Some species also climb into trees, shrubs, and crop plants looking for prey. Adult ground beetles run quickly when disturbed, but they rarely fly. Some species emit a strong smelling irritant when handled. Many are nocturnal and some are attracted to lights at night. In general, arable land contains more carabids than does land planted to permanent crops such as clover or alfalfa.
Most species are more common on clay than on sandy soils.
The adults are fierce predators that chew up their prey with their large, sharp mouthparts. Caterpillars , grubs and adults of other beetles, fly maggots and pupae, earthworms, and other small soil dwellers are common prey for many ground beetles. They can consume their body weight in food daily. Eggs are deposited either on objects above ground or in cavities made in the soil. One of the better studied ground beetles in vegetable crops, Lebia grandis , lays hundreds of eggs.