What's your opinion of the current state of our fishery?

[Yankee Troller]

12 hours ago, HB2 said:

I just looked at the Canadian summer derby results for this year . Their sizes were comparable to ours . I know every once in a while I see one that's maybe 35 # . That's not a whole lot bigger than our biggest derby winners . 

 

Caught some nice skien under a float kings this afternoon . Man do those fish fight . Amazes me the power these zombie fish have . 

 

 

 

 

 

You need to dig a little deeper. Their board get zeroed every week for about 8 weeks and each week their board will beat our Summer long (about a month) derby leaderboard.

[rolmops]

3 hours ago, LongLine said:

The lengths of 3 year old Chinook salmon have been getting shorter and shorter over the years.  More and more have spawned earlier in their life cycle. This has been happening on the west coast also. All the food in the world isn't going to make them longer.  Food makes them fatter.  If food made a person taller, more muscular, live longer, then an awful lot of people would be 9 ft tall, be built like Mr. America and live well over 100.
 

It takes reasonably tall parentage to have tall kids.

That sounds nice ,but you disregard genetic potential under ideal circumstances. Plentiful food will increase the chance of a fish to reach its genetic potential, specially if the food has a high protein content like most alewives do.

[LongLine]

Looking at the 3 LOC's, there's only one over 30 and that was 31.

 

Genetic potential and genetic reality are two different things.  For years there has been a downward trend in the length of 3 yr olds per DEC.  Something is stunting their growth.  This is also happening on the west coast. Proteins are great for building muscle mass, but I've never seen anything to say they make one taller/longer. 

 

But the big question to me is why are the reaching sexual maturity at a younger age? 

[Jm1984]

I think it comes down to selection both natural and influenced has selected for the smaller fish to have “greater” reproductive success.   If smaller fish are able to tolerate warmer water than larger matures, in theory they would be able to better deal with running the tribe under a variety of conditions.  Then if you look at fishing pressure and the associated harvest selection bias of bigger is better, the larger matures would be disproportionately targeted by angling pressure.  So if this continued for a number of years then in theory the average size of the fish would decrease because more and more smaller fish are achieving success in spawning and passing along those genetics.

[schreckstoff]

This thread is awesome. Lots of interesting ideas. 
 

How about density or in this case density dependent individual size? Across every fish species & population I have ever worked on I can not think of any that do not get smaller when density goes up and get bigger when density goes down. Alewife in LO is a great example, higher density, growth and size decline relative to when density is lower. This happened when the lake had a phosphorus concentration of 20 ug/L AND when it was 5 ug/L. Food and genetics definitely have an effect at times, but density seems to be a consistent driver of fish size
 

Just another factor to think about!

[Gill-T]

Just a snapshot in a three month-long run but look at all of the 12-14 lbers. Perhaps the answer is not the bigs get ripped out (no fishing on the Ganny during most of the run) but maybe only the smalls can jump into the raceway at the Corbett Dam?  
 

 

[Jm1984]

This is the first year that the Ganny hasn’t had fishing during the run.  Previously, it was shoulder and shoulder for the entire run.  It was the most heavily fished of the Northshore tributaries.  From all of the data that everybody is talking about here this has been ongoing for sometime. It’s not like we’ve gone from seeing 40 pounders consistently to all of a sudden this year barely seeing anything over 30.  It’s likely something that has multiple facets.  I think next year’s mature class is going to really give us a better indication as to which way the fishery is going.

 

 

[LongLine]

I can accept the density/size correlation for some fish.  The smallmouth population took a major dive a few years ago (thanks to gobies and birds) and fewer smallmouths are caught today but are much bigger than before the dive.  Also, I remember years ago the pike population in I-bay took a dive and the bay became crowed with small perch.  Now, most pike, if caught, there are in the 10-15 Lb class and perch have been reported as getting bigger.  

 

However, these fish are basically "home bodies."  I.E. they inhabit a certain area.  Chinooks are known as pelagic wanderers and not "home bodies."  So, I'm not sure the same correlation holds true for them.  Smaller Chinooks are spawning on the west coast also.

 

It's my understanding that the Chinook favorite alewife are relatively poor swimmers whose general movement is from deep to shallow water and back again. I'm not aware of any great east-west movement for them like Chinooks. (Please correct me if that's wrong)    

 

I'm not a "fish psychologist" but my question is why would an Oswego Chinook swim to Toronto when there's plenty of easy food, much closer, along the south shore to eat?  He's been called an "eating machine."  Alewife numbers seem to be rebounding.

 

Years ago, the gov't instituted a slot limit on Lakers to protect their spawners. They lowered the limit on Steelhead/Rainbows to protect the specie.  There is a minimum size limit of Chinooks and Steelhead/Rainbows. I don't see any reason they can't institute some kind of maximum size limit on Chinooks, for both open water & tribs, even if only on an experimental basis.  I.E. Can only harvest one over 33". 

[Gill-T]

?? Taking out only the biggest fish would make for smaller fish size.  Artificial selection at the hand of man. 

[Jm1984]

If you read it more carefully, he’s not suggesting only harvest fish over 33 inches he suggesting limit  limit the harvest to only one fish over 33 inches. 

[Gill-T]

Yep 👍 I can read. 

[HB2]

48 minutes ago, LongLine said:

I dont see any reason they can't institute some kind of maximum size limit on Chinooks, for both open water & tribs, even if only on an experimental basis.  I.E. Can only harvest one over 33". 

 

Sorry LL , I don't see that going over very big with the charter and especially tournament guys . 

 

 

[LongLine]

I got the general feeling that the majority of fishermen prefer the larger Chinooks.  The object is to help protect the larger fish so they can return to the rivers.  Theory being that larger fish produce larger offspring.    The regulation I would propose is in addition to the existing individual daily 3 in combination rule.  It would apply to both Open water and Tribs.  All Derbies/tournaments require that only legal fish be entered.  I picked 33" as that's a little longer than the typical 3 yr old return at the SR. (maybe should be 34" ?)
 

[Gill-T]

Maybe electromagnetic genetic alteration would help?  Great light show tonight. Cheers!

[GAMBLER]

20 hours ago, schreckstoff said:

This thread is awesome. Lots of interesting ideas. 
 

How about density or in this case density dependent individual size? Across every fish species & population I have ever worked on I can not think of any that do not get smaller when density goes up and get bigger when density goes down. Alewife in LO is a great example, higher density, growth and size decline relative to when density is lower. This happened when the lake had a phosphorus concentration of 20 ug/L AND when it was 5 ug/L. Food and genetics definitely have an effect at times, but density seems to be a consistent driver of fish size
 

Just another factor to think about!

How come the kings were bigger in the 80;s when the bait biomass density was huge?  Alewife health?  Less smelt?

[rolmops]

As to why fish are getting smaller and reach sexual maturity earlier?

There is some research that points to endocrine disrupting chemicals like BPA  which is a chemical that mimics estrogen and is often used in plastic production. We all know that huge amounts of plastic ends up in our water. But Gator would have more of a background  on that subject so I'm just throwing it out there.

[HB2]

Are we sure that these fish are sexually maturing as 2 year olds more than in the past ? Or are we mistaking smaller 3 year old kings for 2 year olds ? 

 

A few years back we were getting a lot of Jacks skien fishing .This year non so  no far and I have landed so very good size fish . 

[LongLine]

Yep.  DEC data shows they're getting smaller.

 

Grab a couple beers and read thru this:

Recent declines in salmon body size impact ecosystems and fisheries | Nature Communications

 

If you make it thru that and want more just google: "salmon maturity trends."  You'll see that it's happening to all salmon specie world-wide but most drastically on Chinooks.  

[jeb1340]

I can remember in the 80s the huge smelt runs in the Niagara. It’s nothing like it used to be. I wonder how much of their diet then was smelt? Also nutritional value of smelt vs alewife? My other thought was the amount of bait throughout the year that was available. Were they able to feed more consistently year round? 

[LongLine]

If you look at the 2022 DEC L.O. Annual report under Characteristics of the salmon run on the SR, they note the Chinook run consisted of 54% 3 yr olds and 39% 2 yr olds.  Although they calculated 4 yr olds to be only 1%, there are no physical measurements of any 4 yr old.  Back in the 80-90's there were up to 10% 4 yr olds.   

 

So, to Yank's point: yes, eggs & milt should only be taken from the largest fish and IMO something should be done to protect some of the larger ones.  

[Sweet Caroline]

A few  thoughts:

1. Regardless of the age make up of mature fish that are in the system, are 2, 3 4 yr olds smaller now then they were 10-20-30 years ago? Seems like LO chinooks are maturing earlier,  but there is still enough of a sample to determine if the same age fish now are actually smaller then they were back then. 
2. I don’t think that just because a salmon is caught in Canada means it was hatched in Canada, unless it was caught in or near a river in the Fall. Most of those large tourney fish were caught in the Summer months when Salmon are still wandering all over the lake. I think tagging studies clearly showed that salmon travel up and down and back and forth all over the lake up until they start honing in on their spawning streams late Summer and Fall. They travel thousands of miles in the ocean. LO is a fish bowl compared to that. I think a better test would be to see if the mature fish in the stream are larger in Canada then on our side. This way you pretty much know they were hatched there. 
3. To determine if it is a bait or over population issue a good test 

would be to  greatly reduce or stop stocking to see if size increases. I’m sure nobody wants to do that nor do I.  I believe Lake Michigan did do that to a certain extent and did see a size increase. 
4. I don’t think the cherry picking of large fish by fishermen on the salmon River before they make it to the hatchery has a major impact. Salmon move quite a bit at night and many still make it. Based on the amount of salmon I see at the hatchery it would seem hard to believe that there are no big boys that make it through the gauntlet. 
5. From a pure logical perspective it would seem to be a no brainer to collect as many eggs and milt as you can from the largest fish that make it to the hatchery. Large parents usually have large kids, 

All this just my opinion of course. Nice, healthy debate fellas and an interesting read. 

Edited October 12 by Sweet Caroline

[Kingme2Go]

Good discussion. Above is the full series of age structure of Chinook in the hatchery referenced. Seems like proportion of age 2 kings has gone up and down in the hatchery in 5-10 year periods.  Proportion of age 1 jacks is currently way down. Age 4s was up to about 10% in 2020.  It's tough to make a case for a trend or evolution towards earlier maturity. Maybe other factors at play?

[Gator]

As per Rolmops, sh$t gets crazy when you starting throwing in endocrine disruptors. There's simply not enough data to say that they're having an effect in Lady O's salmon but we know that trans-generational effects of environment inputs are routine in nature, even disregarding endocrine disruptors. For example, parental starvation can elicit metabolic changes in progeny for several generations. Similarly, one of our recent Alzheimer's models appears to have a sterility phenotype that depends on how much toxic protein the parents expressed and how old they were when giving birth. We don't study BPA, but the idea is the same. Scary stuff.

 

Anyway, lots of variables at play, of which this may be one. I'm still on board with the fishing this past year though! 30 lb fish seem like too much work for me now lol.

[LongLine]

"Evolution" may explain what's happen to salmon world- wide but doesn't explain reported differences between US and Canadian Kings. 

 

The problem with research is that for every question answered, many more questions spring up.

 

Browsing thru the 2017 L.O. Annual report (Sec.3) there is significantly greater straying by direct stocked Kings than by pen reared Kings.  Direct stocked greatly returned to the SR, although some Pen reared did. The objective of the pen rearing is to get the kings to return to those pen sites.

 

In same publication (Sec.1 A-13) there is a table showing the weights of the pen reared kings for a number of years.  From 2005-2016 the average weight of DEC SF pen reared kings was 6.2g.  For same years, OMNR SF pen reared was 7.7g. (24% bigger)

 

Browsing the 2022 L.O. Annual report: Almost 600K SF Kings (DEC) were pen reared out of 904K Kings stocked.  The average weight calculated to 6.9g.

 

The questions I have include: Does this weight difference explain some of the weight differences reported as adult fish?  Why is there a weight difference between DEC & OMNR SF fish?  Should the SF Kings be kept at hatchery or in the pens a little longer?  

[Jm1984]

I can offer a bit of insight on the Ontario pen project numbers, there is a couple of locations that skew that weigh up.  The harbours there have active flowing creeks that feed them and wash a lot of food into the net pen area.  These locations average a 1 to 1.5 gram higher average weight every year.   The location that I help with has average numbers inline with the US average.