Evidence for Obligate Migratory Flight Behavior in Young European Corn Borer (Lepidoptera: Crambidae) Females

Abstract

European corn borer, Ostrinia nubilalis, flight behavior was examined in laboratory experiments. Adults were each tethered to 1 of 16 round-about flight mills in an environmental chamber, and the data were relayed to a computer. Parameters analyzed included duration, distance, and speed of the longest continuous flight and total flight time during an 8-h night. Comparisons were made between unmated and mated adults of both sexes at different ages up to 5 d after emergence. For unmated females, duration of the longest flight was highest the first night after emergence, declining significantly by 5 d of age. In contrast, duration of the longest flight for males was lowest at 1 d of age, increasing significantly by 3 d of age. Flight speed of females was roughly twice that of males at all ages. Mating did not affect flight behavior of either sex at any age tested, but mated adults could not be tested before 2 d of age because the first night was needed for mating. The pattern of age-specific flight behavior suggests that unmated females engage in obligate migratory flight the first full night after emergence. The median duration of this flight was ≈2 h in our experiments, with some adults flying continuously for the full 8 h of darkness. Females of other ages and males of all ages tested were capable of long-duration flights, but they more likely represent foraging flight. These results help explain the high dispersal rate of newly emerged adults from release sites in field experiments. KeywordsOstrinia nubilalis, migration, dispersal, flight behavior, flight mill ABSTRACT European corn borer, Ostrinia nubilalis, ßight behavior was examined in laboratory experiments. Adults were each tethered to 1 of 16 round-about ßight mills in an environmental chamber, and the data were relayed to a computer. Parameters analyzed included duration, distance, and speed of the longest continuous ßight and total ßight time during an 8-h night. Comparisons were made between unmated and mated adults of both sexes at different ages up to 5 d after emergence. For unmated females, duration of the longest ßight was highest the Þrst night after emergence, declining signiÞcantly by 5 d of age. In contrast, duration of the longest ßight for males was lowest at 1 d of age, increasing signiÞcantly by 3 d of age. Flight speed of females was roughly twice that of males at all ages. Mating did not affect ßight behavior of either sex at any age tested, but mated adults could not be tested before 2 d of age because the Þrst night was needed for mating. The pattern of age-speciÞc ßight behavior suggests that unmated females engage in obligate migratory ßight the Þrst full night after emergence. The median duration of this ßight was Ϸ2 h in our experiments, with some adults ßying continuously for the full 8 h of darkness. Females of other ages and males of all ages tested were capable of long-duration ßights, but they more likely represent foraging ßight. These results help explain the high dispersal rate of newly emerged adults from release...

Effects of Larval Density on Flight Potential of the BeetWebworm,Loxostege sticticalis(Lepidoptera: Pyralidae)

“…Adults are typical migrants with great ßight potential and a relatively long prereproductive period Li 1993b, Cao et al 2006). Adult migration usually occurred before ovarian maturation (Feng et al 2004), which was also observed in other pyralid species such as Cactoblastis cactorum and Ostrinia nubilalis (Dorhout et al 2008, Sarvary et al 2008a. Adults can ßy continuously for 24 h and have ßown a maximum distance Ͼ100 km in a 24-h tethered-ßight test (Luo and Li 1992).…”

Role of dispersal in resistance evolution and spread

“…But the argument of improved mixing of adults in a blended refuge field does not apply to species where significant dispersal from the natal plant occurs before mating. For example, young European corn borer, Ostrinia nubilalis, females disperse long distances before mating [59], a behavior common among many Lepidoptera, especially migratory species.…”

Spatial and Temporal Genetic Analyses Show High Gene Flow Among European Corn Borer (Lepidoptera: Crambidae) Populations Across the Central U.S. Corn Belt

“…An exception is a study by Showers et al (2001), where marked adults were recaptured 23Ð 49 km from the release site, but no traps were monitored beyond 49 km. Flight mill studies by Dorhout et al (2008) indicated that 1-d-old unmated females engage in obligate migratory behavior, with maximum distances of Ͼ20 km observed for both males and females. Range and ecotype expansion data (Chiang 1972, Showers 1979, Showers et al 1995 and circumstantial sampling data (Caffrey and Worthley 1927, Colenutt 1995, Bretherton and ChalmersHunt 1989, Langmaid and Young 2006 suggested that European corn borer dispersal can occur up to at least 80 km, but the frequency of dispersal to these distances or beyond has not been determined.…”