We have a lot of praying mantis here. I've never seen one eat a garden worm but they will enjoy a meal-worm. The praying mantis' diet consists of aphids, mosquitoes, caterpillars, beetles, flies, leafhoppers, mites, grasshoppers, crickets, moths and any other tiny insects who happen to haplessly wander by. Large mantis will occasionally eat humming birds and tree frogs. Their digestive systems are able to handle small lizards, tiny rodents and baby snakes. They also feed on one another, which is why they tend to live in solitary.