Activity of Tobacco Hornworm and Corn Earworm Moths as Determined by Traps Equipped with Blacklight Lamps123

The influence of moonlight on catches of insects in light-traps in Africa. III. The effective radius of a mercury-vapour light-trap and the analysis of catches using effective radius

“…Mitchell et al (1972), using electrocutor grid traps baited with a blacldight lamp, virgin females or both, showed that in Florida peak catches of males of Manduca sexta (Joh.) occurred well after midnight Stewart et al (1967), in North Carolina, found most M. sexta in blacklight traps very much earlier, two or three hours before midnight However, as Mitchell et al observe, their records from Florida refer to a two-week period in late July, whereas Stewart et al present totals for two seasons extending to September and October, respectively. It is possible that declining temperatures in early autumn induced an earlier flight period which may have weighted the whole-season catch towards the early part of the night, but with appropriate ambient temperatures Sphingki activity is much later in the night This is a surprising conclusion in view of the frequency with which often large numbers of Sphingidae are seen visiting flowers at dusk.…”

An Analysis of Factors Affecting Catches of Insects in Light-Traps

“…Glick (1939) found that the density of Lepidoptera fell by two-thirds between heights of 150 and 300 m; at 650 m, the density was less than one-tenth that at 150 m. The estimated heights of radiation equality for conditions comparable to those at Muguga are of the right order of magnitude, and differences between traps are large enough to allow variations in density gradients to influence trap catches. By caging moths in a black container pointed towards a 15-W ultraviolet source, Stewart et al (1967) found response limits of 60 to 90 m for H. zea and 120 to 1356 m for Manduca sexta. Using a similar technique, Plaut (1971) showed responses by S. littoralis beyond 200 m but not beyond 250 m. Agee (1972), using electrophysiological techniques, found that in H. zea the least sensitive and most sensitive moths could detect radiation from a 15-W ultraviolet source at 31 and 250 m, respectively.…”

“…Empirical determinations of response distance have been made by exposing insects to light sources at different distances (e.g. Stewart et al, 1967;Plaut, 1971) or by electrophysiological techniques (e.g. Agee, 1972).…”

“…There have been some estimates of distances at which insects appear to respond to radiation from light sources, e.g. Stewart et al (1967), Plaut (1971) and Agee (1972). These workers all used a 15-W mercury vapour source and found response distances to vary between about 50 and 250 m. There have also been attempts to describe and quantify the region of influence of a light-trap.…”

Migration and behavioral studies of two adult noctuid (Lepidoptera: Noctuidae) species plus feeding observations of some moths common to Iowa

“…Most notable was a study in India, showing a peak occurred during the last 4 hr of night early in the cotton (Gossypium hirsutum L.) season, the middle 4 hr in mid-season, and the first 4 hr at the end of the season (Hussain et al 1934). The maximum activity of tobacco hornworm moths, Manduca sexta (Johannson), was 2100 to 2200 hr for males with a steady decline after 2200 hr (Stewart et al 1967). Females were similar to males except activity was reduced between 2000 and 2100 hr.…”