Creating your own trout stream

[sarce]

To add to Salmonoid's list, MD DNR has repeatedly called brown trout "invasive" specifically re: the Gunpowder Falls tailwater tributaries. Ironically they're the ones who opened that can of worms many decades ago and now regret it. With that said, the expansion of browns in that area at the expense of brookies also coincided with rapid urban and suburban expansion so it's not ALL due to competition between the species.

Back to the OP, this project does seem pretty awesome. I'd love to someday have the opportunity to do something similar. If water temps don't exceed 70 though, it's well within the tolerance for brookies. This summer, I was doing a monitoring project on some MD brook trout streams that have pretty good populations. Most of those streams reached between 68 and 72F every afternoon for weeks on end. While folks shouldn't fish for trout around that 68-70 degree threshold, those fish can survive it just fine if left alone.

 

[Swattie87]

afishinado wrote:

From what I've read, fishery biologists do not consider SMB an invasive species in the Susquehanna River.

You can agree or disagree, I guess.

I really don't know what data is used by them to make that determination.

Got ya.

The societal perception of SMB is arguably even more favorable than Brown Trout. As such I think, their ecosystem impacts can be more easily overlooked than other "invasive" species. Or in some ways even (angler recreation, which I enjoy them for), their presence outweighs the secondary impacts.

But my point is, we need to be asking the native Fallfish and Redbreasts if they appreciate their presence, as they're really the ones that count from a biology/ecology standpoint. (Not the subjective opinion of us anglers, or fishery biologists.) If their populations have been impacted by the presence of SMB, my compass points to the ecosystem having been impacted. I guess if someone (a fisheries biologist I guess) can objectively/scientifically quantify somehow that they (or any other native Susky species) haven't, I'm open to reconsidering my viewpoint. I struggle to think the net impact is zero, however.

 

[jifigz]

I totally agree with Swattie. If we could ask fallfish and redbreasts (both native) if they have felt the impact of smallmouths I think that the answer would be a resounding YES. Smallmouth have most definitely cut the other two species numbers down and altered the river system. Is it harmful? Probably not as far as human beings are concerned, but.......

 

[afishinado]

Here is some info defining invasive species >

The invasive species label attaches only to populations of species whose impact upon introduction has altered their new environment. Although this impact can be beneficial, the term as most often used applies to introduced species that affect the invaded habitats and bioregions adversely, causing ecological, environmental, or economic damage.

The term "invasive" is poorly defined and often very subjective, and some broaden the term to include indigenous or "native" species that have colonized natural areas. The definition of "native" is also sometimes controversial.


Link to Source > https://en.wikipedia.org/wiki/Invasive_species


Here is how species are evaluated to determine their status as invasive or not in an ecosystem. Very complex >

https://link.springer.com/article/10.1007/s10530-017-1378-4

 

[Swattie87]

^ That's a fair explanation for sure. Lots of inherent gray and room for interpretation.

My personal opinion based in present reality, not in theory, is that SMB and Brown Trout are well established at this point, and I, along with many others enjoy fishing for them. I support measures to protect and enhance their fisheries where they're already established. I don't support measures to attempt to selectively remove them where they're already the dominant sport fish species as that's counter-productive. You're not going to be able to remove enough Brown Trout from Spring Creek to re-establish Brookies there, for example...You're just going to harm the Brown Trout fishery by trying.

In areas where they are not present, or are only present on the fringe in non-fishable populations, I support measures to limit their introduction and reproduction. (No stocking, and I'd be ok with a regulation in some watersheds that allows for harvest of the odd rogue Brown Trout, but not Brook Trout for instance. Though, this admittedly gets complex and confusing for the average angler.)

Jury is still out on Snakeheads and Flatheads in my mind. I haven't personally developed an affinity for them, yet, but I know others have.

 

[afishinado]

Swattie87 wrote:
^ That's a fair explanation for sure. Lots of inherent gray and room for interpretation.

My personal opinion based in present reality, not in theory, is that SMB and Brown Trout are well established at this point, and I, along with many others enjoy fishing for them. I support measures to protect and enhance their fisheries where they're already established. I don't support measures to attempt to selectively remove them where they're already the dominant sport fish species as that's counter-productive. You're not going to be able to remove enough Brown Trout from Spring Creek to re-establish Brookies there, for example...You're just going to harm the Brown Trout fishery by trying.

In areas where they are not present, or are only present on the fringe in non-fishable populations, I support measures to limit their introduction and reproduction. (No stocking, and I'd be ok with a regulation in some watersheds that allows for harvest of the odd rogue Brown Trout, but not Brook Trout for instance. Though, this admittedly gets complex and confusing for the average angler.)

Jury is still out on Snakeheads and Flatheads in my mind. I haven't personally developed an affinity for them, yet, but I know others have.

^ Pretty much spells out my own thoughts on the subject.....+1

 

[moon1284]

salmonoid wrote:

moon1284 wrote:
I didnt watch the video. Brown trout are not an invasive species in North America throughout the vast majority of their range. They are an introduced species. I'll stand corrected if someone can cite sources from any state or federal agency that declare brown trout an invasive species.

The term invasive species is thrown around way too much. There is a difference between an invasive species and an introduced species.

I'm not an ST expert by any stretch but destruction of habitat has hurt brook trout much more than the introduction of brown trout.

When an introduced species eats the native species, it's invasive. I posted half the transcript from the video link you posted, from a federal agency. The very definition of invasive puts the brown trout under that umbrella. But please do provide your explanation for why there is a difference between an invasive species and an introduced species.

No argument from me that habitat loss hasn't helped ST in PA, but that does not negate the fact that there has been loss caused by pressure from non-native salmonids.

It's not too hard to find agencies that view browns as invasive, here and around the world.

https://www.azcentral.com/story/news/local/arizona-environment/2019/10/14/heres-how-national-park-service-plans-cut-invasive-brown-trout/3948851002/

Not specific to browns, but demonstrating the effects that the introduction of non-native trout to any environment where they were not..

https://www.fs.fed.us/research/invasive-species/fish-aquatic/nonnative-trout.php

Different side of the pond:

https://www.nies.go.jp/biodiversity/invasive/DB/detail/50180e.html

International view:

http://www.iucngisd.org/gisd/species.php?sc=78

Affects of "introduced" AKA invasive browns on ST:

https://www.usgs.gov/news/usgs-study-reveals-interactive-effects-climate-change-invasive-species-native-fish

You showed some sources so I'll stand corrected. It is still not correct to say introduced aka invasive. Unless terminology has changed since I finished college.

I guess my point is that the term invasive species has a finite definition. Lots of people believe the terms non native or introduced are synonyms for invasive. They aren't. I was a very poor college student but I majored in biology and this is one concept even I grasped. To call any non native species invasive is wrong by definition.

 

[ryansheehan]

Hate that this awesome post got sidetracked, even though the invasive species conversation is worth having.....just not in this thread.