Crickets are omnivores and scavengers by nature. They can feed on almost anything, including fresh plant material, decaying organic matter and, when they are extremely hungry, both living and dead insects. Some cricket species can become entirely carnivorous and serve as predators to weakened or crippled insects. Crickets tend to be nocturnal and hunt for their food at night.
Field crickets prefer to eat fresh plant material, such as vegetables, fruits and seedling plants. They can significantly damage and wipe out agricultural crops and may also feed on newly planted seeds. Some crickets help keep annoying weeds at bay by feeding on the plants, but other species, such the mole cricket, dig holes underground and prevent agricultural seeds from germinating. Field crickets are known for eating grasshopper eggs and the pupae of butterflies, moths and flies.
A scarcity of food in their natural habitat can cause some cricket species to develop carnivorous tendencies. The armored cricket found in the African continent can become cannibalistic if they lack protein and salt. The rare, tusked weta is mainly carnivorous by nature. Their diet includes earthworms and insects. Weta crickets are indigenous to New Zealand and have existed since the age of the dinosaurs.