While the foul flavor of ladybugs teaches most mammals and birds to avoid eating them, it does not affect toads, and they are frequent predators of these small, helpful insects. Toads use their long, sticky tongues to catch ladybugs, just as they do other flying insects.
Certain species of assassin bugs also eat ladybugs. These insects have a long beak with which they inject a toxin to dissolve tissue of their prey. In addition to ladybugs, their diet includes caterpillars, flies and mosquitoes.
Spiders also eat ladybugs trapped in their webs. In times when food is plentiful, the spider paralyzes the ladybug and spins it inside a protective web to store for leaner days.
Due to their natural defense system, ladybugs are better known for the prey they eat and not for being prey. Gardeners prize ladybugs for their role in eating aphids, a common pest for roses and other flowers, as well as for fruit trees and vegetable gardens. A single ladybug consumes thousands of aphids in its lifetime.
When aphid populations are low and ladybug populations are high, ladybugs eat other ladybugs, according to About.com. Most of the time this cannibalistic practice occurs after an adult ladybug molts her hard shell. However, hungry ladybugs also eat ladybug eggs and pupae when in search of protein.