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Success stories — Okanagan River
Canadian and U.S. tribes take steps toward international sockeye salmon restoration Before there was a border between Washington and British Columbia, sockeye salmon grew up in the chain of lakes that form the headwaters of the Okanagan River. Over time, a border was established, the river acquired a name with two spellings — Okanagan in British Columbia and Okanogan in Washington — and the salmon runs steadily declined, largely from the impact of the chain of hydroelectric dams in the United States between the headwaters and the Pacific Ocean. At one time, lakes in the Okanagan basin accounted for more than 41 percent of the lake rearing habitat accessible to sockeye salmon in the Columbia River Basin. Today, biologists from both countries are working on an experimental project to reintroduce sockeye into Skaha Lake, one of the natural impoundments formed by the Okanagan River in the headwaters region of south-central British Columbia. Skaha Lake is immediately south of the city of Penticton and north of Osoyoos Lake, which is split by the international border. Sockeye salmon once spawned in the upper reaches of the river, but McIntyre Dam, an irrigation diversion completed in 1954, now blocks fish from entering. The dam is the end of the road for anadromous fish in the Okanagan basin. If the current work determines that the sockeye reintroduction likely would be successful, fish passage would be built at the dam. Currently, the only sockeye population is found in Osoyoos Lake, the lake that is split by the international border, and suitable rearing conditions only exist in the northern one-third of the lake. The abundance of that population has declined significantly over the last 50 years. Research now is under way through the Council's Columbia River Basin Fish and Wildlife Program into the feasibility of reintroducing sockeye into Okanagan Lake, which has a large potential rearing capacity for sockeye. However, it is difficult to assess the risks and benefits of reintroducing the species into Okanagan Lake as there is the potential for interactions there between sockeye and other fish populations. Fish and wildlife agencies and Indian tribes from both sides of the border decided on an alternative: reintroduce sockeye into Skaha Lake as an experiment. Knowledge gained from the Skaha experiment would be useful in determining whether it would be feasible to reintroduce sockeye into Okanagan Lake in the future. On the American side of the border, the Skaha Lake project is being managed by the Colville Confederated Tribes. In Canada, the project is being managed by the Okanagan Nation Alliance. The Okanagan Nation Alliance, in coordination with Fisheries and Oceans Canada and the British Columbia Ministry of Water, Land and Air Protection, has nearly completed the three-year risk assessment project. The project has four objectives:
Funding for the project, which began in 2000, is anticipated to total $802,000 over five years. Results to date indicate that risks are lower than anticipated. Spawning habitat upstream of McIntyre Dam could support 9,000 pairs of adult sockeye, and access to Skaha Lake would result in a three-fold increase in rearing habitat. The next step is to provide fish passage at McIntyre Dam and install a fish diversion screen on the irrigation canal intake. A proposal to begin that work was submitted by the tribes for funding in 2003, but it was rejected, for now, because of Bonneville's decision to reduce its fish and wildlife funding this year in response to its financial crisis. Meanwhile, the tribes are going ahead with an evaluation of strategies to reintroduce sockeye into Skaha Lake. These include strategies to provide access so that fish could recolonize historic habitat. |
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