Friends,

This subject is just too good, or too hot, to drop. B-run asked us what we think about removing the 4 lower Snake River dams to help restore threatened fish stocks to that area. Backlash stepped up to inform us that the dams are not the problem here. And the rest of us chimed in with our bits and pieces and chummed the waters, so to speak. Things I found interesting in this discussion, and others like it, are: the problem is always something or somebody other than me. And it seems we each think we’re unbiased, at least relatively so, anyway. Well, my contribution is unresearched, completely biased, but fairly well informed.

What is the problem that causes depressed stocks of salmon and steelhead so that they have to be listed under the ESA? Well, let’s begin with this. There are two kinds of mortality to fish. Natural mortality, the sort that occurs absent any and all human intervention. Most fish populations sustained themselves over thousands of years without letup when all they had to contend with was natural mortality. An important thing about natural mortality is that there is nothing we humans can do about it. Egg to fry survival is always less than 100%, even in the most pristine environments, and smolt to adult survival is likewise always less than 100% in the ocean. Under the best of natural conditions, the survival of salmon and steelhead from egg to subsequent spawning adult is less than 1%. They naturally carry a lot of eggs to allow for high natural mortality in the very best, pristine, ecosystems even when untouched by any human intervention.

Enter the second source of mortality, human intervention, and you can readily see that there is not a huge margin for error. Increasing mortality by as much as 0.1% above natural background levels can have a significant effect on a fish population. But collectively we add a lot more mortality to that to a Snake River fish population, as well as other populations coastwide. The point I wish to make here is that no one source of human induced mortality is on any higher moral or ethical ground than other sources, at least biologically speaking. You might think a gillnet is less moral than pulp mill pollution, but to the salmon that died and didn’t return to the spawning grounds, the cause of death makes no difference whatever.

The problem with depressed and threatened fish stocks is that taken collectively, we add too much additional mortality to a fish population above natural mortality levels. I think fish biologists support the assertion that reducing any one source of mortality results in a proportionate increase in the number of fish entering the adult population. So if it is our objective to increase the size of an adult fish population, reducing mortality at any point in the fishes’ life history is a good thing and will result in some increase to the population. If fish populations are in really bad shape, like Snake River fall chinook, spring chinook, and steelhead (let’s talk native wild stocks in this case) then it probably makes sense to reduce mortality sources that have the greatest impact on the population.

So now let’s consider impacts. Here we may also find higher and lower ethical grounds in terms of relative impacts to the depressed fish populations. For instance, every Snake River fish must pass 4 Columbia River mainstem dams. Twice, first downstream and then upstream. Most Snake River fish have to pass an additional 4 lower Snake River mainstem dams as well (Walla Walla R. and Tucannon R. fish have fewer). This eight dam complex imposes an estimated juvenile fish mortality ranging from 50 to 80% according to the scientific reports. Then commercial and recreational fishing used to harvest as many as 70 to 85% of adult fish depending on species, time period analyzed, and so forth. Directed harvests are presently much lower, but are still a significant effect on the most depressed stocks. Let’s see, increased loads of fine sediment can reduce egg to fry survival from highs of 30 - 35% to less than 10%, or even 1 or 2%.

It’s harder to quantify the total impact of other effects, but I don’t want to leave anyone’s favorite out. So let’s mention road building, logging, dewatering, irrigation diversions, M&I diversions, ag runoff and return flows, industrial and sewage effluents, mining. Please add your favorite in case I overlooked it; after all this is a stream of consciousness, unresearched, post. The point I wish to make here is that some human induced causes of mortality affect a lot of fish, like the Snake River dams, and some causes, like ag runoff or a podunk irrigation diversion on a small Salmon River tributary, affect relatively few fish, even if they are very egregious offenders. This line of reasoning leads me to conclude that the very best way to restore Snake River wild salmon and steelhead is to reduce mortality from the sources that cause the highest rates of mortality to the greatest proportion of the Snake River salmon and steelhead populations.

Now if objective evidence indicates that the 4 lower Snake River dams induce a higher rate of mortality to more Snake River fish than any other source of human induced mortality, then that should be the location where we place our highest priority and greatest effort to reduce, or even eliminate, mortality to anadromous fish. And wouldn’t the next stroke of logic be to compare the cost of fixing Snake River dam mortality to the cost of whatever alternatives would be necessary to achieve the same fishery benefits of fixing the mortality problem caused by the Snake River dams? The fish really don’t care. Reduce human induced mortality by enough, and the fish will begin returning in ever greater numbers, up to the capacity of the remaining habitat. Don’t, and . . ., well, they won’t.

Some random responses to other points raised:

The Grande Ronde gets large returns of steelhead in spite of the dams because, a) a bazillion hatchery smolts are released there every year. They nonetheless still take a pretty hefty mortality hit from the dams.

The Hanford reach gets a healthy return because the 4 lower Columbia dams don’t cause as much mortality as the 4 lower Snake dams. But, chinook further up the Columbia are endangered! Guess what? Priest Rapids, Wanapum, Rock Island, and Rocky Reach aren’t fish friendly enough to sustain wild fish populations upstream of them. So right now, it looks like the 4 lower Columbia River dams are about the limit (all other sources of human induced mortality being equal - which they aren’t) that the fish populations can handle and still exist.

Lower Columbia River coho are near extinction because the states have managed for hatchery harvest rates, in excess of 80 and 90%, that no wild population can withstand. Therefore, wild coho are at or near extinction. Right, dams are not the only way to wipe out a fish population.

Silt behind the Snake dams. This is not a sufficient reason to avoid tackling the Snake dam issue. Most of the worst of the silt will blow out in a couple years. A worst case comparison? Try the S. F. Toutle River that was partially buried by the Mt. St. Helens blast. Not nearly as bad as the N. F., but also came back into fish production in a couple years. Come on guys! This one’s a smoke screen, a whiny why we can’t do anything but ring our hands and point at other causes of the problem. A feeble excuse for doing nothing. My speculation? Within 3 years after breaching, fall chinook will spawn successfully with good egg to fry survival.

Ladders over Hell’s Canyon won’t restore anadromous fish to the upper Snake. Removal of those dams might not do it, either. Hence, no uproar at the moment. Also those dams are owned by Idaho Power, not the U.S., altho that may not matter. But the real issue is restoring the lower Snake first. It won’t do any good to restore the upper Snake if we haven’t repaired the lower.

There is no scientific evidence that says dam breaching will restore the fish. Correct. There is also on scientific evidence that says it won’t restore the fish. Depends where you wish to place the burden of proof, I guess. And there’s ton’s of scientific evidence about what hasn’t worked worth a hoot! Yet, we keep putting our efforts in things that don’t work because those efforts hurt us the least. Yeah, well that’s pretty smart reasoning! Sounds like I’m ranting now, huh?

How about banning all commercial fishing for 1 year? Hmmm, I’ll bite. Let’s ban all fishing for one year, BUT let’s also ban all hydroelectric energy production from the 4 lower Snake dams and the 8 Columbia dams for the same year - just pass the water by. Let’s just see how fish respond to that, while we’re at it. See, fish don’t care what the source of mortality is. Mortality just has to be low enough so that some of those 1% of the survivors from eggs can survive to spawn. Death by commercial fishing is no worse to a salmon than death by hydroelectric turbines or warm slackwater reservoirs.

Salmon are declining in all west coast rivers, dams or not. True. When ocean conditions are not as favorable to survival, all stocks are affected. But which stocks are most affected? Those that have additional problems. Remember, natural mortality is one of the things we really can’t do anything about. Human induced mortality is something within our capability to influence. In spite of low ocean survival, those stocks from the healthiest ecosystems are presently performing the best. And it ain’t the Snake. Surprised?

If the dams kill so many salmon and steelhead, they would be long gone by now. True. And some of them are gone now. But anadromous fish are very resilient. A species that counts on having less than 1% of its progeny survive to reproductive age has to be resilient. The dams do kill so many - its in the reports - but they don’t kill enough of some stocks to completely wipe them out. But they do seem to be trying. And most of the anadromous fish returning to the Snake are of hatchery origin. The human induced mortality rates are just too high for wild salmon and steelhead stocks to persist upstream of Lower Granite. Most of the remaining wild fish populations are, or have been, augmented with hatchery production. I’m not sure if any actually remain that have had no help from hatcheries. Looks kinda’ borderline. Maybe the dams do kill so many that the fish would be long gone by now except for the hatchery intervention. Need expert input here. Any volunteers?

Oh, and a good one. The largest chinook run returned 50 years after Bonneville was built. So? That’s merely the largest chinook run counted, since they didn’t count runs before Bonneville made it possible. All they could count previously was the commercial salmon pack. And the commercial canning industry had a hell of an impact on chinook. The big count was by no means the biggest run; likely far from it.

Obviously, there are no simple or easy answers to complex problems. I've made this lengthy post to express how fish mortality works in salmon and steelhead populations and how human activities nudge mortality rates over the edge that fish populations can withstand. And I hope I've helped you understand that the problem is you and me, but that every thing we do to reduce mortality to fish helps. I just happen to think it makes the most sense to address the cause that has the largest effect on the greatest proportion of the fish.

Especially so if the consequences are bearable. I believe a strong case has been made that we can bear the breaching of the lower Snake dams. Wheat will still get to market - by rail rather than barge. Irrigation for the 13 affected farms will still happen, they just need additional pumping. That's a pretty small technology fix. The 4 lower Snake dams provide absolutely zero flood control benefits, so please don't be misled by arguments to the contrary. And the energy from those dams is less than 5% of the regional supply and no more than 12% of BPA's supply. Well, BPA exists for the sole reason of marketing surplus federal energy. If these dams don't produce any, BPA doesn't have to worry about marketing it. And the energy loss to the region won't be noticed since we continue to have an energy glut. I just can't think of any impact from breaching so great that we as a society cannot absorb it.

If my reasoning is flawed, please so indicate.

Sincerely,

Salmo g.