Nate Rott

The new United Nations-led report offers the most comprehensive look at the world's freshwater fish migrations ever.

And its findings are sobering.

Migratory fish populations have fallen by more than 80% globally since 1970.

325 different species, it says, should be considered for protection.

And protecting those species will require international coordination, the assessment's authors say, with rivers being treated as connected systems.

A challenge, some scientists say, given the broader state of international affairs.

Nate Rott, NPR News.

For much of the world, normal is gone.

The new United Nations-led report offers the most comprehensive look at the world's freshwater fish migrations ever.

And its findings are sobering.

Migratory fish populations have fallen by more than 80% globally since 1970.

325 different species, it says, should be considered for protection.

And protecting those species will require international coordination, the assessment's authors say, with rivers being treated as connected systems.

A challenge, some scientists say, given the broader state of international affairs.

Nate Rott, NPR News.

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