In the laboratory, they eat apples, lettuce and dog food. They are well known for their comical, yet effective, defense tactics. When alarmed they stand on their heads by bending their front legs down and extending their rear legs. Depending upon the species, they exude an oily, musty secretion, which collects at the tip of the abdomen or spreads over posterior parts of the body, or they eject the reddish brown to brown secretion as a spray. Larger desert species, like E. armata and E. longicollis, can spray 10 to 20 inches.
Most species can spray multiple times, if necessary.
The spray is not painful unless you get it in your eyes or mouth, where it is painful, burning and temporarily blinding. It does not wash off. The larvae of certain Eleodes species are also known as false wireworms, and they are a pest of some commercial crops in the Midwest. Larvae are slender, shiny, darkish green to brown, and hard bodied. They feed on the seeds and seedlings of wheat, sorghum, all oilseeds, grain legumes and cereals, particularly in light, draining soils with a high organic content.