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Am I wrong or are their more Male Zebra’s than Female out there? Everywhere I look people seem to have more males. I have twelve adult Zebra’s, and as far as I can tell only two are female. They were purchased several years ago when they were too small to sex. They were also purchased from several different sources. Are people just hording the females? What do you think?

my guess is that people hoard the females because you can breed multiple females to one male, thus making extra males unessesary

People usually keep either 1 male: 2 female or 1 male : 3 female ratio. So female are less available. With that ratio, male seem to be more abundant. And females always have that potential of spawning, thus hording does occur. my 2 cents

one more reason is that it's easier to catch male WC than female. male will stay to protect its cave while female will ran away so WC zebras are usually male.

Anybody ever toyed with the idea that the tempratures the fish like contribute to a high male ratio?

I may try this theory out when my group starts breeding.

I know that higher temperature produce more females in the reptile world, but not sure about fish. But that is an interesting ?.

I don't think it has anything to do with people hoarding females...although yes people who own zebra's are more likely to sell a male if they have a spare I guess.

Temperature has occured to me before however I see no evidence for this theory. If temperature was a factor then I would imagine that whole spawns would be either female or male. I say this because if a croc lays eggs in a nest then it's the temperature difference (that the egg is subjected to overtime) between the top of the nest and the bottom which detemines whether that particular offspring is a male or female. This variance is impossible to re-create in flowing water over such a small clutch of eggs, especially over any length of time which is what is needed.

I would imagine it has more to do with their breeding process than anything. Males look after the eggs and rear the fry which is a time consuming process, however females lay eggs and that's pretty much it. If a female is able to produce eggs quicker than it takes a male to rear the offspring to the point of independance then, imo, it would be logical to assume that you can have more males than females. Perhaps in nature females lay eggs with one male in one cave and when they are ready, spawn with another male, all the while the first male is still rearing the original spawn. Hence you need more males than females.
You also have to remember that the heirarchical structures probably exist in the river as well. Some males may simply be there to 'help create' the alpha male and so some males my never get to breed because they'll never get to be the alpha in that particular area of river bed, which may also explain why there are naturally more males than females.

Plastic Mac

Plastic Mac wrote:I don't think it has anything to do with people hoarding females...although yes people who own zebra's are more likely to sell a male if they have a spare I guess.

Temperature has occured to me before however I see no evidence for this theory. If temperature was a factor then I would imagine that whole spawns would be either female or male. I say this because if a croc lays eggs in a nest then it's the temperature difference (that the egg is subjected to overtime) between the top of the nest and the bottom which detemines whether that particular offspring is a male or female. This variance is impossible to re-create in flowing water over such a small clutch of eggs, especially over any length of time which is what is needed.

I would imagine it has more to do with their breeding process than anything. Males look after the eggs and rear the fry which is a time consuming process, however females lay eggs and that's pretty much it. If a female is able to produce eggs quicker than it takes a male to rear the offspring to the point of independance then, imo, it would be logical to assume that you can have more males than females. Perhaps in nature females lay eggs with one male in one cave and when they are ready, spawn with another male, all the while the first male is still rearing the original spawn. Hence you need more males than females.
You also have to remember that the heirarchical structures probably exist in the river as well. Some males may simply be there to 'help create' the alpha male and so some males my never get to breed because they'll never get to be the alpha in that particular area of river bed, which may also explain why there are naturally more males than females.

Plastic Mac

Good point.. I didn't even think of that.. very nice and informative

or it could just be that males are superior to females and no little sperm wants to turn into a female so they all decide to be male!

Jojoyojimbi wrote:or it could just be that males are superior to females and no little sperm wants to turn into a female so they all decide to be male!

now if that were the case anyone could persuade the sperm with better treatment of the sex wanted. if you want females then treat the females better than the males and the decision of the sperm is made simple.

The predominance of males of L No's in captivity, and whether this applies to all L No's I don't know, is explained in the Datz book.

Due to the males habit of residing in caves or crevices they are a lot easier to catch. As most L46's where the gender can be determined are still I think Wild Caught IMO the gender inbalance, well this is a good an explanation as any other.

If there is a natuarally occurring inbalance, or other factors influence the sex of offspring, well only time will tell.

Dave

Maybe the temprature question is one I may answer in the near future... My group is not of breeding age yet so this may take a while. LOL