Mantids are insectavours. They eat insects primarily pollinators such as flies, moths, bees etc.. Using commercially raised feeders (flies) from USDA approved farms or clean home made cultures assure good nutrition and clean uncontaminated food.
There are many other feeders people use. Crickets, roaches, and worms of different types.
Captive mantids health depends on your understanding of nutritional needs and what is safe food . Using commercially raised feeders from USDA approved farms assure clean uncontaminated food.
It is not recommended to use wild caught food as they are contaminated with pesticides and feed on some pollin that can be naturally toxic. Most communities spray for mosquitoes. The chemical used is poisonous and dangerous for Mantis. Wild Pollinators feed on natural toxic plants such as Foxglove (Digitalis extremely poisonous). There are regions where it’s poisonous affects makes even local honey dangerous to eat for humans.
Crickets, worms, and roaches. Many people use these and I’ll give you some facts. Crickets, mealworms and roaches have a thick exoskeleton made of ‘critin”. Mantids do not digest this easily as it has a strong gluey paste-like composition. Insects with thick exoskeletons also shed them and will hold bacteria even if raised in a clean environment. Food and feces particles trapped between the plates or sheds will fester and can even contain botulism. Some feeders such as crickets and mealworms are raised for the reptile trade and gutloaded or given feed that is unhealthy for Mantids. Crickets bite! As well as some other feeders. Even a tiny bite will kill a Mantis
The standard for success are USDA farm raised organic flies or cultures made from them at home.
Note: there are many successful breeders and keepers who use other insects as feeders and know which Mantis species tolerate roaches etc better than others. They also have a standard of cleanliness for thier feeder. “The standard with using flies as suggested will minimize health issues” I am frequently contacted with people who’s Mantis is suddenly sick and dying often fed other than flies just prior.
How much and how often should Mantis be fed? Naturally mantids evolved for feast and famine. Hatching flies in nature happen in mass to ensure thier reproduction. Mantids and other animals will gorge on them. Adversely, drought, heat waves and cold periods cause food scarcity for weeks even months.
This said you can feed often and a lot. It becomes too much when the feeders cause stress or a dirty habitat for your Mantis. Especially with nymphs, they run around in panic like ways caused by too many feeders or crowding. A Mantis can survive for as many as 6 weeks without food. This of course would be cruel if you left them without for such a long period, but important to know. Don’t panic if your feeding schedule may be upset while your feeding cultures regenerate and hatch or while your delivery make take a week or so.
Note: Water should be always available. Misting several times daily in a well ventilated habitat is necessary.
Can my Mantis eat a frog, bird, mouse? No! If your curious that’s natural, however there is no reason too. Firstly your Mantis will get injured and die. It is also a cruel act and I feel strongly about those who focus on the “kill”. Enjoying watching your Mantis hunt eat and be healthy is nice, but there is absolutely no room for sadistic satisfaction or obsession with the killing. If this is what you like but a poisonous snake and sleep with it!
Supplements, honey and junk food. Honey is sugar and of no nutritional value especially to Mantids. Some misconception about it confuses people. I read “Give it to your Mantis when sick or injured” and “It’s a natural antibacterial” or “My Mantis loves it”. Pay attention here, Mantids will eat Pooh if you put some on you finger and offer it! Don’t be confused, Mantids are Insectivors and eat pollinators. They may in the wild eat things like pollen or other things likely for the moisture. Likely honey will gum up a Mantis digestive tract, can contain toxins especially natural unprocessed, and even dry like “Fly paper glue” later wondering why it’s sick or dead.