What are oxbows?
Essentially a cut-off river bend (meander), an oxbow is a crescent-shaped lake or pond lying alongside a winding river. It can be wet or dry. The oxbow lake is created from the meanders of a river over the course of many years, as erosion and deposits of soil change the river's course, eventually cutting off the ‘loop’ of the meander.
Where can I find them?
What are generally known as the ‘Osoyoos oxbows’ lie at the north end of the lake between Road 18 and Road 22. They were formed when the Okanagan River was straightened and channelised in the 1950’s for flood control purposes. Some are on private property while others form part of a Fish & Wildlife Reserve. Other oxbows can be found further north, along the old meanders of the river between Road 18 and Penticton.
What’s so special about them?
The oxbows form one of the few remaining wetlands in Osoyoos.
They are biologically very productive, providing shelter to a huge variety of both land, air and water-based species right across the food chain. Each species is crucially linked with all the others, forming a thriving yet extremely fragile ecosystem – rather like a tropical jungle. Think of a game of Jack Straws ….. remove or damage even one tiny part of it, and the entire balance in the chain of life is upset. The Osoyoos oxbows are unusual in that they are home to many rare or threatened species of birds, amphibians and insects such as the Yellow-breasted Chat, the Great Basin Spadefoot Toad, and the painted turtle.
The actual area is very small, and growing smaller each year due to human encroachment. Because of this the unusually wide variety of species that use it, both as a home and as a migratory resting place, is considered by biologists to be at risk.
The oxbows form part of a narrow and highly important ‘wildlife’corridor for migrating birds.
They are an important and scientifically-recognised birdwatching area, attracting eco-tourists and birders from all over the world.
What’s being done to protect them?
After the establishment of the Fish & Wildlife preserve in the early 1980’s, parts of the riparian woodlands were fenced to exclude cattle. In addition, Ducks Unlimited and the Ministry of Environment worked together on a major re-flooding project to restore some water flow to the marshes and oxbows in 1983. Other initiatives have included weed control and the installation of interpretative signs. An active riparian stewardship program, initiated in 1997 by the Ministry of Environment known as the Riparian Restoration of Oxbows in the South Okanagan, has worked with interested landowners primarily outside the bounds of the Wildlife Area.
Osoyoos Oxbows Restoration Society
The Osoyoos Oxbows Restoration Society was formed in 2004 to assist in the rehabilitation and enhancement of the natural oxbows of the Okanagan River north of Osoyoos Lake. A healthy restored flowing Okanagan River and riparian ecosystem will help to resolve many of the problems these activities created over the past decades. By allowing water to flow once again into the old river meanders and cut off oxbows they hope to achieve the following:
* reduce sedimentation and water turbidity,
* provide water storage and reduction of floods,
* recharge our ground water levels,
* aid in erosion control and prevent/mitigate siltation,
* increase dissolved oxygen supply and moderate seasonal water temperature,
* digest pathogens and contaminants,
* allow them to act as nutrient assimilators (especially for nitrates and phosphates),
* eliminate mosquito breeding grounds and reduce the possibilities of water borne disease incidents.
Additionally, the habitat for waterfowl, fish and other wildlife would be enhanced and recreational opportunities for residents and tourists would be increased.
A feasibility study is underway at present (January 2007), as are fundraising efforts and public awareness campaigns.
The Osoyoos Oxbows Society is working with the Osoyoos Lake Water Quality Society, Ducks Unlimited and other groups plus all three levels of government to reach these goals.
Update - February 2007
Seventy acres of private land that forms part of the Osoyoos oxbows/wetlands has been sold to a developer. No plans have been finalised as to the actual nature of the new development, and OLWQS together with the Osoyoos Oxbows Society and other environmental groups are in communication with the developer to try to ensure the development is as ‘eco-friendly’ as possible to protect this extremely fragile and unique wetlands habitat.
More info:
Osoyoos Oxbows Restoration Society (contact info)
What is an oxbow?
What are wetlands?
