TortoiseForum.org

Hi everybody. I am new here, and have a question that I hope maybe somebody can answer.
I have 2 Desert Torts, an adult male and an adult female. Both appear very healthy.
To be blunt, they have sex all the time, almost daily (I should be so lucky). But after 5 years, I have yet to get any eggs. I am wondering what the problem is.
Is there an age at which they are no longer fertile? The female is about 50 years old I was told by the previous owner. I don't know how old the male is, but he's probably up there too.
Also I am wondering if it may have something to do with their relative size. The male isn't very big, about 9.5 pounds. The female is a bit larger, about 13 pounds. Yet when they do "it" it appears the act is successfully consummated (what a mess!)
Any light anybody can shed would be greatly appreciated!

Hi Shelly and welcome to the Forum. Can you tell us or post a pic of their habitat? Where are you located?

Hi Shelly: Are you sure that the male is a Gopherus agassizii? From the size I might hazard a guess that he is a Texas tortoise. Can you put up a picture of his plastron for us to see? As for fertility and age, it has been discovered that females at the very end of their lives...upwards of 80 years and more...have the ability to lay viable eggs. I don't recall if the study included the viability of a male's sperm at an older age, but at only 9 and a half pounds, I would say he's not that old (or he's not a Calif. desert tortoise.)

Another thing to think of is red ants. If I allow any of my different kinds of tortoises' eggs to stay in the ground the ants eat through the shell and eat the eggs.

A note of caution: According to the Department of Fish and Game, it is illegal to artificially incubate desert tortoise eggs. If you should happen to have a nest of eggs, you are supposed to let nature take its course.

Yvonne

I live in the Los Angeles area, in the San Fernando Valley. The torts live freely in my large backyard. They are pretty self-sufficient, and seem to need almost no care on my part. There is a large variety of edible plants on my property, and have a good diet and shelter.
Here are some pics. The top is my female "Bubbles". Next is the male "Rover" You can see a healed crack in his shell from a car accident many years ago.
Bottom shows them together, along with my 9 year old, "Philbert". I got him when he was a week old!
The male does have a slightly different appearance than the other 2. His shell is smoother and grayer than the others, and his skin is not nearly as "spikey" as the others. Maybe he is a different variety? I was told that they both were "California Desert Tortoises" when I adopted them
I am sure the male is fully grown, as I have had him for over 11 years, and he hasn't grown too much if at all in that time. I have had the female for about 7 years.

I'm pretty sure that the male with the cracked shell is a Gopherus berlandieri, or Texas tortoise. They have a more wedge-shaped head, and I see that in his head. Also, they have a VERY DEEP indentation on their plastron, that's why I asked for a plastron picture. But even without seeing the plastron, I'm pretty sure he's a Texas tortoise. I'm given Texas tortoises frequently by people who believe they are California tortoises. Aside from their smaller size, they are pretty hard for your average non-tortoise person to i.d.

Yvonne

Wow, thanks for the info. I had no idea. Yes, he does have the deep indent you describe.
Is that why there have been no offspring? Different species?

Here's an excerpt from an article written by Michael Connor (Molecular Biology and the Turtle:
The desert tortoise and its relatives):

"When the scientists compared DNA from all four species of gopher tortoise they confirmed the close link between X. agassizii and X. berlandieri, and between G. flavomarginatus and G. polyphemus. Their results suggested that the Xerobates and Gopherus forms last shared a common female ancestor some 5-6 million years ago. The Texas tortoise, X. berlandieri, proved to be very closely related to the "eastern" agassizii genotype. It is highly likely that berlandieri evolved from this eastern agassizii assemblage, probably from Xerobates stock inhabiting the north central region of Sonora. Perhaps the closeness of the relationship between the eastern agassizii assemblage and berlandieri explains the occasional occurrence of hybrids from matings between captive Texas and desert tortoises."

So it looks like they do interbreed in captivity and that they are closely related.

You mentioned something in your first post that might be the answer. You said that they were actually consumating the act because it was "messy". I think that would more than likely mean that actual breeding was NOT taking place. There usually isn't any "mess" involved, as the male tortoise's penis is inside the female when the sperm is let go. So maybe there really isn't actual copulation going on, he's just going through the motions???

Yvonne

Thanks again Yvonne.
I never knew a tortoise had a penis. I don't think there is any penetration. Probably due to the difference is size, I guess.

For those of you who are faint-of-heart, please don't look at this picture. For others, this is what the tortoise penis looks like in full regalia:



That is how it gets "stuck" inside the female, until the sperm is released.

Yvonne

ew - but thanks for sharing - now I really hope Percy isn't a male!