IBA South Okanagan including Hayne’s Lease

Posted February 12, 2006 | Categories : 100,Reports,Research,Species List |


IBA Osoyoos Oxbows
South Okanagan Valley, British Columbia
Site Summary
BC261 Latitude
49.096° N
119.539° W
280 – 500 m
14.27 km²
deciduous woods (temperate), native grassland, rivers/streams, freshwater marsh
Land Use:
Agriculture, Nature conservation and research, Hunting, Rangeland/pastureland, Tourism/recreation, Water management
Potential or ongoing Threats:
Arable farming, Dredging/canalization, Introduced species, Recreation/tourism, Urban/industrial development
IBA Criteria: Nationally Significant: Threatened Species
Conservation status: Ducks Unlimited Canada (owned by), Ecological Reserve (provincial), IBA Conservation Plan written/being written, Nature Conservancy (owned by), Nature Trust of British Columbia, Wildlife Management Area

The Osoyoos Oxbows are located in the South Okanagan Valley in south central British Columbia. The oxbows wind along both sides of the Okanagan River channel from the north end of Osoyoos Lake to Road 18, Oliver. Most of the site lies along the Okanagan River channel, a canal-like structure with gravel dykes. The old river channel winds back and forth across the flat floodplain, which is about 1 km wide. Water birch woodlands line the oxbows, while a cattail-bulrush marsh lies east of the river mouth where it empties into Osoyoos Lake. This marsh once extended to the west side as well, but has largely been drained or filled on that side. Arid, sandy bench-lands lie directly to the east of the floodplain, extending at one spot to an outlying rock bluff with associated talus.


The Osoyoos Oxbows support one of the most significant populations of Yellow-breasted Chats in British Columbia. This population is designated as nationally Endangered. In 1999, at least 8 birds were recorded, which represents about 8% of today’s population. Five other nationally at risk species are present at this site: Barn Owl (2 individuals; Threatened species), Long-billed Curlew (4 individuals; Special Concern species), Bobolink (50 individuals; Threatened species), Western Screech Owl (2 individuals; interior population nationally Endangered species), and Lewis’s Woodpecker (4 individuals; Threatened species). Burrowing Owls (nationally Endangered) were formerly present at this site. Other noteworthy species found here include Prairie Falcon (2), Lark Sparrow (40), and Grasshopper Sparrow (5).The marshes at the north end of Osoyoos Lake represent one of the last remnants of a once significant chain of wetlands found in the valley bottom of the Okanagan. These wetlands harbored species such as American Bittern, Northern Harrier, Virginia Rail, and Yellow-headed Blackbird. The easy access along Highway 97 and the high diversity of birds and habitats makes the Osoyoos Oxbows one of the premier birding sites in Canada. After Vaseux Lake (about 20 km to the north), it has the best cross-valley connectivity of natural habitats in the Okanagan Valley.

Summary of bird records available for Osoyoos Oxbows
Click here to view all records
Species Season Number Unit Date
Barn Owl BR 2 I 1995
Bobolink BR 50 I 1999
Burrowing Owl BR 2 I 1985
Grasshopper Sparrow BR 5 I 1999
Lark Sparrow BR 40 I 1999
Lewis’s Woodpecker BR 4 I 1995
Long-billed Curlew BR 4 I 1995
Prairie Falcon BR 2 I 1995
Western Screech-Owl RE 2 I 1995
Yellow-breasted Chat (Okanagan) BR 8 N I 1999
Note: species shown in bold indicate that their population level (as estimated by the maximum number) exceeds at least one of the IBA thresholds (national, continental or global). The site may still not qualify for that level of IBA if the maximum number reflects an exceptional or historical occurence.
Conservation Issues

The west side of the area, particularly south of Road 22, has been altered by attempts to drain and fill the wetlands in order to sell 10-acre lots on the site. Elsewhere, clearing of riparian woodland has taken place to maximize pasture production. Some of the IBA is included within the South Okanagan Wildlife Management Area and Haynes Lease Ecological Reserve. In addition, three conservation organizations (the Nature Conservancy of Canada, The Nature Trust of British Columbia and Ducks Unlimited Canada) own and manage land in this IBA to benefit wildlife. Some parts of the riparian woodlands have been fenced to exclude cattle, and a major re-flooding project to restore some water flow to the marshes and oxbows was undertaken by the British Columbia Wildlife Branch and Ducks Unlimited.