These beetles often congregate in both flowing and still water, especially streams and ponds. Adults feed on organisms on the surface of the water or scavenge debris. They spend much of their life on the surface of water. Some Dineutus species can secrete a milky substance which emits an odor that resembles ripe apples while Gyrinus species emit an unpleasant odor. They can swim rapidly.
Adults feed on organisms on the water surface or by scavenging debris.
Larvae are predators on aquatic organisms. Larvae are seldom seen but are found in the bottom of streams and ponds. Adults are sometimes attracted to lights. None, this is a beneficial insect. For additional information, contact your local Texas extension service agent, or search for other state extension service offices.