Reptile & Amphibian Forums

I dont think they are all good though, some are pretty soft right now just put them in the incubator, but I'm sure some are no good.

I was surprised to see her lay 5 this second round, as I always have heard they (Vestigium only lay 3- 4) so that was something new.
And they were all very good size for the 2nd clutch to.

One I do see the pink ring and is hardening quickly, so I know theres one anyway .

I'm finding with the Vestigium in particular, it's tough, as far as eggs. She layed 3 in April , told you guys one I'm waiting for very patiently its 51 days today !

But the other 2 stopped growing , and got funky, I opened one before dumping, to find a tiny vestigium in there, but it had surely been dead.

Kind of Sad, that some make it and others do not. Some lizards have them all hatch. Well, see what happens !

I know I will be pretty dang dissapointed if this one egg thats ready , for some reason does not make it now! AHHhh, talk about bummed.
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Eve

Congrats on the second clutch.

Eve... In the past I have witnessed female C. vestigium lay up to six eggs in a single clutch; however, average clutch size (in captivity) would seem to be about four. Duration of incubation for eggs of this species is generally 60-72 days, or slightly longer on average than for C. collaris. These observations are based solely on my first-hand experiences with collared lizards in captive environments. As DC would probably suggest, your mileage may vary... Yes, the presence of a pink oval on the egg(s) from Chia's most recent clutch is definitely a good sign. Best of luck with those, and the lone remaining egg from her first clutch!!

Brock

to know, as far as taking longer.

I did not know that, being the first Vestigium egg I ever incubated. I have learned it takes her longer to lay than C. Collaris.

They are also alot bigger the eggs, almost Bearded dragon size.

I have seen it grow the whole time, to big, very plump and firm. But this last week it seems to have stopped at this size.

Thats why I thought it to be almost time. But its only 51 days.
So I guess I still have a ways.

Since I last posted Her eggs she layed today, 4 look to be bad, very squishy. One is pink and firming.

I don't understand why so many are not good each time.
Only one from the 1st clutch,(the one I'm waiting on) the other 2 did not make it long. But they had dead little lizards inside.

Have any idea why Brock? Do they normally have infertile and fertile eggs?

Eve
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Eve

regarding why some eggs from a given clutch are "good" and others are "bad"...it seems clear that not all of the eggs are being fertilized, for whatever reason. Perhaps the male is not producing enough viable sperm during copulation? Occasionally one of my C. dickersonae clutches contains at least one egg that is obviously infertile. I try to minimize this occurrence by introducing receptive females to more then one male during the time of ovulation. Of course, many folks don't have additional male Crotaphytus of same species to use for this purpose...

Brock

I would suspect a problem other than infertility; especially if the "bad" eggs have had a partially developed embryo. I would focus on factors such as incubation parameters (type of incubator: fan-forced, etc; incubation medium; temperature fluctuations; relative humidity, etc.) or the overall health of the adult animals. At least in my experience working with Old World chameleons, slight temperature fluctuations and complete darkness during incubation are essential to the development and eventual survival of the embryos. The physiological differences among the two families (Chamaeleonidae and Crotaphytidae) are obviously present, and it is possible that fluctuations in temperature may present a danger to the development of Crotaphytus eggs. Has anyone had a chance to experiment with a variety of constant temperatures? Are fluctuations better than a constant?

Regards,

Fabian Aguirre
Zookeeper/ Freshwater Aquarist
Department of Herpetology and Freshwater Biology
The Dallas World Aquarium
(214) 720-2224
www.dwazoo.com

as to my definition of a "bad" egg. I was referring in this case only to those eggs which, based on visual observation immediately following oviposition, are clearly not destined to hatch (e.g. mushy, off-color). I suspect that the vast majority of these are infertile eggs...
As for those eggs which contain partially developed embryos but never hatch, fertility is obviously not the issue. It is interesting that some eggs from a given clutch will hatch successfully, while others from the same clutch - and incubated under identical conditions - do not. I agree that the health/nutrition of the individual females could often be a determining factor in such cases (assuming incubation prerequisites are met). Perhaps resulting in weaker structure in selected eggs on occasion? Just a thought...

Brock

Just frustrating !
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Eve

Have you guys messed around with the moisture content of the incubation substrate? It seems to me that the dickersonae, vestigium and nebrius may come from a lot drier habitat than collaris. I know chuck eggs will spoil into the incubation period in the same way if they are kept too wet. Just a thought.
Tom

Appreciate the imput. Can always use more ideas and everyones slate on things.
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Eve

Got too much slate on my mind, hehhehe use it in all the tanks.
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Eve

Eve,

You could technically "speed-up" the development of the eggs by increasing the temperature at which they are kept. This is NOT recommended as problems could emerge. For example, the recommended incubation temperature for Crocodyluys intermedius is around 31.5 celcius. Last year we incubated these at a higher temperature, thus causing the crocodiles to hatch more quickly (and prematurely), and preventing them from absorbing their yolks correctly.

So if your temperatures have been higher than the "recommended" average, you might be in for a surprise... unfortunately.

Regards,

Fabian Aguirre
The Dallas World Aquarium

Thanks, but it is not that, temps are pretty normal 83 degrees.
Out of the 5 eggs layed today It seems one is fertile, so far, the others are squishy, and appear infertile.

Ahhh, I dont know, maybe Brock is on to something as far as allowing more than one male mate with them.

Have to see what happens, nutrition and health do not seem to be a problem.

Thanks so much for your input, always welcome,

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Eve

Good luck with the eggs. I agree that vestigium are the most difficult to get hatchlings from.