All female guppy fry, dangit!

[saram521]

I kept the mother of these fry in a 5g for about 2 weeks before she gave birth. The 5g felt like it was heated to maybe 73-74F (even though I had a brand new stealth 25w heater set to 77!) and I'm wondering if the temp. had anything to do with the babies being all female. I've tried finding info on this subject to either confirm or deny my thought that temp. affects sex ratios of guppy fry, but haven't really found anything yet. I know temp. affects sex ratios of other animals' babies, but I'm curious about guppies specifically. By the way, would anyone be interested in purchasing pre-hit female guppies? If not, I don't know what I'm gonna do with 50 females!

 

[bluekrissyspike]

how old are the fry? they all look the same when they are born. the males start to grow their fins when they are a bit older. it will be hard to sex them in the six weeks or so, and even longer for some males.

 

[saram521]

They're about 5 weeks old. I'm certain they're all female. I can clearly see the set of small pectoral fins and the one fan shaped anal fin on every single fry. Can't pick out a gonopodium at all...

 

[Dangerdoll]

eh, I would give it a little longer, you would be surprised at how they change even this late.

 

[saram521]

I hope some of them do change! The mother passed on shortly after giving birth. I thought she was a pretty gal. I was hoping to get some males from her, at least one...

 

[Squeakfish]

A higher temperature usually yields more females. The reverse is true for males.
Play with a temp a bit and you might get males.

 

[paperdragon]

5 weeks is far too young to tell by fin shape in my experience. Mine don't develop gonopodiums until at least 2 months.

 

[saram521]

I read in a popular fish mag that males will sexually mature at 3 weeks, but females will mature at 2 months. I've also read on websites where fry can take longer to sexually mature depending on what strain they're from. I'll wait longer though and hope for some males!

 

[ctbestfisherman]

I have wild-type guppies and they mature pretty fast. I was happy that 12 guppies out of 14 off mine were female so I could breed them with my magnificant male. Can you see their gravid spots? Even if they are not pregnant you should still be able to it even at 5 weeks.

 

[jpappy789]

I would wait longer to write them off as all females.