Ah CM the old bug a boo. That the food chain harvest thing is absolutely correct but I have yet to catch many malnourished Chinook. That it effects the overall health and survival is undeniable. Then this the % of the run that is three year old fish is elevated above the past. For GH it looks like this. In 1986 by age group percentage of the run 3 - 13.2 / 4 - 23.8 / 5 -35.3 / 6 - 15.2. Then this in 2019 they were 3- 17.8 / 4 - 59.8 / 5 - 21.2 / 6 - 0.2 which is way past awful.

Bottom line for many generations now ( since the 70's ) our Chinook populations have had substantial increase in 3 yr spawners ( small ). A huge decrease in 5 & 6 year old spawners and 4 year class and increase in % of the run. Simply put we have increased the number of small fish and dramatically reduced the number of large fish spawning and this has resulted in smaller fish. Now the genetics are not lost but rather humans have altered the natural selection process. Remove human interference and natural selection will return the fish to what it was was if environmental conditions permit. Just went full circle to the food chain thing.

According to my research contacts, you don't see the malnourished Chinook as they die. What seems to be happening is that the larger Chinook are doing just fine, get up to adult size and head home. When they encounter warmer water the metabolic rate goes up. There are not enough calories in the food per kg eaten, so they essentially starve.

Plus, the salmon are getting smaller at age. In the old paradigm, where fisheries took the larger fish, the fish returning got younger but were essentially the correct size for age. Just more age-3 and less age-5 but the age-3 fish were properly sized for age. Now, the age-3 fish is smaller because they have lower quality/quantity of food to eat.

Perhaps we can put the salmon size into antler terms. A buck will get to be a 4x4 if it has the right genes and, most importantly, if it lives long enough. Now, in addition to killing off the bucks so they don't get old, the food no longer has the calcium supply, so what does grow is smaller.

I have a no disagreement at all with your thoughts other than your limiting the problem to food / environmental only. I remember a WDFW hatchery guy listening to the argument but it was about Coho size. I still remember his terse response. How do you start with a 10 to 12 lb average brood and get to a 5 to 7 lb fish. Net the hell out of them with a mesh size that allow smaller adults to escape for generations resulting a higher portion of small fish in the gene pool and hatchery eggtake. A fish and cow are very different but all creatures can be modified by altering natural selection be by natural conditions or those inflicted by humans. In the end I imagine it is a combination of both sides of this coin.

That's true in that what spawns is what isn't killed. That is likely more common with hatchery than with wild fish because of lower exploitation rates. But yes, fish the **ck out a run and you get very little both in numbers and size.

Heck, one year when I was in hatcheries the adult coho were, in many cases, smaller that what was "always" called a jack. CWT's proved it. Plus, fecundity is directly related to size. Smaller females have fewer eggs......

Didn't "Digger" Phelps essentially prove that the Puyallup Coho were shrunken in size due to successive years of selecting the larger fish by gillnetting? Doesn't this harvest of any salmonid by continually taking the larger specimens theoretically apply?

Many years ago, the hatcheries selected the largest fish available for spawning. I think that practice was terminated years later by a mandate to take fish across the size spectrum. Don't know what the practice is now.

The thing I learned about fish being around hatcheries over the years is that decisions have a real and nearly immediate effect on the creature. Culture decisions normally isolate this to the hatchery production ( dependent on straying ) but harvest effects both W & H. It just takes much longer to show in the natural production.

Been away from the game a bit Tug but they did move to take eggs from the full run spectrum rather than a certain timing or using run compression. The early timed hatchery Coho on the Satsop came from taking the eggtake from the front of the run only compressing the return timing window. You end up with a fish that is inclined to return early rather than over eight weeks.

It was know before Phelps. Bill Ricker, of Ricker Curve fame, looked at the changes in size over time for the five species of Pacific salmon. Fishing definitely was correlated with changes in size. Most of the time, it made them smaller. Sometimes, larger. In that case, fishing for sockeye, with the smaller sockeye gear, selected out the small chum. So, the chum run actually got larger.

Back in the 80s, Skagit coho were routinely in the hole and required protection. State and tribes fished the Bay and river for chum with, I believe a 6 or 6.5 inch minimum mesh. Caught lots of chum and no coho. December 1, end of salmon management, start of steelhead they dropped to 5 inch. Bam, coho showed up in the catch. For a month they hadn't been there, because they were smaller than the chum.

There are lots of by catch issues out there....

It's genetics. The genes that aren't killed are what you use. Very intensive selection. I know lots of folks complain, or did, that hatcheries breed "non-biters". Not intentionally, but if the 10% of the return that you use to spawn was too small for the nets, too early for the intensive fishery, and didn't bite a hook just what do you think the kids will look like?

A guy I worked with for years was an avid fisherman. He always claimed if you used the right gear in the right place in the proper manner you can get a Steelhead to bite, all about knowledge and skill. Salmon the same applies but if you could get one out of a hundred to bite as they swam by you were lucky. Next guy the same up stream but salmon once out of the salt their behavior is all over the place. Thing is if you fish a hatchery run for many generations with pole you will steadily remove fish from the run that inclined to be aggressive when in fresh water. I read someplace that they were going to add wild fish to an eggtake to try to counteract this.

Those wild fish still had to get into the escapement by not biting.

yup, yup & yup