Chinese Praying Mantis
The most common Ootheca (AKA egg case or ooth) available in the US is the Chinese Mantis, Tenodera sinensis. Originating in China, the Chinese Mantis is the most common mantis in the United States. Ooths are collected in the wild throughout the US by pickers who sell them to wholesalers. The adult females reach 5 inches or so and are quite impressive.
Hatching the Ooth
To hatch the ooth, position is important. The ooth must be hung with the “zipper” down, which is where the 2 flows from the female laying the ooth merge. Glue the side of the ooth the branch is on to the lid and the zipper will be down. The reason for having the zipper down is the nymphs all emerge from this zipper, and hang onto the ooth and each other to dry off. Under the ooth you want some excelsior or grass for the nymphs to climb onto. Some ooths completely hatch out in minutes, some hatch in bursts over days. It takes about 2 weeks to hatch ooths at 80 degrees; lower temperatures will increase your wait time.
Feeding and Hydration
BEFORE the hatch, you will need Bean Beetle Cultures, Rice Beetle Cultures, and Fruit Fly Cultures. The nymphs will eat these tiny feeders for about 2-3 weeks, and they eat a lot. Once they have molted 2-3 times you can feed them small crickets, or our favorite, Blue Bottle Flies. For hydration, you can lightly spray the nymphs, but most hydration needs are met through the food.
If you keep food available, you can house the nymphs together for 2 molts without having too much cannibalism. From the 3rd molt on you will need to separate the Nymphs into 32-ounce insect cups. The 32 ounce insect cups give enough height for the mantis to molt; if during a molt they touch the bottom, the molt will not be successful, resulting in deformities, and/or death. They can stay in the 32-ounce cup until they are 2 inches long.
Ooths are collected November through February in the US, and then held at wholesalers under refrigeration until the next years’ pick. By August, the hatch rates begin to drop on the refrigerated ooths. The size of the ooth is proportionate to the hatch rate, so getting large ooths is better. Mantids will eat honey off of a popsicle stick in your hand, a great show for kids.