Bug question for Mudwall...

[flatlander]

Something I've often wondered about:

How easily can bug populations migrate from river to river?  Specifically, could the Holston ever hold the Watauga's caddis hatch/population?  I assume most of the bug species currently in the Holston weren't present before the dam--is that correct? 

[snagaluffaguss]

I'm not Mudwall but Id like to take a stab at this one if he and you don't mind,


Bugs will be where they will be. 

That is to say,  like all animals, if a habitat or niche exists there will usually be an animal (or bug) to fill it.  If the Holston has lesser caddis hatches than the Watauga then the most likely scenario is the the habitat (bottom structure of the river, or the amount or type of detritus) is much different than that of the Watauga, and more likely suited to the preferences of the Ephemerella genus of mayflies than those of say Brachycentrus genus of caddis.


This is of course an uneducated guess.  I am curious to hear more.

[flatlander]

I'm not Mudwall but Id like to take a stab at this one if he and you don't mind,


Bugs will be where they will be. 

That is to say,  like all animals, if a habitat or niche exists there will usually be an animal (or bug) to fill it.  If the Holston has lesser caddis hatches than the Watauga then the most likely scenario is the the habitat (bottom structure of the river, or the amount or type of detritus) is much different than that of the Watauga, and more likely suited to the preferences of the Ephemerella genus of mayflies than those of say Brachycentrus genus of caddis.


This is of course an uneducated guess.  I am curious to hear more.

Snag,
I think you're probably right and I've considered that as a possibility.  The Holston has caddis populations...just not fishable hatches of them (at least I've never seen a fishable caddis hatch there).  The black caddis seem to be there in good numbers, but they must hatch at night because I see them in big numbers in the bushes along the river, but never see them hatch in significant numbers.

Forget the caddis example...I guess my real question is how easily do the various hatches migrate, especially to tailwaters...and how long does it take a population to become established in numbers that matter as a fishable hatch?

[Mudwall Gatewood 3.0]

What Snags said plus water chemistry.  In addition with tailwaters, the tributaries likely play a role in what settles in and makes a go of it.  I believe the Watuaga has more freestone tribs than the SOHO, and I might be mistaken but I think the Watuaga acts more like a tailwater/ freestone hybrid than it does an exclusive tailwater.  And that rich VA limestone water feeding the SOHO is perhaps a bit different than the nearby Watuaga system. 

Eventually these artificial systems will reach equilibrium, and it is what it is, with little or no change unless there's some sort of perturbation or other change in the system (like building a labyrinth dam).  Using the Jackson tailwater as an example, I am not sure that system has reached stability when it comes to the critters.  I have no idea how long it will take.

[flatlander]

What Snags said plus water chemistry.  In addition with tailwaters, the tributaries likely play a role in what settles in and makes a go of it.  I believe the Watuaga has more freestone tribs than the SOHO, and I might be mistaken but I think the Watuaga acts more like a tailwater/ freestone hybrid than it does an exclusive tailwater.  And that rich VA limestone water feeding the SOHO is perhaps a bit different than the nearby Watuaga system. 

Eventually these artificial systems will reach equilibrium, and it is what it is, with little or no change unless there's some sort of perturbation or other change in the system (like building a labyrinth dam).  Using the Jackson tailwater as an example, I am not sure that system has reached stability when it comes to the critters.  I have no idea how long it will take.

Thanks.  So the populations are essentially static once they reach equilibrium. 

[Mudwall Gatewood 3.0]

Flats, densities may ebb and flow, but the players will likely stay the same. 

[flatlander]

Thanks Mudwall...I had hoped there might be room for improvement

[OldDominionAngler]

Oh so many "Bug questions for Muddy" threads too choose from.........this one was selected at random.

What ya got Mud?  Caught him sipping beer in my brother's backyard.  There is no water within sight of his house. 

[Mudwall Gatewood 3.0]

Oh so many "Bug questions for Muddy" threads too choose from.........this one was selected at random.

What ya got Mud?  Caught him sipping beer in my brother's backyard.  There is no water within sight of his house. 

A flat headed mayfly adult (some "cahill" type, Heptageniidae).  They (aquatic insect adults) will travel some distance from their home water – some types farther than others. 

Nice critter photo.