Big Muddy Speaker Series presents:
Intersex Sturgeon on the Missouri River?


Presentation by – Diana Papoulias, PhD, Research Fish Biologist – US Geological Survey Columbia Environmental Research Center
Original Presentations:
- Tuesday, July 9, 2013, at Les Bourgeois Bistro in Rocheport, MO
- Tuesday, October 28, 2014, at Healthy Rivers Partnership Office, Kansas City, MO
- Click here to watch a video of Diana’s presentation recorded by KCDV.
- 7-9-13_dianapapoulias_intersexsturgeon
In 2000, research fish biologist Diana Papoulias began documenting an uptick in previously rare cases of intersex shovelnose sturgeon. These Missouri River fish were developing both male and female reproductive organs.
Those fish were shovelnose sturgeon, which are considered a valid experimental surrogate for the federally endangered pallid sturgeon. Diana's discovery began more than a decade of research into this phenomena, focusing on finding the chemical and environmental causes that are present in Missouri River water that might be effecting the reproduction of the pallid.
This research has been ongoing during a period when a lot of research into "emerging contaminants" in our water supply has shown disturbing effects of phyto-estrogen compounds and other endocrine disrupting chemicals.
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This dissection of an intersex sturgeon shows both male and female reproductive tissue. photo courtesy of Diana Papoulias, USGS.
- Diana described the reproductive effects they've documented in fish, what is known about the chemical contaminants in the Missouri River, and the pathways for how these chemicals are causing such dramatic changes in fish.
Meet Your Presenter

Diana Papoulias, PhD
, Research Fish Biologist, US Geological Survey Columbia Environmental Research Center
Diana Papoulias, PhD, is a Research Fish Biologist at the USGS Columbia Environmental Research Center. The primary focus of her study is to investigate factors that disrupt normal developmental and reproductive processes in fishes.
Related Presentations
Resources & Links
- "Columbia Researchers Study Intersex Sturgeon in Missouri River" - by Katy Bergen, Columbia Missourian, Dec. 6, 2010
- "Feminized Fish: A Side Effect of Emerging Contaminants" (audio - Sept. 6, 2012, KAOW)
- FAQs on endocrine disrupting chemicals (EnToxNet)
- "Emerging Contaminants in the Environment" (USGS) - a wealth of links to articles and studies.
- "Endocrine Disruption" (USGS) - links to articles and studies.
- "Estrogen in Waterways Worse than Thought" (by Allison Winter, Scientific American - June 4, 2009)
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