I free range my chameleons so I really have to pay close attention to when it’s time to lay eggs. I think one of the most important things is to have a gram scale and weigh her once a week. If she's gaining and you are still feeding the same amount of food then I figure she must have eggs. You can buy a gram scale cheap on eBay http://www.ebay.com/itm/Digital-Die...all_Kitchen_Appliances_US&hash=item337bcfa473 or you can buy one at Wal Mart with the small kitchen appliances. They have a bowl on top and they are really for weighing food but they work great for chams. I put a wash cloth over the bowl to give them something to grip on to, zero out the scale and then put the cham on. You can weigh from the smallest baby right up to largest Melleri. Camille, my female veiled never seems to show, what people call gravid colors, so by keeping a written record of her weight every week it helps me to know when she’s got a clutch.
Camille was 14 months old before she laid her first clutch but I always kept her cooler, 80 to 83 for basking and I cut way back on her food at 5 and ½ months old. Over Camille’s free range I have the double fluorescent hood that houses a tube/linear Repti-sun 5.0 and a regular white fluorescent tube light. In my house this keeps the temperature in the low 80's. I found out about the lower temps and smaller feedings in Lynda Horgan’s blog http://raisingkittytheveiledchameleon.blogspot.com/2007/12/keeping-female-veiled.html Cutting back on the food helps to stop her from forming a clutch or at least if she has a clutch is should be a small one. A lower temperature helps to slow the metabolism to hopefully make these little starving girls not quite so hungry. A temperature gun is also very important so that you can point the laser right on their body to make sure they are not getting too hot. You can also get a temp. gun on eBay for a really good price. http://cgi.ebay.com/CRAFTSMAN-NON-C...=270727271403&ps=63&clkid=8764176996846397009
Sometimes keeping them cooler and cutting back on their food will not prevent them from laying eggs. That’s why is so important to keep up with their weight. Since I free ranges the way I can tell when it's time to put Camille in her laying bin trash can, is when she won’t stay in her trees and she's roaming around all over the place looking for a place to lay those eggs. Sometimes she will stop eating a few days before she lays but not every time.
I have to use a large trash can (the kind you wheel out to the side of the road for the trash man). The first time Camille laid eggs she laid them in her plant and she has two regular laying bins available to her. After that was when I started using the trash can. You can see pictures of the trash can in this link: http://www.chameleonforums.com/camilles-eggs-43-them-they-fertile-28568/
Lynda (kinyonga) recommends putting a smaller container (12" x 12"deep x 8"wide) of washed playsand in the cage for the female to dig in so that you don't miss the often subtle indications that she is ready to lay eggs. Once she starts digging in this container, then you can move her to the larger one. Some females will lay in a container this size so if she's busy digging just leave her alone and she may very well lay her eggs there.
For a regular laying bin I would not use anything smaller than a 12X12X12 and a 14X14X14 or a 16X16X16 would be even better.
You need to have 12 inches of substrate in the bottom of the can. I use washed play sand. It’s very important to have the sand moist so that it will hold a tunnel and not cave in on your female. I take a big spoon and dig a tunnel all the way to the bottom to make sure it’s going to hold the tunnel. If it’s too dry or too moist they will refuse to use it. Some females will dig several test holes before they finally get one they like. I usually leave my test hole and sometimes Camille will use it.
Once you have determined it’s time for them to lay eggs you must give them complete privacy. If they see you looking they can abandon the hole and become egg bound. It will take hours for them to dig the hole and get it just the way they want it. Camille once spent all night in the laying bin. She did stop digging and went to sleep in the hole and early the next morning she was digging again. I was afraid to move her and just left her in the hole over night. The tunnel is usually slanted toward the side of the can and goes all the way to the bottom. I would not put more than 12 inches of sand in the bottom because they will dig to the bottom and it’s too hard on them to have to do so much digging.
While digging the hole they will be head first in the hole. Once they get the hole to their liking they will turn around and lay the eggs. Usually this doesn’t take nearly as long as digging the hole. Again, very important, DO NOT let your female see you looking. She needs complete privacy to lay these eggs. Once she’s finished laying the eggs she will start covering up the hole and then pat the sand down and return to the branch. Camille is always exhausted and once I see her covering the hole I get her out of the laying bin and return her to her tree. She is very weak and needs plenty of water and food. First I give her a really long misting to get all the sand off her and she takes several long drinks. Then I give her several feeders (silkworms are excellent at this time) heavily dusted in calcium with no D3. I would highly recommend buying some liquid calcium and keep it on hand for your female. Once I notice that Camille has eggs I give her a drop of liquid calcium once a week until she lays the eggs. After she lays the eggs I give her a drop or two every day for 3 to 4 days. If you don’t have liquid calcium, then heavily dust her feeders with plain calcium for 3 to 4 days after she’s laid eggs. I feed her very well the first fews days after laying and then after 3 or 4 days I put Camille back on her regular feeding and supplement schedule.
When your female comes out of the laying bin she should look very thin. If she’s still fat then you have a problem because she has not laid the eggs. I always weigh Camille after she's out of the laying bin and she's always 20 to 22 grams lighter. If your female didn't lay the eggs you can try leaving her in the laying bin for longer but I would take her to a good chameleon vet at the first sign of a problem. Many of the females die from egg problems and live a shorter life than the males. If you get her to the vet in time a vet can give oxytocin to induce egg laying before she becomes egg bound. Several injections of oxytocin over several days might be needed. If she still doesn’t lay the eggs surgery is the only other alternative. Surgery is very risky but at this point it’s the only choice. If your female is healthy and your husbandry is right she shouldn't become egg-bound unless she has a reproductive system deformity, deformed eggs, etc.
I incubate the eggs the same way that Lynda (kinyonga) does. Put them in a plastic Tupperware shoe box with about 3 inches of moist vermiculite and keep them in a closet where the temps with be around 76 degrees. I punch two tiny holes in the lid. To test for moisture, take a fist full of the vermiculite and squeeze it, if no more than a drop or two of water comes out then the moisture level should be okay. Do not turn the eggs as you move them from where they were laid to the container. Lay them in rows about an inch apart in all directions in shallow dents made with your thumb in the vermiculite. Put the lid on and place them in a dark place where the temperature is between 72-78 F. Moisture will form on the sides of the container and underside of the lid. It takes about 8 to 9 months for the eggs to hatch. It they are not fertile they will mold over in a couple of weeks.