Susquehanna River smallmouth bass disease identified

[raftman]

Pretty interesting article concerning the smallmouth bass population on the Susquehanna River. It sounds like they've pinpointed the reason for the drop in population in 2005 - largemouth bass virus.


https://adventures.everybodyshops.com/susquehanna-river-smallmouth/

 

[wildtrout2]

Interesting information. Thanks for sharing that.

 

[TJones]

Wow, thanks for sharing!

 

[jifigz]

It is funny what was once touted as basically a fact has all of the sudden been upended (or so the article seems to suggest) and now is the "culprit." I'm not saying that LMBV is not to blame, it is just funny how a source that was all ready known about was just never given more consideration because we thought that we knew what we knew.

I used to like to read your blog TJones! It would be cool if you still kept up with it.

 

[Dave_W]

Thanks for the link - interesting stuff.

I'm still skeptical and doubt that the Susky's problems have been definitively identified. As others have pointed out, the presence of LBV has ben known for years. However the link between LBV, hot summer water temps, and SMB mortality adds sigificant knowledge to this problem.

Also, the speculation that the bass population has developed immunity and that this explains the recovery is even more interesting.

(This thread will move to the Warmwater forum shortly - thanks. DW)

 

[afishinado]

There is science behind the study of LMB virus and its role in the mortality of SMB in the Susquehanna and Juniata Rivers in 2005.

Here is the actual study:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5834888/

The die-of was widespread and not isolated to one area with some sort of pollution source. Given all the factors and conditions at work at the time, and the fact that the study proved fish mortality can be the result under those conditions, it seems to add up that the LMB virus was a key element in the die-off on the rivers.

 

[troutbert]

The article says that warm water temperatures play a very large role in the development of this bacteria and therefore the die-off.

And many people discussed clear back in 2005 that the warm water was probably a causative factor, even if the specific bacteria wasn't yet known.

This indicates a course of action to improving the situation.

On a hot summer day, every tributary in the Susquehanna drainage has an influence on the water temp in the river.

As you travel around, notice how many streams do not have forested riparian buffers, so are getting solar heated.

 

[raftman]

Good points troutbert. Warm water discharges from places like Brunner Island certainly can't help either.

 

[jifigz]

The article also pointed out that the warm waters were one reason for the fantastic fishery. It also makes sense why the regulations they put in place years ago was only from Port Royal on the Juniata down. I have never ever recorded 90° water temps up here where I live. I'd say the summer average is generally 78°

 

[afishinado]

I looked back at the levels and temps from 2005. The Susky flow was at near record low levels and water temps soared into the high 80's to 90's for a prolonged period.

Just as a reference, the Susky at H-burg is running at 40,000cfs right now. In the summer of 2005, it hit 4,000 cfs (see below)

 

[fritz]

Pre cooling towers, Brunner Island temperature rise river inlet to discharge would have been in the 25F range all depending on conditions. Cooling towers have been in operation now for the last seven years or so.

 

[raftman]

Thanks for the info fritz!