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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

#31
post #8

Earlier quoted context omitted.

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.

Fish ladders are also imperfect. Anglers know this, as we fish the deep pools created at the bottoms of dams -- many fish will stage/rest there, and some will simply get stuck there.

They also don't solve the problem where dams slow and warm the waters running through them. Trout and Salmon need cold water to survive.

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

#32
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?

Aside from the point that most dams don't produce a ton of power, salmonid spawning in the ecosystem also adds nitrogen to banks that encourages vegetation growth, which is beneficial in many ways for both our water supply (e.g. shade helps prevent evaporative losses, trees provide beavers opportunity to build habitat to increase net groundwater storage) and for carbon sequestration via plant growth. The American west has a drought resilience problem and restoring salmon/trout/beaver habitat can be an effective way to attack the problem on several levels. Dams are particularly damaging to Salmonids, both by acting as spawning barriers AND by warming the water to a level that can make survival difficult (salmonids need cold water).

Look at dams like Oroville and Hoover now -- despite producing a lot of electricity, they are not resilient to drought, and river systems lose a lot of drought resistance when you add dams. When you dam a river, you slow and warm the water -- this threatens entire ecosystems adapted to survival where the river runs.

Particularly in salmonid / coldwater fish habitats, dams are pretty damaging. If you want to learn more about the subject, there are a lot of books & documentaries about the Eel river that are worth reading and watching -- the Eel is a good case study in what happens when you dam a river, and what happens when you un-dam it.

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

#33

Earlier quoted context omitted.

There are 84,000 dams in the United States. More than one a day since we became a country. Most of them don't generate any meaningful electricity, but they do disrupt habitat for many native fish species. I would like to see them all destroyed. We can find electricity elsewhere.

electricity is not the only reason we dam rivers, millions of acres of agriculture is irrigated via damning and diverting rivers

I guess irrigation can be "damning" to rivers :)

Jokes aside, everything's a tradeoff and while flood control / irrigation is helpful to farmers, it can also introduce a resiliency problem in quake zones, since a dam breakage can cause devastating floods. Actually, it doesn't even have to be an earthquake. Exhibit A: https://en.wikipedia.org/wiki/Oroville_Dam_crisis

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

#34
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?

Some hydroelectric power plants actually have greater emissions than even coal power plants, and that's ignoring that dams are much worse for the extended local ecosystems.

The dams in the Pacific Northwest have decimated the wild salmon population. Salmon are big, meat eating fish that sustain several other animals, such as the Southern Resident orcas. This population of orcas is literally being starved by us destroying the salmon population., amongst the other challenges they face due to humans, such as poisoning and toxicity.

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

#35

I think when trying to predict the future of climate change, you’ll find every model imperfect (even if it can tell you important truths about what may happen). If you try to make specific predictions, you’re going to turn people off. It’s far better to frame it as a matter of, “Look we don’t know what’ll happen and since we only have 1 planet and pollution is bad, we’re going to try and minimize the impact we have,…

But, if that were the right approach, you’d never change anything. We’d have never left the caves. The question is not whether we alter the natural environment. It’s whether we have reason to believe the benefits of those changes may outweigh the costs.

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

#36
post #8

Earlier quoted context omitted.

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.

> gets fought tooth and nail by locals

The cause of so many damn problems in the U.S.

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

#37

I think when trying to predict the future of climate change, you’ll find every model imperfect (even if it can tell you important truths about what may happen). If you try to make specific predictions, you’re going to turn people off. It’s far better to frame it as a matter of, “Look we don’t know what’ll happen and since we only have 1 planet and pollution is bad, we’re going to try and minimize the impact we have,…

> ... and since we only have 1 planet and pollution is bad ...

There is a high correlation and probably causal relationship between increasing global pollution and improved living standards. It is extremely unclear that "pollution is bad". Someone taking a strictly data driven approach could reasonably conclude that pollution is good.

There is a reason that the pro-environment types are struggling to have an impact on actual policy. Their ideas have, up until very recently with the relative cheapness of solar and wind, been likely to doom us all.

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

#38
post #34

Earlier quoted context omitted.

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?

Some hydroelectric power plants actually have greater emissions than even coal power plants, and that's ignoring that dams are much worse for the extended local ecosystems. The dams in the Pacific Northwest have decimated the wild salmon population. Salmon are big, meat eating fish that sustain several other animals, such as the Southern Resident orcas. This population of orcas is literally being starved by us destro…

> Salmon are big, meat eating fish that sustain several other animals

So are cattle. Sounds like we just saved a bunch of carbon so we can keep eating steak for a while.

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

#39
post #37

I think when trying to predict the future of climate change, you’ll find every model imperfect (even if it can tell you important truths about what may happen). If you try to make specific predictions, you’re going to turn people off. It’s far better to frame it as a matter of, “Look we don’t know what’ll happen and since we only have 1 planet and pollution is bad, we’re going to try and minimize the impact we have,…

> ... and since we only have 1 planet and pollution is bad ... There is a high correlation and probably causal relationship between increasing global pollution and improved living standards. It is extremely unclear that "pollution is bad". Someone taking a strictly data driven approach could reasonably conclude that pollution is good. There is a reason that the pro-environment types are struggling to have an impact o…

This is why compartmentalizing things as "good" or "bad" is unhelpful. It's rarely so simple. Sure, there are aspects of polluting behaviours that ostensibly raise the quality of life for many people, but that doesn't mean you should ignore the long term impact of that behavior, especially if it has a provably negative impact on the planet. You have to look at the whole issue, not just the short term positives.

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

#40

Maybe more salmon will set off a chain reaction that cools the planet?

As a species, we eat almost any kind of meat, from chicken to beef so if there's more salmon, we sure as well will eat more of it.

There's a popular meme for this "This looks like free real estate"

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