Salmon cannon helps fish migrate
Dams generate hydropower, the world's largest share of clean energy. But for many freshwater fish, they're a barrier and a major reason their populations are struggling.
This Seattle companyis helping fish to migrate around these obstacles, shooting them through a tube on a cushion of water — with no extra stress, injury or lower survival rates.
Migrating salmon have found a new way to get where they're goingImage: Thomas Kline/picture-alliance/Design Pics
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