Getting Mostly Female Frys?

[blue_ram]

In many reptiles and amphibians, the temperature influences the gender of the brood (another problem with the global warming). Are bettas affected by the temperature as well? Or are they affected by something else?

 

[wuvmybetta]

They say PH alters the sex ratio, although personally I've never had it happen. Temperature could very well play a factor as well, although I've spawned in many different temps and the ratio of half and half is always the same.

What are some of your ratios? How many females are you getting?

 

[Synirr]

I think extreme temps actually do play a role. I had a spawn that I split between one tank indoors and two outdoors in the storage room of the garage. There were noticeably more females in the outdoor tanks than the indoor one (60-65%, maybe?) That was with temps in the 90s outside; the house is air conditioned and the indoor tank was at about 80 degrees.

 

[wuvmybetta]

http/www.ibcbettas.org/StadBylawsForms/S...nt1999-2003.pdf

Page 14
They lost me at "induced spawning", break it down for me, Synirr
(by the way,that link is awesome! I found it in my faves)

 

[nashnut]

My last spawn was at 82 and I had a very high ratio of males to females.

 

[Synirr]

Hmm, that's interesting in that link about eye preference... I hadn't thought about it before, but all my guys do display with their right side facing the perceived opponent.

I don't think the temp thing has anything to do with sex ratios, just average age of maturity and fertility
Someone ought to suggest an experiment dealing with environmental factors and sex ratios

 

[blue_ram]

Thanks everyone for your input. I wanted to breed one of my bettas, but didn't want to get into dozens of 1/2gallon jars. I was thinking, if I can get mostly females out of the brood, then I can keep most of them in my main aquarium, once they grow out of rearing tank. I guess I'll have to experiment with increased temperature (possibly pH as well) next spring when temp. gets to 90s...

BTW, wuvmybetta, great article. I'll have to read it over. Thanks.