Big Muddy Speaker Series presents:
Intersex Sturgeon on the Missouri River? The effects of emerging contaminants on a big river
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 endocrine disrupting chemicals.
Diana will describe 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.
This dissection of an intersex sturgeon shows both male and female reproductive tissue. photo courtesy of Diana Papoulias, USGS.
Meet Your Presenter
Diana Papoulias, PhD
, retired Research Fish Biologist
Diana Papoulias, PhD, is a retired Research Fish Biologist at the USGS Columbia Environmental Research Center. The primary focus of her study has been to investigate factors that disrupt normal developmental and reproductive processes in fishes.
Related Presentations
Resources & Links
Further research on this fascinating topic.
- Diana Papoulias, PhD, USGS – staff bio
- "Missouri River Researcher to discuss how estrogen-like compounds affect sturgeon" - by Brendon Gibbons, Columbia Missourian, July 8, 2013
- “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)
- "Effects of Endocrine Disrupters on Fish Populations" (USGS) - links to many articles and studies.
- “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)
The Big Muddy Speakers Series in Kansas City
is hosted by these wonderful partners!
- Little Blue River Watershed Coalition
- Friends of Lakeside Nature Center
- Missouri River Relief
- Healthy Rivers Partnership
- Friends of Big Muddy
- Big Muddy National Fish & Wildlife Refuge
- Kansas City Digital Video
Thanks to all of our venue hosts for making this possible! Click here for a list of upcoming presentations» The Big Muddy Speaker Series is also held monthly in Rocheport and St. Charles.
Recordings of Presentations
Kansas City Digital Video has been recording Big Muddy Speaker Series presentations. These are available on their website at this link. Some contain synchronized powerpoint presentations. We will be posting these to the archived presentation pages on bigmuddyspeakers.org. Thanks Micheal Morgan and crew for putting this important archive online! The Big Muddy Speaker Series is partially funded by the Columbia Ecological Services Field Office (USFWS) and the Mo. Dept. of Conservation.
Upcoming Presentations
Introducing the Missouri River Center for Conservation Innovation
October 13, 2026Columbia, MO
Join us for an evening with Zack Miller to learn about the Missouri River Center for Conservation Innovation.
See Event
Leave No Trace Training on the Barge
October 14, 2026St. Louis, MO
Join us for a special Big Muddy Speaker Series on the Living Lands & Waters Barge where Perry Whitaker will lead us in a Leave No Trace Training.
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Missouri River Relief: 25 Years on the Big Muddy
November 10, 2026Columbia, MO
Join us for a journey through time celebrating 25 years of Missouri River Relief's work on the Big Muddy.
See Event
Plastic Pollution, Gulf Hypoxia, and Water Quality
November 11, 2026St Charles, MO
Jennifer Wendt from MidAmerica Clean Future guides us through understanding regional water quality challenges.
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