brook trout genetics

[nymphingmaniac]

I hope this long link works. From PSU news


https://news.psu.edu/story/537280/2018/09/18/research/few-hatchery-brook-trout-genes-present-pa-watershed-wild-fish

 

[lycoflyfisher]

I heard Shannon present this research at a TU chapter meeting. The biggest question she posed and I believe deserves the most thought is "How much introgression is too much?"

 

[afishinado]

lycoflyfisher wrote:
I heard Shannon present this research at a TU chapter meeting. The biggest question she posed and I believe deserves the most thought is "How much introgression is too much?"

Easy answer, for me....any (is too much).

I never had a clue why the PFBC has and continues to stock brook trout in this State. There's really no reason at all, that's what nonnative bows and browns are for.....

 

[troutbert]

"Supplementing wild populations with captive-raised fish increases angling opportunities..."

Oh? Some people think so.

Note that that statement didn't come from any of the researchers.

 

[lycoflyfisher]

In the posted article it actually says that the statement quoted by troutbert was pointed out by White ie Shannon White who did the research. I think most if not all will agree that stocking over wild populations is bad, however stocking has had and still has merits at increasing fishing opportunities in many locations.

The most interesting point I thought she made in her presentation I saw in person, was it was evident that stocked trout were moving all over the watershed. The question was whether they moved on their own or if fishermen helped them along.

 

[afishinado]

My take from the whole thing is a concern for the genetic component of native brook trout. Stocking brook trout can open the door to intermixing genes with our native brook trout. Stocking non-natives like rainbows or brown trout may allow them to overtake natives in certain streams, but does not threaten to change the gene pool of our native fish.

 

[troutbert]

lycoflyfisher wrote:
In the posted article it actually says that the statement quoted by troutbert was pointed out by White ie Shannon White who did the research.

You are right. Good catch.

-------------------------------
Supplementing wild populations with captive-raised fish increases angling opportunities and has occurred in Pennsylvania for more than a century, White pointed out.
-------------------------------

It's interesting that this was attributed to her, but it was not put in quotes.

Numerous other statements by her were put in quotes.

Either way, it's a disappointing statement. Ending stocking over native brook trout and stocking those hatchery trout on other streams would increase angling opportunities.

The brook trout populations would increase. And the non-wild trout streams would get more stocked fish.

Stocking hatchery trout over brook trout actually DECREASES fishing opportunities. It decreases the brook trout populations, and it decreases the number of trout available in streams like Pine, Kettle, Tionesta Creek, Wissahickon Creek and many, many others.

 

[troutbert]

Can anyone place the stream stretch of that first photo, that says Loyalsock Creek?

 

[troutbert]

lycoflyfisher wrote:

The most interesting point I thought she made in her presentation I saw in person, was it was evident that stocked trout were moving all over the watershed. The question was whether they moved on their own or if fishermen helped them along.

The Sock gets very warm in the summer, so the stocked trout run from the Sock up the tributaries.

Also, there are numerous tribs stocked by the PFBC.

And there are some stockings done other people, either clubs or individuals, in places not stocked by the PFBC.

For example, someone stocks trout in the Loyalsock at the Route 220 bridge at Ringdale.

 

[salmonoid]

troutbert wrote:
Can anyone place the stream stretch of that first photo, that says Loyalsock Creek?

I think it is not labeled properly. It looks like the first big pool on Double Run in Worlds End State Park.

 

[troutbert]

Thanks. I agree that it's probably one of the tribs.

Looks too narrow for Loyalsock Creek.

 

[CRB]

troutbert wrote:

lycoflyfisher wrote:
In the posted article it actually says that the statement quoted by troutbert was pointed out by White ie Shannon White who did the research.

You are right. Good catch.

-------------------------------
Supplementing wild populations with captive-raised fish increases angling opportunities and has occurred in Pennsylvania for more than a century, White pointed out.
-------------------------------

It's interesting that this was attributed to her, but it was not put in quotes.

Numerous other statements by her were put in quotes.

Either way, it's a disappointing statement. Ending stocking over native brook trout and stocking those hatchery trout on other streams would increase angling opportunities.

The brook trout populations would increase. And the non-wild trout streams would get more stocked fish.

Stocking hatchery trout over brook trout actually DECREASES fishing opportunities. It decreases the brook trout populations, and it decreases the number of trout available in streams like Pine, Kettle, Tionesta Creek, Wissahickon Creek and many, many others.

Very good point.

 

[KenU]

Shannon White’s paper also puts to rest the myth that PA’s brook trout were extirpated early in the 20th century and then replaced by brookies from NY, NJ, WV, etc.

 

[troutbert]

KenU wrote:
Shannon White’s paper also puts to rest the myth that PA’s brook trout were extirpated early in the 20th century and then replaced by brookies from NY, NJ, WV, etc.

Exactly. That myth has been posted on paflyfish.com quite a bit.

I remember first reading that myth in a small, outdoors magazine/newsletter published by some guy in upstate PA, in the early 1990s.

I thought it was baloney back then, and have ever since. The historical record doesn't support it. And there has never been any scientific evidence for it.

This study and the NJ study show that it was just bosh, pure rubbish.

So why do people push this theory? Because they fear the possible effects of fisheries management changes if brook trout are given special status as the native salmonid in our streams.

So they fabricate a narrative, creating fake history and fake science in order to support their particular fisheries management preferences.

Instead of starting with the facts and working forward to conclusions based on the facts, they work the opposite way.

They start out with the type of fisheries management they want, then fabricate "facts" to support that.

 

[Acristickid]

Attended this presentation earlier this year-

I thought that one of the tribs would be cooler because it was heavily shaded by pines and therefore harbor more trout at least in the summer. She said that was not necessarily the case, while water temps could be cooler, the soil and trees provided lesser water quality and did not have a higher population.

 

[lycoflyfisher]

Acristickid, Not sure which trib you may be talking about but some of the tribs in the area of Shannon's study experience acid deposition issues due to extremely low buffering capacity of the bedrock in those particular drainages this can lead to very little production of food and hence those streams not supporting large populations of trout year round. They may very well be used for spawning and thermal refuge however.

 

[KenU]

Why we stock: "Supplementing wild populations with captive-raised fish increases angling opportunities...” according to Troutbert. In other words, in order to provide trout for anglers in larger sizes and in greater numbers than Nature can produce. And now the environmental effects and economic consequences are becoming obvious.

 

[afishinado]

Why we stock: "Supplementing wild populations with captive-raised fish increases angling opportunities...” according to Troutbert. In other words, in order to provide trout for anglers in larger sizes and in greater numbers than Nature can produce. And now the environmental effects and economic consequences are becoming obvious.

Ken,

Troutbert was actually quoting the article with the statement > "Supplementing wild populations with captive-raised fish increases angling opportunities...”

This quote should not be attributed to him. In fact, I believe it's safe to say his opinion is 180* counter to this statement since he's a wild trout advocate through and through.

I'm confident he will check in at some point and clarify, but in the meantime, I did not want an incorrect the statement to stand as is. Carry on.

 

[troutbert]

lycoflyfisher wrote:
Acristickid, Not sure which trib you may be talking about but some of the tribs in the area of Shannon's study experience acid deposition issues due to extremely low buffering capacity of the bedrock in those particular drainages this can lead to very little production of food and hence those streams not supporting large populations of trout year round. They may very well be used for spawning and thermal refuge however.

I also don't know which trib you are referring to.

But lyco is right. Some tribs in the Sock drainage are more fertile than others, which affects the amount of trout they can support.

Also, the physical habitat of the streams plays a large factor. If there are good quantities of pools and overhead cover, the trout population will be higher than if the stream is mostly flat and shallow. And there is a lot of flat, shallow stream habitat in the watershed due to numerous disturbances.

Also, a great many of the tribs, with a large stream mileage, stay cold enough to support wild trout within the Sock watershed. That isn't something specific to one trib.

 

[troutbert]

afishinado wrote:

Why we stock: "Supplementing wild populations with captive-raised fish increases angling opportunities...” according to Troutbert. In other words, in order to provide trout for anglers in larger sizes and in greater numbers than Nature can produce. And now the environmental effects and economic consequences are becoming obvious.

Ken,

Troutbert was actually quoting the article with the statement > "Supplementing wild populations with captive-raised fish increases angling opportunities...”

This quote should not be attributed to him. In fact, I believe it's safe to say his opinion is 180* counter to this statement since he's a wild trout advocate through and through.

I'm confident he will check in at some point and clarify, but in the meantime, I did not want an incorrect the statement to stand as is. Carry on.

Yes, I was quoting a statement from the article.

Then attacking it.