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Douglas Lake Plateau (BC172)

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Douglas Lake Plateau (BC172)

Kamloops, Colombie-Britannique

Latitude 50,277°N
Longitude 120,303°O
Altitude 625 - 1 000m
Superficie 1 552,33km²

Description du site

The Douglas Lake Plateau extends from the outskirts of Kamloops in the north to Nicola Lake in the south, and to Salmon Lake in the east. The site is a rolling plateau of bunchgrass grasslands, small marshy lakes, Douglas-fir/Ponderosa Pine forest, and aspen parkland. Some portions of the site are improved grasslands or are utilized for agriculture. Most of the hilly plateau is covered with various types of glacial till. All of the lakes that dot the plateau are small except for Nicola Lake, which is significantly larger. The site is also unique for having small populations of Badger, Great Basin Spadefoot Toad (nationally vulnerable) and the Rubber Boa.

Oiseaux

Perhaps the most significant species of the many that use the Douglas Lake Plateau for migration and breeding is the Sandhill Crane (Blue-listed, vulnerable, in British Columbia). More than 10 pairs breed yearly, while over 10,000 birds pass through on both spring and fall migration. These large numbers represent over 1.5% of the North American population of this species. In addition to the cranes, thousands of raptors, shorebirds and mixed waterfowl flocks move through in the spring and fall. This whole site is a major migration corridor for loons, grebes, waterfowl, raptors, shorebirds, gulls and passerines. There is perhaps no other area in the British Columbia Interior that matches the Douglas Plateau in importance for migratory birds.

Two nationally vulnerable species that breed in the dry interior parkland forests are found on the plateau. Possibly the largest concentration of Flammulated Owls in Canada occurs here - some researchers estimate that 600 pairs breed in a large area that goes beyond this IBA. Thus, perhaps 5 to 10% of the poorly known Flammulated Owl population in Canada breed within the IBA. Numbers are additionally difficult to estimate because researchers are not yet sure how numbers of calling birds reflect numbers of paired birds. All three of the habitat subtypes that are required by Flammulated Owls occur here: dry old-growth forest snags (for nesting), grassy or shrubby forage sites, and benches and dry gullies with thickets of vegetation or Douglas-fir groves (for escaping predation). The nationally vulnerable Lewis's Woodpecker also breeds in the area in unknown numbers.

Also present during the summer, are 10 Burrowing Owls that are part of an ongoing Kamloops Wildlife Park release program. This species has been released at several locations within the IBA. Additionally, several raptor species of interest are found here: over 20 Swainson's Hawks breed in the area; at least one Ferruginous Hawk nest site is present that may still be active; and at least 2 pairs of Prairie Falcon.

Provincially uncommon breeding birds, or other birds of interest include: Bobolink, Brewer's Sparrow, Common Nighthawk (August migration), American Avocet, Black Tern, and Yellow-headed Blackbird.

Enjeux de conservation

The plateau is mostly used for livestock rangeland and hence most of the land is owned by large private ranches such as the Douglas Lake Ranch and the Guichon Ranch. Significant areas are also used for intensive farming and there are increasing pressures from housing developments, recreational developments, and the expansion of existing highway corridors. Water management on Nicola Lake has the potential to effect the marshy fringe areas. Although deforestation and tree cutting are occurring in local areas, the most threatened ecosystem in the site would be the natural grasslands.

This is a very large, complex area that presents significant challenges in terms of developing management strategies. At present, Ducks Unlimited has been involved in several projects within this area, most notably at Beaver Ranch Flats and Stumplake Creek. On Guichons Ranch there is a wildlife viewing location established by Ducks Unlimited.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
Grue du Canada
Nombre Année Saison
10 0001995Automne
10 0001995Printemps
Pic de Lewis
Nombre Année Saison
16 - 202016Automne
102016Été
122015Automne
?1995Été
Chevêche des terriers
Nombre Année Saison
101995Été