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Melting glaciers may produce thousands of kilometers of new salmon habitat

science.org

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Re: Melting glaciers may produce thousands of kilometers of new salmon habitat

#12
post #8
post #3

So could opening up dammed rivers.

Why can’t we invent better fish ladders to get around dams?

Most dams do not have a fish ladder from what I have seen.

I have fished every dam on the river I live on (in IL) for about a 60 mile stretch. There is 1 fish ladder I can think of. Every dam removal project gets fought tooth and nail by locals who like how they look, or fishermen who like how fish bunch up under them.

Re: Melting glaciers may produce thousands of kilometers of new salmon habitat

#16
post #5

Cant access it (ddos protection from so much new traffic), so maybe my question would be answered. I wonder what salmon would habitat the ne habitat and how long it would take. Presumably salmon return to where they were born to spawn. So only the lost salmon would be able to populate the new habitat.

It generally happens pretty quickly. Salmon seem to all have a "stray rate", where some percent will stray from their natal river on their spawning run. It makes sense, as it allows for colonization of new habitat, or to revive extinct populations. A lot of the current salmon habitat from Washington north was under glaciers not too long ago. So they have been doing this exact thing for millennia.

Straying is partly why you can see salmon spawning above former dam sites, even shortly after removal. It's also why you will occasionally see salmon in a stream with no documented population (sockeye salmon on the oregon coast for example).

As for how long it takes for a population to take hold I'm not sure. But I have read about salmon populations getting completely wiped out by landslides and recovering in 50 years or so, including the same adaptations (for example larger bodies for navigating a steep gorge) that the extinct population held. So potentially pretty quickly in the grand scheme of things.

Re: Melting glaciers may produce thousands of kilometers of new salmon habitat

#19
post #3

So could opening up dammed rivers.

And how many more kilotons of fossil fuels would we need to burn per year to make up for the loss in hydroelectric power those dams give us?

0. But it would require giving up some creature comforts.
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