalk, visiting the native plant demonstration garden, as well as touring the exhibits in the interpretive building. School and group tours are available.
The Centre has undertaken a number of initiatives to conserve and restore native habitat and species. Two ponds have been created as breeding habitat for Great Basin Spadefoot toads that are only found in south-central BC. Antelope-brush, nectar plants, and grasses have been planted near the boardwalk entrance to provide a supportive environment for Behr’s Hairstreak butterflies that only lay their eggs on antelope-brush. Invasive weeds have been removed and native grasses, flowers, and shrubs replanted.
NK’MIP Desert Cultural Centre
The NK’MIP Desert Cultural Centre is a 50-acre desert conservation centre established by the Osoyoos Indian Band. It includes both indoor and outdoor cultural and nature exhibits. The building is semi-underground to take advantage of the land’s insulating property and the walls are built using ancient rammed-earth techniques. Hot water circulates under the floors to heat the building in winter and cold water circulates through ceiling pipes to cool it during the summer.
There are 2 kilometres of walking trails through antelope-brush and sage desert, Ponderosa Pine forest, rugged hills, and shady creek habitats. The trails lead to a traditional village and exhibits introduce the culture of the Okanagan First Nations and how they used plants as food, medicine, and technology. Get a bird’s-eye view of the desert by rappelling down a cliff.
Research is being carried out on the site into Western Rattlesnake and Great Basin Gopher Snake. The Western Rattlesnake is one of BC’s largest snakes with a broad, triangle-shaped head, a light brown back overlaid with dark brown blotches, a yellowish-white belly, and a rattle at the end of its tail. They hibernate in communal dens. In summer, they follow regular paths to foraging and basking sites a kilometre or more from the den. The Great Basin Gopher Snake squeezes rodents and juvenile birds to death before eating them. They maintain large home ranges (5-25 hectares) so that they can find suitable food resources and egg-laying sites.
British Columbia’s Grassland Regions (listing grassland landscape, unique features, plants, wildlife, and species at risk for each of 8 grassland ecosystems)
Antelope-Brush Ecosystems, Province of British Columbia
Nature Companion, a free app/website introducing many of the plants and animals found in Canada’s four western provinces
Photo credit: https://www.flickr.com/photos/apmckinlay/19061085166/