Chopaka East and Kilpoola Lake Area (BC169)

Chopaka East and Kilpoola Lake Area (BC169)

Osoyoos, Colombie-Britannique

Description du site

The Kilpoola Lake area is located in rolling hills about 5 km west of Osoyoos, extending from the Canada-United States of America border north about 5 km to Blue Lake. The site itself is a mix of open bunchgrass grasslands (primarily big sagebrush), aspen copses, and open, dry coniferous woodlands dominated by Douglas-fir with scattered Ponderosa Pine. Kilpoola Lake, an alkaline lake about 20 ha in size is part of this IBA, as are several small ponds. This diversity of habitats in the area creates a situation of high avian diversity, and makes this site a favourite among BC birdwatchers. The site hosts many rare or endemic species of fauna and flora, such as Merriam's Shrew and Lyall's Mariposa Lily, which occur nowhere else in Canada. It is also prime habitat for many mammals, including Spotted Bat and Nuttall's Cottontail, and amphibians, such as Great Basin Spadefoot and Tiger Salamander.

Oiseaux

Significant Species - Kilpoola Lake Area supports nationally significant populations of Lewis's Woodpecker and Sage Thrasher. Lewis's Woodpecker, determined to be Threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC; wildlife species that have been assessed as at risk by COSEWIC may qualify for legal protection and recovery under Canada's Species at Risk Act) regularly breed here; up to 10 breeding pairs have been detected annually in recent years. Small numbers of Sage Thrasher, listed as Endangered by COSEWIC, have been recorded in the IBA since 2001 with a minimum of five singing males and one female observed in 2008.

Other Species of Conservation Interest - Small numbers of Special Concern (COSEWIC) Flammulated Owls breed near Blue Lake. Threatened (COSEWIC) Common Nighthawks have been detected and likely breed in the IBA annually. The nationally endangered Sage Grouse formerly occurred here, but has since been extirpated. Endangered (COSEWIC) Burrowing Owls have recently been reintroduced to the area but were not yet established as of 2013. Provincially rare (red-listed) Brewer's, Grasshopper, and Lark Sparrows also occur at the site.

Enjeux de conservation

Loss or alteration of habitat is the key pressure for Lewis's Woodpecker, Sage Thrasher, and other species at risk in the Kilpoola Lake Area. Sagebrush habitat utilized by Sage Thrasher and Lewis's Woodpecker is impacted by grazing and at risk of being destroyed by catastrophic fires (COSEWIC 2011). Invasive or introduced plants like sulphur cinquefoil, cheatgrass, Japanese brome, diffuse knapweed, Russian knapweed, Dalmatian toadflax and crested wheatgrass have altered the grasslands. Cheatgrass in particular increases fine fuels and the risk of fire. Logging on private lands in the area has removed most of the large old trees essential for Flammulated Owls. Removal of dead and dying trees for firewood, human-safety, aesthetic, or other reasons could impact Lewis's Woodpecker and other cavity nesters (COSEWIC 2010a, COSEWIC 2008). Competition with European Starlings for nest cavities may be becoming more of a threat to Lewis's Woodpeckers in this area (COSEWIC 2010a). Recreational activities have the potential to disturb breeding birds and cause degradation and erosion of sensitive grassland habitat.

Sage Thrasher and Lewis's Woodpecker are listed under Canada's Species at Risk Act; as such, species specific recovery strategies are drafted to identify critical habitats and unique conservation needs etc. A large amount of the IBA is protected within the provincial South Okanagan Grasslands Protected Area, which was established in 2001 a result of the Okanagan-Shuswap Land and Resource Management Plan. The Province of British Columbia has also designated eight Wildlife Habitat Areas (WHA) for Lewis's Woodpecker and one for Sage Thrasher. The Nature Trust of British Columbia owns a small parcel at Kilpoola Lake. The Nature Conservancy of Canada recently purchased several large parcels in the IBA. Most of the remaining area is privately owned.

A variety of conservation activities are underway at the site. In 2013, Nature Conservancy of Canada completed a property management plan and a preliminary invasive plant inventory with a plan for subsequent control measures. Species at risk are regularly inventoried on conservation lands. Grazing is excluded on some conservation properties. Burrowing Owls are being reintroduced within the IBA. Interpretive signs have been installed at Blue Lake and along the access to Sagebrush Slopes, where gates have been installed to prevent motorized access without permission. Fencing of riparian habitat on conservation lands to exclude cows is planned for 2014.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection

• Moqueur des armoises9 (max.)
• Pic à tête blanche2 (max.)
• Pic de Lewis20 (max.)