Beel den Stormer Presents the Only Fishery Blog You Need

Fish, Fisheries and Queryomics

Sexual Confusion in Smallmouth Bass

feminized smallmouth bassSexually confused smallmouth bass.  (Photo by Joel Sartore, National Geographic)

A recent article in National Geographic reports that 60 to 100% of smallmouth bass in 19 northeastern United States wildlife refuges have sexual identity issues.  Largemouth bass, a related species, also has its share of issues, with 0 to 100% fish registering as confused. The article is based on a scientific paper by L. R. Iwanowicza and colleagues (2016).

The confused males, technically intersex individuals, have eggs in their testes.  Scientists are pretty sure they weren’t put there by bass anglers.  But Beel?  Maybe not so sure.

The misplaced eggs presumably are the result of the fish being exposed to pollutants in the water that mimic the effects of estrogen, which leads to feminization.  So, its something in the water.  People drink water.  Could it be that…


Makes Beel wonder.



L. R. Iwanowicza and colleagues. 2016. Evidence of estrogenic endocrine disruption in smallmouth and largemouth bass inhabiting Northeast U.S. national wildlife refuge waters: A reconnaissance study. Ecotoxicology and Environmental Safety 124:50–59.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: