Tundra swans are dying along the Coeur d’Alene River floodplain. But this isn't a new problem.

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It happens every spring, and this year is no different. An average of 150 tundra swans are found dead in the Coeur d’Alene River Basin. This year, Fish and Game staff in the Panhandle Region are getting multiple calls about the dead birds.

The swans are being poisoned by waste from old mines as they migrate through Idaho on their way to breed in Alaska. For much of the last century mine waste was dumped in the Coeur d’Alene River and its tributaries. The marshy soil sucked up toxic metals, like lead. It’s estimated that 95% of the wetland habitat in the lower river basin has levels of lead high enough to kill the swans and other birds.

Tundra swans are even more vulnerable to the poison because they burrow into the mud to eat roots and tubers.

Working together, state and federal authorities and the Coeur d’Alene Tribe are trying to stop the deaths. A short term solution is trying to keep the birds from landing in contaminated areas and raising river levels to keep them away from poisoned sediment.

Longer term, the Restoration Partnership hopes to restore the habitat so the birds can safely migrate through the region. The Partnership has already restored 465 acres of marsh and wetlands for the swans and other birds. More projects are planned.

Find Samantha Wright on Twitter @samwrightradio

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