Scientists fear that if they are allowed to travel upstream, they could spawn, multiply and threaten the larger ecosystem of the Lake Michigan.

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The lake's owner, the Nature Conservancy, asks that they not: The ecosystem is home to the endangered 2-inch Borax Lake chub, which exists only here.

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Ikal Angelei, grew up around Lake Turkana, Kenya, home to a thriving ecosystem that supports hundreds of thousands of indigenous farmers, herders, and fishers.

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