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[andrew5]

Hi guys,

It seems everyone has sockeye in their mind these days, and though I wish I could change things up with a topic other than sockeye, I did find myself wondering if the "problem" with hunting could be true for the sockeye fishery as well.

the hunting "problem" (in quotations because this is a fishing forum, and I don't want to open that can of worms) is  as fopllows:

Using the cariboo herd as an example (it translates well to the sockeye... large group of migratory animals). All of the factors that kill off the cariboo herds during their migration (wolves, bears, climate etc) kill off the weakest of the animals, and the strongest are left to procreate after reaching the breeding grounds. Hunting, on the other hand, is often centered around harvesting the biggest, fittest percentage of the populatin, essentially decreasing the top end of the gene pool.

With the sockeye run, I wonder (and am far from sure) if the same thing applies. I know that there are different runs of sockeye (harrison and others), but I am pretty sure that the nets have gone out near the beginning of the sockeye appearance this year.

If the earliest sockeye were caught, with the later fish in any given run allowed to go through, would this be similar? I wonder if the strongest, healthiest fish, make it to the system first, while the less healthy fish take a little longer to reach the spawning grounds. Surely fish arriving to a spawning ground first would have the pick of tthe redds for their eggs, so this would be nature's way of rewarding the fittest and aplying Darwinism to the reproduction cycle.

Does the DFO consider this at all ( i don't know)?

Anyways, this is all hypothetical, but I am really interested in hearing everyone's take on the theory. PLEASE NOTE: This is not meant to be for or against commercial or FN fisheries. It is purely a biological theory that I had and am interested in hearing what everyone thinks.

Do the earliest fish to arrive in their respecitve runs represent the top of the gene pool, and if so, should we try to avoid catching them and allow them to spawn? This would surely be a way to increase future runs, with healthier gene pools, if it is accurate.

Thanks as always,

Andrew.

[jon5hill]

Do the earliest fish to arrive in their respecitve runs represent the top of the gene pool, and if so, should we try to avoid catching them and allow them to spawn? This would surely be a way to increase future runs, with healthier gene pools, if it is accurate.

Take the Cultus lake stock complex. It is composed, just like other runs, of a range of adults that return through a range of times. No one time is necessarily better than another for spawning. Earlier may not be better for a variety of reasons. There could be an environmental catastophe like a flood that completely washes out all the eggs of the first fish that show up, making the late fish in that year the more fit. Or later fish could simply displace the eggs of the earlier fish by building deep redds and knocking the previous eggs loose. It's easy to see how no isolated timing is better than others, considering the many random events that may take place, and the variability in the environment. In this respect, a healthy run should be well represented by a whole range of spawning adults, such that in any given conditions there is a wide range of attributes available to be selected from. The analogy to a balanced stock portfolio is particularly fitting. If we wanted to avoid ruining our fish, the strategy we should be practicing is to harvest each run of fish commensurate with their contribution to the entire Fraser stock. If we take little bits from a lot of places, rather than a lot from a few places, we will maximize the genetic variation in the stock and have healthier returns in the future as the fish will be more varied in their genetics and be more able to adapt to changing environmental conditions. I hope this answers your question.

[andrew5]

really cool analogy about the varied stock portfolio, and good point about later fish displacing eggs.

My question to your "take a little bit from a lot of places" is if a 32 hour opening this week, with another one planned Monday follows that logic.

I know a lot of the commercial guys would rather have 4 eight hour openings, rather than working 32 hours straight... Those boats worked straight throught he night last night, and understandably so, withthe infrequesnt openings.

[alwaysfishn]

Using the cariboo herd as an example (it translates well to the sockeye... large group of migratory animals). All of the factors that kill off the cariboo herds during their migration (wolves, bears, climate etc) kill off the weakest of the animals, and the strongest are left to procreate after reaching the breeding grounds. Hunting, on the other hand, is often centered around harvesting the biggest, fittest percentage of the populatin, essentially decreasing the top end of the gene pool.

Your post has some interesting points however I would like to correct you on your hunting analogy. You are correct that wolves, bears, climate, etc kill off the weaker animals leaving the strongest to procreate. Wildlife management with respect to hunting tries to replicate this as well. Most areas in BC are closed to general open seasons. Most animals are harvested as a result of the hunter applying for a limited entry hunt (LEH) for a specific animal and antlered or antlerless. Wildlife authorities have an idea of success ratios and they issue only as many LEH tags as they consider are ok to sustain the wildlife. Trophy hunters do target the largest most mature animals however that is good in that many of these animals have reached maturity and many often do not survive through the winter after having participated in the rut. The younger bulls have the same good genes that the older bulls do. IN many areas there are open seasons on calf moose. The reason is that the populations are healthy and by harvesting the calf the cow has a better chance of surviving the winter because it doesn't have to look after a calf.

I don't mean to hi-jack your thread but as a hunter I wanted to make you aware that hunting is very aware of conservation and supports it as it ensures the future of hunting.  

[rhino]

I think also think that the weak are "hunted" in the ocean before they reach the spawn.

[jon5hill]

really cool analogy about the varied stock portfolio, and good point about later fish displacing eggs.

My question to your "take a little bit from a lot of places" is if a 32 hour opening this week, with another one planned Monday follows that logic.

I know a lot of the commercial guys would rather have 4 eight hour openings, rather than working 32 hours straight... Those boats worked straight throught he night last night, and understandably so, withthe infrequesnt openings.

It's likely going to sample a more varied dynamic if the harvest is spread over a few days rather than in one big clump. However management is likely banking on the diminishing returns of fishing for 32 hours straight that would reduce the overall catch than if a well rested fishing crew fished in 4 8 hour shifts, allowing the area they are harvesting from to repopulate with fish. I think a 4 day window would sample much of the same runs of fish anyway, so it may be more practical to reduce the total catch during that period rather than make it more effective over 4 days and harvest the hell out of those same runs.

[andrew5]

cudos to everyone here for some great and refreshing points.

the LEH method in hunting is a good point.

I think everyone hopes for years as good as or close to as good as this years (even though that would be impossible). How do we raise the years in between this year and every fourth year like this one? Can hatcheries do this alone?

[skaha]

cudos to everyone here for some great and refreshing points.

the LEH method in hunting is a good point.

I think everyone hopes for years as good as or close to as good as this years (even though that would be impossible). How do we raise the years in between this year and every fourth year like this one? Can hatcheries do this alone?

--why muck with nature, high low cycles different years.
--maybe the river needs a rest or other species need the space in between
--if we got to feedlot style full capacity every year we may get feedlot type diseases due to over crowding and also tending toward a mono culture with our favoured species.

--if we stack more salmon in each year it could be affecting available food in the ocean... some believe a few lean years builds up food supply thus enhancing survival on the  main run year.


--just imagine what the seal population would be if we artificially increased the salmon runs every year

[ynot]

wolves kill any caribou they can ,mostly calfs more than they can eat. wolverine follow the killing and get a free meal as do the ravens etc. most of the early run sockeyes are at or near spawning grounds and are in good shape. the big surplus is in the late summer run ,this run is at 17 mil and might be bigger than that. the water in the fraser is cooling so even 30 percent harvest would leave plenty to spawn.

[obie1fish]

How about that? a good, respectful, rational discussion involving sockeye!

Just a thought- this is being touted as the largest run of sockeye since 1913. Has anyone thought of any negative impact to such a disproportionate run? Factors might include:

-fertilization from carcasses (overfertilization?)
-spawning habitat size and limitations
-rearing habitat and food supply
-the anticipated price at the stores due to oversupply
-the already insufficient space for storage with the commercial processors
-possible increased catch limits for sporties in the ocean/river

Not to emphasize negativity, but I'm always cautious of huge windfalls, in the same way that an improperly managed lottery windfall might cause huge problems. Or the history of cod stocks from the East coast.

I highly doubt that that this year is the saviour of the sockeye runs, or that it spells doom due to overpopulation of the river by one species. Basically, I feel we need to look soberly at this season and approach the management of this year wisely.

[skaha]

--for sure all the critters that eat the sockeye should have a good survival rate which may effect next years smaller run.
--could get a disease break out in densly over populated areas
--they will displace other fish and critters that compete for the same space

--even attitude of some people has already changed.. berating those who have been concerned with recent stocking levels. Some thinking no matter what we do nature will rebound so continue the abuse. Others may think current fisheries management must be OK given the run size.

[DavidD]

This is an interesting discussion - really makes a person think about things.

... Makes me really wonder how the salmon survived all these centuries without our modern day interventions 

If we removed the human population from the equation, then nature would/could revert things back to the cyclical norms. 
As I would believe that the salmon runs had their own up and down cycles well before 'we' came along.

[StillAqua]

Fraser sockeye production was always dominated by the big three sockeye producing lake systems: Chilko, Quesnel and Shuswap. And the sockeye populations in each had a population pattern called "cyclic dominance" with a 4 year cycle (sockeye average 4 year life-spans) of a huge dominant year, a smaller sub-dominant year (about 10% of the dominant) and 2 off years of very low abundance.
Now that was okay because the big three systems had different dominant years so overall, the Fraser averaged pretty good sockeye returns most years. It was the Chilko and Quesnel dominant years that failed last year so unless the "cycle" is being reset by mother nature to new dominant years, the returns could be pretty grim for the next 3 years.