Comments on: Controversial Study Says Dams Aren’t Killing Off the Pacific Salmon

By: Tuco

Tuco — Sat, 01 Nov 2008 02:02:01 +0000

The scope of the problem with most of the cold water species (esp. anadromous) is larger than one study can provide meaningful data. Its the overfishing, dams, siltation, overgrazing in there headwaters, disruption of riparian buffers that ultimately put them at a position where they cannot recover on there own. We are the only hope for them. It will take a large cultural shift to put our natural resources at a high priority and lots of time. Humans living high on the razorback can be reluctant to change.

By: Dan

Dan — Thu, 30 Oct 2008 23:54:44 +0000

Science–even environmental science–should be unbiased. Those who just assume that the dams are causing all (or most) of the problems could wind up hurting rather than helping the salmon. It’s vital that we perform studies like this one, to find out what is really going on.

With salmon populations as dangerously low as they are now, it is imperative we take meaningful steps, not emotional steps, to fix the problem. It would be pretty stupid to tear down all the dams, only to find (as this study suggests) that we haven’t thereby helped the salmon runs.

What if, instead, banning coastal-water salmon farming is the magic bullet?

By: Brian

Brian — Thu, 30 Oct 2008 19:29:12 +0000

Peter, several groups have been doing similar studies with adult fish as they come back to the rivers for the last 10 years. Survival of adult fish is relatively high. The vast majority of mortality occurs when fish are in the river or soon after they enter the ocean.

By: peter

peter — Wed, 29 Oct 2008 03:39:09 +0000

I understood the primary issue was not so much with reaching the ocean as returning to the river.

In my mind I just see little fishies swimming through the dams with the water flow while they are running, but swimming back up PAST the dams is much more difficult. Even if fish can get through the dams while they are generating, it would create so much of a bottle neck as to effectively destroy the population. That’s what fish ladders are for!

Next study: implant transmitters in mature fish caught near the mouth of the river as they return for smolting, and track how far each fish gets. THAT, I suspect, will be the much more telling number.