Praying mantids eat only live prey, so in order to feed them you will have to either raise or catch other insects or buy them from a pet store. To get started, it’s easy to catch adult mantids, since they move slowly and are harmless for humans. The males are smaller and easy to tell apart from the larger females. If you manage to catch a female swollen with eggs, you can watch it make an ootheca, or egg case, and lay the eggs.
Caring for females before they lay their eggs
Place a female in a good-size container covered with mosquito netting. Stand a branch up in the container for the insect to rest on. Keep the temperature of the container around 20 to 25°C.
An adult mantid must be fed every three days, with live insects (flies, mosquitoes, crickets, cockroaches, butterflies, moths, etc.) that are no larger than the mantid. Before laying, the female has a large appetite and must be fed frequently. Give it water by spraying the inside wall of the container about once a week or leaving a lid full of water in the bottom of the vivarium.
When it is ready to lay eggs, the mantid will make an ootheca (or more than one) on the branch or the wall of the container. It will die a few weeks after laying eggs for the last time.
If you cannot catch a female, you can gather oothecae clinging to the stems or branches of plants, in the fall and winter. Make sure you put the ootheca in the right direction so that the young can emerge.
Caring for young mantids
Once the larvae appear, give them plenty of food so that they do not eat one another. Offer them small prey to start with, such as aphids, fruit flies and newly hatched crickets. You can isolate them in small containers after they moult for the second time. Empty jam jars or yoghurt containers covered with mosquito netting are perfect at first. Place a branch in each container so that the insect can rest on it when it moults. The height of the branch, from its tip to the bottom of the container, must be at least three times as long as the insect.
Caring for adults
The adults can mate two or three weeks after moulting for the last time. Give them as much as they can eat for several days before putting the partners in the same container. If the female is hungry, she might eat the male before mating. Mating may last for several hours – keep feeding the female throughout this period. Remove the male as soon as the partners separate.
Regularly clean the containers where the young and adults are raised, by removing dead insects and other detritus with tweezers. If necessary, transfer the insects into another container while you are doing the cleaning. Praying mantids must be handled carefully. You can move them while they are on their branch, or coax them into your hand. Make sure not to drop them, even if they lash out and try to bite you.