Columbia researchers study intersex sturgeon in Missouri River
updated 6:54 a.m. CST, Tuesday, December 7, 2010
BY Katy Bergen

http://www.columbiamissourian.com/stories/2010/12/06/columbia-researchers-find-intersex-sturgeon-missouri-river/

COLUMBIA — Donald Tillitt was in his office at the Columbia Environmental Research Center when he received a call.

"You need to come back here and look at these," Tillitt recalls biologist and colleague Diana Papoulias saying.

[...]

When Tillitt looked inside the fish before him he saw ovarian tissue — black eggs — growing around white testicular tissue. It had the fully developed sex organs of both a male and a female sturgeon.

The Missouri River has massive run off of agricultural chemicals, and a lot of stockyards, most of those animals are given growth hormones like DES.  That fish wasn't swimming in a river as much as it was just in a chemical soup.

I read "Study intersex SURGEONS in Missouri river..."

The image in my brain was even weirder, it involved flippers, swim trunks and surgical masks...
"The surgeons swim upstream to the spawning-grounds"...
"bloop-bloop," "Swish-plop," "Ooh, a Starbucks!"

Yeah, what Tekla said-fish are really sensitive to agribusiness runoff...I also seem to remember fish downstream from paper mills being all of one gender or another, I'm wanting to say female...and fish sexing is more plastic. They swap sex in some species...If I'm remembering correctly.