Classical biological control of Scapteriscus spp (Orthoptera: Gryllotalpidae) in Florida

The effects of classical biological control on pest mole crickets, Scapteriscus spp., in Florida were examined. Incidence of infection of sound-trapped Scapteriscus spp. by the entomopathogenic nematode Steinernema scapterisci Nguyen & Smart ranged from 0 to 45.3% for collections made near Gainesville and. Bradenton during 1991, 1992, and 1994. Twelve of 49 mole cricket collections from 15 counties made from November 199'' to April 1995 contained individuals parasitized by the tachinid Ormia depleta (Wiedemann). Parasitism levels from 0 to 25.0% and from 0 to 24.1% were observed for female and male Scapteriscus vicinus Scudder, respectively. Mean total yearly sound tray, catch of S. vicinus was reduced 36 and 25% at 2 sites near Gainesville after establishment of the 2 natural enemies; catches of Scapteriscus borellii Giglio-Tos were reduced 70 and 64%. At Bradenton, catches of S. vicinus and S. borellii were reduced 81 and 5%, respectively, since the beneficial species were established. However, catches of S. borellii have declined by 81% in the last 3 yr. Results indicate that classical biological control of pest mole crickets in Florida is succeeding.