"Dr. Vicki Blazer, USGS Fisheries Lab, explained that one of the most complicated issues facing water quality and fish health are the myriad chemicals in the water including endocrine disruptors. These chemicals, linked to intersex abnormalities in adult fish, enter the river, since wastewater treatment plants currently do not filter them out. Dr. Blazer noted that fish respond differently to stressors and multiple chemicals can have similar effects. However, the complex mixture of chemicals in addition to environmental stressors such as nutrients, water temperature, turbidity, etc. can adversely affect fish health.
Blazer said that she has been studying smallmouth bass since 2003 and noted that there is no one cause for the fish kills seen to date but rather a perfect storm of multiple bacteria and other agents at work that collectively weaken their immunosuppression system, making them succumb. She pointed out that with young of the year smallmouth bass mortality in the Susquehanna watershed, many coinfections have been identified.
Her groundbreaking research identified that smallmouth bass’s exposure to estrogenic chemicals results in the creation of intersex fish.
Some of her Lessons Learned have included:
All fish are not created equal. They respond differently.
Aquatic organisms are exposed to complex mixtures of chemicals in addition to other environmental stressors (nutrients, temperature, etc.)
Multiple chemicals can have similar effects
Many effects such as intersex may occur early in life and not be seen until maturity.
She is now focusing much of her research on the long-term impact of these endocrine disruptors on fish health. She identified that the herbicides encountered most often include atrazine, simazine, metolochlor, fipronil, and metalyxyl. Blazer also pointed out that you have to study fish tissue since what is in the water may not provide the whole picture. Also, need to study the yolk of the egg for more data.
Her research also found that genes are being suppressed – and believes a new virus is causing the dark splotches on the fish, creating melanistic adult bass – termed “blotchy bass” syndrome. It is just odd dark tissue on the body, fins, mouth and does not appear to be precursors to the creation of lesions.
Her molecular studies work, along with the efforts of her USGS researchers, Heather Walsh, Adam Sperry, and Luke Iwanowicz, indicate they may not be looking at the right things. She noted that Metformin is one of the most commonly prescribed drugs for diabetes and was the only pharmaceutical found at all of their research sites. What role, if any, does Metformin play in impacting the smallmouth bass population.
Blazer lamented that the Chesapeake Bay Endocrine Disruption project is ending while there are still many questions that need to be answered and others that haven’t not even been asked as of yet. She believes that much more work needs to be done on how land and climate change affect fish issues and the importance of analyzing trends over time. She also believes it is critically important to assess agricultural best management practices in relation to our chemical and biological data and then to utilize this data to choose “focal sites” for more in-depth study. She closed by saying we need a better understanding of the food and parasite/pathogen web."
Jesus. The time necessary to determine the impact of all the possible variables is clearly going to be longer than the time it will take for this population to be critically impaired. If we wait to see exactly which chemicals we need to control better before enacting protections, we are going to lose our rivers. We need to take clean water seriously now, and we need to pass the sort of regulations that will protect our streams and the environments they flow through. Currently in PA, there is a bill to reclassify water pollution so that it is nearly impossible to say that someone has polluted. It will reduce compliance with regulations, and what's worse, it will delay or completely prevent mitigation or reclamation after the event, because it technically won't be a pollution event. It is (obviously) a lobbyist-written bill. Contact your local representative. I did this morning.
Over the last 2 years, many federal water protection regulations have been repealed or weakened, allowing such contaminants as coal waste and agricultural waste to be legally dumped into watersheds. The pebble mine in Alaska has been approved. Our rivers are quite literally under attack from nearly every direction, and often by those who don't realize the damage they do: developers, energy interests, municipalities, industrial concerns, farmers, our own cars and runoff from our yards (think Roundup) and streets, and of course, still the classics of AMD and PCB contamination from our historical stupidity.
We need to start taking this stuff seriously and voting on this issue if we want to be able to enjoy the sport we love years from now, regardless of which party controls the federal government. We need to get the contaminants out of our water, whether that means tighter regulations on industry, better filtration systems for waste water, or other efforts that may result in expense and inconvenience. If and when these rivers finally give up their ghosts (like the Susky appeared to have done for most of a decade), most of us won't live long enough to enjoy their rebound, if they have one. For the life of me, I will never understand the lack of political will to simply protect our air and water for the overall health of the environment.
