Salmon getting smaller

There is some interesting ongoing work in AK that shows salmon getting smaller with age. Some appears to be due to either being outcompeted by other species (Pinks) or switching to less nutritious food.

The second, less nutritious food, has a real hidden pitfall. In order to survive in warmer water, salmon need to burn more calories-being poikilothermic. With less energy per bite, a full stomach supports smaller size because a large fish does not have the energy for metabolism.

So, if our waters are warming, the salmon need more nutritious food to maintain (or recover-see Elwha and Kenai) "lost" size. Which means if we want more and larger salmon we need to leave more of the lower levels of the food chain in the ocean.

Couldn't nets be selectively harvesting the big fish genes out of the population as well?

I think that in many of the AK stocks the primary fishery is hook and line but the problem is sowing up across species. Except some pinks, who seem to be the one of the "bad guys" in this story.

AK does its Chinook damage in the ocean ( just as they do PNW fish ). Manage rather well otherwise. Just can"t turn loose of that commercial bowl offshore. Yes the pressure of trollers in the ocean places extreme genetic pressures on the fish as you remove a greater % of 4,5,6 year fish from the pool. Absolutely known as to cause and effect but not talked about much. It does not fit the harvesters talking points.

I appreciate the discussion about the damage that the marine mixed stock salmon fisheries do to age, size, numbers, future, and so on. But what the ocean is trying to tell us, in the way in which sizes are now changing, species are vanishing, and so on is that the whole damn ocean is in trouble.

If salmon managers continue to look only at salmon the fish are lost. We (all managers) have to consider the ecological consequences of what harvesting "their" resource does. Taking too many herring cuts down salmon food. Taking too many Chinook removes Killer Whale food, allowing too few salmon spawners takes away bear food. And the list goes on and on.

The long term health of our salmon runs depends on taking and doing a holistic view of the oceans and uplands that will include the future of humans and natural resources. It's linked. And ignored.

That's why I use superbaits. I'm a conservationist. Sometimes I do trick them in to eating their ovum.

That broadens the conversation CM. That size is dependent on food is true. Take the recent Coho crash. From what I observed about 2/3 came normal but about 1/3 were undersized. You always have what are called dinks but not in that portion. You can not harvest the food chain top to bottom and think that those at the top will not be effected. So long term yeah the food chain will come home to bite us. That said again since the post Boldt times the non treaty commercial fishers and Rec fisheries moved North to Alaska and took the PNW fish there in front of the tribes. The massive impacts of all forms of commercial harvest in the Bering Sea and Gulf of Alaska are the primary driver for the crash of Chinook. Long term yup the food chain thing will come home to be sure but that pressure in the marine area is the primary thing that is simply continuing to do what it has for 30 years. Decimate salmon.

But as long as we all stay in our secure silos we don't have to think about the bigger issues.

We fish down the food chain, which works if everything in the chain is reduced by the same amount. But when you want to expand human use, Killer Whales, pinnipeds, cormorants and terns then you put more pressure on a resource that your management is making smaller.

One of my better bosses (although the bar for bosses generally was on the ground or buries, some were way above ground level) said that salmon were abundant in the past because salmon were abundant. What he meant was that we had a lot of salmon to catch when we had lots of them spawning. We now go the other way, like good Wall Street Bankers. What is the minimum investment I am forced to make in order to maximize my return to myself.

Interesting word for the day,

Depensation/critical depensation:

When the level of depensation is high enough that the population is no longer able to sustain itself, it is said to be a critical depensation. This occurs when the population size has a tendency to decline when the population drops below a certain level (known as the "Critical depensation level"). Ultimately this may lead to the population or fishery's collapse (resource depletion), or even local extinction.

There is another aspect that goes the other way. That is, the resource has different stability levels.

Say, originally, Skagit steelhead were stable with run of and an escapement of 150000-pre-human removals and all the salmon.

During tribal times the run was 130K with 10K removed along with some of the salmon.

Now, we are to about 10K more or less along with a few salmon.

Each time the fishery, or habitat destruction, changes productivity the steelhead adopt a new level. They are relatively stable at that level so long as the rest of the conditions such as salmon, stream temp, flows, ocean temps, estuarial quality remain rather constant.

One of the lessons that I learned early, but fought against for a long time, was that there is no single MSY, or optimum population, or even optimum escapement goal because there are so many conditions that go into it. Unfortunately, our fish find themselves in a very unstable situation where the only constant is kill as many as we think we can today.

"Each time the fishery, or habitat destruction, changes productivity the steelhead adopt a new level. They are relatively stable at that level so long as the rest of the conditions such as salmon, stream temp, flows, ocean temps, estuarial quality remain rather constant.

One of the lessons that I learned early, but fought against for a long time, was that there is no single MSY, or optimum population, or even optimum escapement goal because there are so many conditions that go into it. Unfortunately, our fish find themselves in a very unstable situation where the only constant is kill as many as we think we can today."

Can I get an, Amen!?

AMEN

I agree with Spokey. Selective harvest has been removing the largest genetics for generations before non Indians got here.
Salmon have continued to get smaller, just at a way faster rate in recent times. Their is no maximum size limits in Washington, so sport and commercial harvest has also has contributed.
If anything, Pink Salmon are a example of this. Because of there fixed life cycle, they have shrunk less. Our harvest model attacks the multi year class fish most.
The average Alaskan chum this year is less than 8 pounds.

Lol I was just asking the question. I believe all the bottom of food chain harvesting is hurting lots of fish populations in ocean. How many tons of krill are harvesting just so yuppies can feel younger & healthier by ingesting powdered or oil krill products? Also I'd bet the scent market does it's fair share of damage. By far I'd think (and not t sound all alt right or anything lol) the Asian markets are by far the biggest problem since the shear amount & variety of sea life that gets sold or bought there. Ain't nobody in the US gonna stand up and slow that down. The snowflakes might create a "spafe space" right in the front yard of any politician that tried.

I am not a scientist but from a purely observational standpoint I think salmon populations were most impacted when the herring roe harvest started up.

I apologize for assuming. To answer your question, selective harvest of the largest fish is the most significant reason for decline in size.

If the Chinook salmon lived 7-8 years they would work up the food chain and eat our precious hatchery fish of all salmonids.
They do not grow large enough, and very little predation takes place.

From NOAA webpage regarding what forage fish are used for.

“The small, open-ocean fish that are caught in industrial fisheries are consumed directly, used as bait in commercial and recreational fisheries and in lobster traps, used as ingredients in the feed for aquaculture, pigs, poultry, cattle, and pet food; and are converted into fish oil pills.”

It is the larger fish competing with humanity for their food. No surprise how that will end----- BURP.

Which gets back to the point that all of of our natural resource problems trace back to humans and their population. If we want salmon in the future, or deer, or bears, or ducks, or whatever we will need to face the population issue head on.

Not to decide is to decide.

As they continue to lose habitat through development.

Anybody from California know what deer harvest in the state was in 1960 versus today?

Not a lot new in this discussion, W. E. Ricker in 1981 published a paper where he pointed out chinook had been decreasing in size since 1920. The reasons were all of the ones discussed in this thread. All salmon species and populations have been changing size and age, increasing and decreasing over time. I think of it as evolution, adapting to a changing environment. Animals with a short life cycle do it faster. We humans in some populations are slowly getting larger and older but it is not in all populations.

Yeah, but WDFW and the Feds, when reviewing Chinook fisheries for rules under ESA, concluded that fishing has no effect on Chinook size. Of course, the data set was the most recent 15 minutes but it allowed the marine mixed stock fisheries to continue which was the goal of the exercise, anyway.

This may ultimately prove true, but I will continue to resist the notion that humans and the rest of the Earth can't coexist, because asking people to stop having babies is rather a poor survival strategy, and dooming us all to a fate we can't avoid won't do anything to motivate people to change (which I think we can all agree must happen).

I believe the problem is less about our numbers than it is about profit-motivated greed. No matter how many resources there are available, a few people will always strive to gain control of those resources for personal profit. There are a lot of greedy behaviors we could clean up that would at least prolong the slide toward extinction significantly. Before we throw our hands up and declare the existing habitat isn't capable of more than it currently delivers (and will only get worse until we start killing babies), we should meaningfully reduce mixed stock harvest for a decade or two, to make sure we're right. We've seen plenty of evidence that even the current habitat, given favorable ocean conditions, can still return some very catchable numbers of salmon... especially when NMFS and the Tribes underestimate the run.

If we refuse to change our greedy behaviors, then yes, Humanity and the Earth are doomed.

Look at the areas with way lots more people and a longer history of human habitation than North and South america. What's happening to wildlife in Africa? They coexisting well with the people? Or India and China?

The earth has a fixed amount of resources. We are not creating more land, water, minerals, etc. We do recycle, but no more is made.

We can, to some point, conserve our way out of short term problems. But not in the long term.

Say a river, in its pristine state, supported 1000 people with their annual need of salmon for food. You now have 2,000 trying to live of that run. Or 3 or 4 or 10,000. At some point, the run can't sustain itself. Before it hits that point, the other resources that ate salmon or depended on the spawners for nutrients have to decline because humans have taken "their share". Same argument holds for water and any other resource.

People seem to think that our existence is somehow outside of the rules that govern ecosystems. We're not.

We ended market hunting and big game and birds are as good, if not better, than ever before. Being a land based species, we could "see" the detriment we caused by MH and course corrected with pretty great success (overall and at least in NA).

We can't "see" what we are doing to the fish. "BUT it's a big ocean!". Time to end market fishing no? It'll "never happen", but it should shouldn't it?

I doubt that current numbers for many terrestrial species are as high as , say, the 60s/70s. Some, like suburban whitetail, introduced wild turkey, white geese, and urban geese are exploding many others are showing declines. You are right that conversion fro market hunting to recreational "saved" many species. Until the recreational demand exceeds the supply. Then we get limited entry, special tags, etc.

NA certainly has "better" wildlife numbers than most of the rest of the world. We also have fewer people.

Actually he is correct. The human species has been the most destructive species or thing short of a comet or meteor in the history of the planet. European culture being the latest and greatest destroyer. Fact is unless the human population regulates itself as to population to zero growth the outcome is known it is not a secret. Growth of a population to fuel economics will achieve that but the greater the growth the greater to the environment damage. We try to contain it with laws but the reality is it is window dressing as even if we stop the visible damage you have feed, and house people. To construct something you usually have wipe out the natural order to do so.

Want to find out what the how to find out non PC? Advocate Zero population growth and mandatory growth management. Hell in the 70's that was discussed in Puget Sound to prevent the destruction of the Sound and other natural things. The folks in PS have not seen the tip of the iceberg for the coming bill for that in PS yet which is in the many many billions.

So as I hop off the box this. Humans and the natural order are 100% non compatible. Salmonids on steroids. Each time we add a house, car, boat, just about every damn thing it is another nail in the coffin. If you were born in this state and accepted the growth your responsible. If your parents moved to this state then the a equal share of the blame is that group and frankly likely more.

The discussion is along the lines of "A Christmas Carol" and the Ghost of Christmas To Come. My point is we have a choice. Not advocating for a particular action but we have come to a fork in the road. Which one do you want to take?

Weren't the salmon here smaller because they were starving because the blob killed all their feed? If we want to rebuild our stocks we might look south, I mean way south. Chile and their Austral Kings that are originally from the cowlitz yet they have some massive fish return to their rivers. How?

Do they dredge offshore collecting the salmon as bycatch? Do they fish commerically for them in the ocean?

My guess is they have big ass fish there because they are allowed to stay out 5-8 years and there is plenty of feed.

AK is gonna wipeout all their fish in no time and we would see greater returns if they would layoff the southern stocks. Change their openings and their locations so we can see some fish return.

We could blame our fish being smaller on the Blob but the smaller fish in AK are north of it and still starving. Some are. Those that feed lower on the food chain (pinks) are even showing some increase in size.

As I read more there is a real [Bleeeeep!]-storm occurring on the Pacific Coast from the Salish Sea (at least) on north into SE AK and maybe beyond there. The problem is bigger than one state or even one country, and since we have 3 involved in Pacific management (US, Canada, and Alaska) there are some real problems in getting to a solution.

Somewhere on this BB this came up. The salmon reared in South America commercially and other many had there origins from PMW hatcheries. Their size has increased due to the fact they do not have marine fisheries and are evolving back toward themselves. The egg sales I did were all Coho and went to Chile if I recall correctly. I think the Cowlitz sold surplus Chinook eggs but it has been a bit back. Long and short of it feed being down reduces a fish for his time but feed back the size is back. The gene pool removal by marine troll and sport for the 5 & 6 yr old fish has downsized our Chinook but they will also recover over MANY generations with no harvest.

You see there is a answer but lord your not going to like the price. Catch here is they cannot be wiped out to recover and spawning success will be greatly reduced by the smaller adult size extending the time line. In other words we manage Chinook about as ass backwards as a humans can do ( and we do some really stupid things ) and we do it with great fanfare each year. We have met the enemy and it is us.

What we are creating with Chinook is piscivorous Chum. They used to use big rivers because big fish could move big rocks. Now, with majority of them being large-end chum they can successfully spawn in small rivers and even large creeks. We may have, unwittingly, guaranteed Chinook's future by forcing them into smaller streams that we won't be damming for hydro.

Two Indian tribes in CA are trying to bring back some New Zealand Chinook to restore their local stock. Originally, those fish were sent to the Antipodes; now they represent the "purest" genes as hatcheries and a century of top-shelf management has mongrelized what's left in the upper Sacramento.