Chopaka Customs (BC260)

Chopaka Customs (BC260)

Osoyoos, Colombie-Britannique

Description du site

Chopaka Customs IBA is situated in southern British Columbia and encompasses a small area of land adjacent to the Canada-USA border immediately north of Nighthawk, Washington State. The site, located along Nighthawk Road, is comprised of rolling hillsides with cliff outcrops at higher elevations, along with shrub-steppe vegetation dominated by big sagebrush and indigenous bunchgrasses. The climate is semi-arid and there is no permanent water on site. Soils are shallow and rocky on the predominantly sloped terrain, being deeper and more loamy on the flats. Other fauna with restricted distributions in British Columbia which occur at this site include Western Rattlesnake, Gopher Snake, Racer, Western Harvest Mouse, Great Basin Pocket Mouse and American Badger. The White-tailed Jackrabbit, likely now extirpated from British Columbia, was last reported from this site in July 1981.

Oiseaux

Significant Species - The Chopaka Customs IBA supports nationally significant populations of Sage Thrasher and Lewis's Woodpecker, considered Endangered and Threatened, respectively, 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). Up to six pairs of Lewis's Woodpecker are known to breed annually here, and this is one of the few places in British Columbia that supports regularly breeding Sage Thrashers (minimum of 1-2 pairs/year).

Other Species of Conservation Interest - Threatened (COSEWIC) Common Nighthawks occur within the IBA and likely still breed there. Threatened Barn Owls and Special Concern Long-billed Curlews (COSEWIC) are known to occur within the IBA and in agricultural lands adjacent to the site. Notable populations provincially rare (red-listed) Brewer's and Lark Sparrows breed at the site and the provincially rare (red-listed) Grasshopper Sparrow occurs here occasionally. Endangered (COSEWIC) Western Screech-owls (macfarlanei subspecies; interior population) can be found regularly in the southwestern corner of the IBA.

Enjeux de conservation

Loss or alteration of habitat is the key pressure for Lewis's Woodpecker, Sage Thrasher, and other species at Chopaka Customs. A vineyard was recently established in the northeast section of the IBA in an area known to support breeding Brewer's Sparrow and Common Nighthawk. Intensive grazing can impact sagebrush habitat and much of the land within the IBA is grazed. During September 2011 a wild fire burned some of the land within the southwestern corner of the IBA. The fire impacted minimal sagebrush, and likely improved habitat for Lewis's Woodpecker. Brushing of large sagebrush along the side of the road could destroy nesting habitat for Sage Thrasher. Invasive or introduced plants like cheatgrass, Russian knapweed and diffuse knapweed have altered the grasslands. Portions of the IBA were mowed and seeded with crested wheatgrass in the late 1970s and the area has never properly recovered. Competition with European Starlings for nest cavities may be becoming more of a threat to Lewis's Woodpeckers in this region (COSEWIC 2010a). Horse riding is a frequent activity at the site, with hiking and birding occurring but less frequently. Recreational activities have the potential to disturb breeding birds, spread invasive plants 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. Most of this IBA is within the South Okanagan Grasslands Protected Area. The Land Conservancy (TLC) purchased a property along the Similkameen River for conservation purposes. Several private properties along the Similkameen River are TLC Conservation Partners. Two Wildlife Habitat Areas (WHA's) have been established for Sage Thrasher and eight for Lewis's Woodpecker. A further four are proposed for Brewer's Sparrow with measures that aim to limit the impact of livestock grazing to WHA values. Efforts are ongoing to control invasive Russian knapweed. Some disturbed areas within the Protected Area boundary could be restored with native vegetation, although cattle grazing each spring may limit the success of any restoration efforts. An IBA sign was installed in 2011 and tours of the IBA have occurred during the Meadowlark Festival. Formal and informal bird surveys occur within the IBA; these surveys should continue and expand to other species of conservation concern.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection

• Moqueur des armoises10 (max.)
• Pic de Lewis12 (max.)
• Ictérie polyglotte1 (max.)
• Grue du Canada5 000 (max.)