Many upper jaws are in shallow water. So, many are caught as juveniles anyways. Still one of the rarest ones to obtain. Otherwise, they'd be everywhere at the LFS and not 100-130 dollars each! lol
How many male poly do you have ?
- Thread starter jaws7777
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Regarding Captive bred poly ratio of female vs. males. It likely be due to heavy inbreeding. I believe it's either reptiles or certain mammals that several scientific studies have shown more females are produced. I would have to look it up, but it's not poly related. So I won't do it 
Its kinda like the how many licks does it take to get to the center of a tootsie pop.......the world may never know.
Totally didn't know there were low males! So many questions now!
There's a number of factors which come in to play as to why there are less males than females in the trade.
If farms are breeding the Bichirs in a pH below 7, the acidity levels can harm the male sperm, making the odds greater for the female sperm to fertilise instead. It could be a breeding trigger for some species which is why they might do it.
The most likely situation is that the males are eager to breed and do so a few days before the female ovulates, so the male sperm dies off and the longer living female sperm fertilise the eggs when the female does ovulate.
The hormones farms would add, can trigger them to breed early, so it'd be no surprise that males would do their part before the females are ovulating.
I've actually been trying to breed Weeksii, but all 6 I've owned have been female haha, I've not (yet) seen or owned a male Weeksii haha
The females fertilise internally?
Oddball
cloned some in his school days
Oddball
cloned some in his school days
Thats really intresting, what about wild specimen?
Most wild poly in the market are females too, like you mentioned you've owned 6 weeksii and non of them turned out to be male. From what i know all weeksii are WC.
The females fertilise internally?
You're right, they don't haha, females release the eggs and the males cup them with their anal fin and fertilise. Thanks for spotting that, been a long day haha
Don't apply that ovulation comment to Bichirs, incorrect of me to say that.
All I can say on this comment is low pH killing the male sperm, giving higher chances of the female sperm to fertilise, beyond that I can only speculate on this subject
Again, only speculation here, but females live longer and grow larger than males and take much longer to become sexually mature too. Perhaps females have a higher chance of survival in the wild? Suggesting that some populations have genetically weaker males, for whatever reason unknown.
Bit of a wild theory, but perhaps there's more variation in their anal fins than we think and species in some regions have males with smaller anal fins? In comparison to others, they would look female.
