Susquehanna study

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salvelinusfontinalis

salvelinusfontinalis

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Saw this on Facebook. Dunno how new it is but thought I'd share it here.

I thought some of you interested in the smallmouth issues might find this interesting. This is not speculation about flatheads eating too many fish, or fracking waste coming down and hurting the river. This is the extremely thorough chemical analysis of what is in the water and spawning beds of smallmouth that are seeing sexual mutations and other problems. The study concludes that agricultural runoff is a large contributing factor. All of the dominant mutation-causing chemicals found were from crops and livestock.
In this study from Dr. Blazer of the USGS, they narrowed down some chemicals that occur in high concentrations in the spawning beds, and in the water during spawning. This is called correlation. It doesn't prove that these chemicals are causing our problems, but it does show that these chemicals could be causing the problems, and that they are present in high concentrations at the time when the eggs and fry are particularly vulnerable. These are Estradiol, or female cow hormones; Tetracycline, used mostly in livestock to promote growth; and Atrazine, an herbicide used in growing corn. Here are the conclusions. The study can be purchased by searching for "Chemical contaminants in water and sediment near fish nesting sites in the Potomac River basin: Determining potential exposures to smallmouth bass".
5. Conclusions
The 135 chemicals detected in water and/or bed-sediment samples associated with active SMB nesting sites can originate from various human and animal waste sources (e.g. WWTP, septic systems, animal feeding operations, crop land). These results, in conjunction with the companion study on the biological assessment of SMB at these same sites (Blazer et al., 2012), provide weight-of-evidence that agricultural activities (e.g. crop and livestock production) are important sources of endocrine disrupting chemical exposures to SMB during critical life stages in the Potomac River basin. Such evidence includes: (1) the detection of 17alpha-estradiol (the primary form of estradiol excreted by bovine); (2) the detection of veterinary pharmaceuticals used in animal agriculture (e.g. tetracycline and sulfonamide antibiotic compounds); (3) a statistically significant relation
between dissolved atrazine concentrations in the water column above active SMB nests and TOrank; and (4) a statistically significant relation between biogenic hormone/sterol concentrations in bed sediment
associated with active SMB nests and TOrank. This corroborates previous studies in the Chesapeake Bay watershed (Ciparis et al., 2012) which conclude that a more definitive assessment of the relative contributions of contaminants from agricultural activities is key to understanding the underlying factors causing the observed adverse effects to SMB. Such understanding is critical to making scientifically defensible management decisions regarding overall fish health in the Chesapeake Bay region.
 
Thanks for posting this. All these years after the collapse of this river and all the "evidence" whether anecdotal or verified by science and nothing has changed. It's good to do the studies but we all have had a hunch for many years that all of these substances were harming the fish. I remain convinced that no amount of studies will have an effect on the actions of people who are in charge.

More water this year might be helpful.
 
Note that this study references the Potomac, not the Susky.
This is an important distinction.

Although similar river systems with agro run-off problems, bass are thriving in the Potomac watershed. They aren't thriving in the lower Susky. Why the difference?

Blazer was the speaker at the PFBC SMB summit a few years ago and her research is groundbreaking and important. Of interest however, is that her research is finding these contaminants in many river systems, not just the lower Susky where the bass crash has occurred. I think, with time, these studies will reveal such contaminants to be widespread in mid Atlantic River systems.

There is evidence that intersex characteristics may be worse in the Susky than other watersheds. . .so there may be some tipping point or threshold that has been crossed in the lower Susky.
However, it is way too early to blame these issues for the lower Susky bass crash. It may be the problem - or part of it - but the more these issues are discovered in other waterways, the weaker the link becomes to the bass problems in the lower Susky.

(Blazer's research has been discussed in many earlier threads on the Susky)
 
FI...just an observation, presence of flatheads is one difference between lower susky and Potomac. However, invasive catfish do not explain sores and lesions on fish - and you're right, farm runoff affects nearly every east coast bass river. There's something that is being overlooked, I certainly don't know what though.
 
Each waterway is different... flows, human impacts, runoff etc.
Are we finding similar concentrations in other rivers outside the Potomac? I see the Potomac has dams, but are they of similar size to the Susqy? Does the water slow down in the lakes the same? Correlation is just that. They can draw lines and make guesses, but we still don't have an answer.
Further research required! But please do continue to research... continue to make change... continue to fund stream side improvement and education!
 
Here is a thread from 6 years ago...(2009) when they Dog and pony show came to town...Its kind of amusing.

Go to wrightsville and target bass. I dare ya.

2009 Susky Harrisburg meeting
 
Maurice- the gist of it is "more study is needed"......

I was watching the river a few evenings during the huge mayfly hatch. I was at Wrightsville and south of there. SAW NO FISH RISING.

To be fair I have caught a few in that area in the spring but nothing to write home about.
 
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