Migration and dispersal of the Rutherglen bug, Nysius vinitor Bergroth (Hemiptera: Lygaeidae), in eastern Australia

Abstract

Aerial sampling for Nysius vinitor Bergroth was undertaken in the surface and upper air, at altitudes of 2 and 100-300 m, respectively, at Trangie in central New South Wales and at Corny Point, Yorke Peninsula, South Australia. Insects were sampled for 15 periods, each of 3-11 days, between October 1979 and February 1984, covering all months except January, March and May. N. vinitor was one of the most abundant insects caught in the upper air during the day and night (mean density of 652/106 m3), while the congeneric N. clevelandensis Evans was rarely caught at any time. N. vinitor was caught in all months sampled except for the winter months of July and August, and the largest daily catches occurred in September. Females were generally less common than males, although the relative incidence in the upper air catches frequently increased significantly from day to night. Fewer mature females were caught in the upper air (0-16·8%) than at the surface (0-48·4%). Densities were generally much greater in the surface air than in the upper air, although during the major flights of spring, there was less than a two-fold difference, indicating increased migratory activity. Migration occurred in a range of synoptic conditions resulting in the displacement of individuals in a variety of directions and distances depending on synoptic flow at the time of flight. Major migrations occurred at night, following dusk take-off, in disturbed weather associated with prefrontal airflows. These resulted in net southward displacements of ca 200-300 km depending on flight duration. It is suggested that major immigration flights into central-western New South Wales and regions to the south regularly occur in early spring (September-October) and probably arise from breeding areas in subtropical latitudes.

Recognition and characterization of migratory movements of Australian plague locusts,Chortoicetes terminifera, with an insect monitoring radar

“…These usually have shapes similar to those of the moths (i.e., predominantly high values of α 2 and low values of α 4 ), but their wing-beat frequencies can extend to 80 Hz. Some are probably smaller moth species (e.g., family Pyralidae and some smaller noctuids), 28 but bugs (Hemiptera) have been reported aloft at night in this general region 33 and a variety of taxa may be represented in the population of targets that are large enough to be detected, at least at lower heights, by the radar.…”

Differential flight activity among karyotypes: daily and weather-induced changes in chromosomal inversion polymorphism in natural populations of Drosophila subobscura

“…For several insect species it has been verified that weather disturbances can cause an increase in activity (Clark, 1969;Iso-Iivari & Koponen, 1977;Dickison et al, 1983;Bergh, 1985;Dickison et al, 1986;Mc Donald & Farrow, 1988). Investigations on this topic are scarce in Drosophila.…”

A native with a taste for the exotic: weeds and pasture provide year‐round habitat for Nysius vinitor (Hemiptera: Orsillidae) across Australia, with implications for area‐wide management

“…Importantly, the ability of juveniles to survive on the ground under their host plants on fallen seeds needs to be considered in such management practices. However, although our findings indicate that there is some contribution of local weeds to the build‐up of pest populations, the low numbers of juveniles relative to adults (assuming comparable sampling efficiency) add support for the premise that adults may originate from hosts further away and migrate into cropping regions (McDonald and Farrow ).…”

“…We show that once pasture crop cover is reduced to less than 20%, N. vinitor densities increase (including juveniles), perhaps because the low cover facilitates the growth of weeds. However, a large unknown remains as to the extent to which N. vinitor is a migratory pest; there is some evidence that it may reside at year‐round breeding sites outside cropping areas, migrating into agricultural regions in spring (McDonald and Farrow ). Whether N. vinitor populations from nearby habitats pose a greater risk than those further afield is an open question.…”