Help On Bass Gender Determination

[Haris122]

Just been wondering if anyone can tell me how gender is determined in Black Bass. Is it one of those temperature dependent type deals, or is it a regular chromosome type deal. Also if you have any online links to reading materials on it, it would be appreciated. Thanks for any help.

[Dutch]

The only was I know of to tell is cut it open and see if it has egg sacks or sperm sacks. I've talked to biologists who say they can't tell except just prior to the spawn.

[jdmidwest]

Nature.

There has been some recent studies that Birth Control hormones from waste water is making them both male and female in the same fish. Google it or contact someone in fishery management.

[Tim Smith]

Just been wondering if anyone can tell me how gender is determined in Black Bass. Is it one of those temperature dependent type deals, or is it a regular chromosome type deal. Also if you have any online links to reading materials on it, it would be appreciated. Thanks for any help.

That's a great question.

The hormone mimics don't really accomplish a sex change in bass. They just shift the males to a more feminized type and an ineffective breeder. You can do the same thing with other species and you can also make females more masculine by exposing them to testosterone or androsterone.

Higher temperature, however, is known to shift sex ratios in fish toward more males http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002837 but I don't know if that has been tested in bass. There are ongoing concerns about how climate change might affect the reproductive potential of fish populations if the rate of change outstrips the ability of natural selection to readjust.