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Light Trap Catches (light + trap_catch)
Selected AbstractsHigh-altitude migration of the diamondback moth Plutella xylostella to the U.K.: a study using radar, aerial netting, and ground trappingECOLOGICAL ENTOMOLOGY, Issue 6 2002Jason W. Chapman Abstract 1. The high-altitude wind-borne migration of the diamondback moth Plutella xylostella in the U.K. in 2000 was investigated (a) by direct monitoring of insect flight by vertical-looking radar and by aerial netting, and (b) through evidence of temporal variation in P. xylostella abundance deduced from a network of light traps. 2. Migrating P. xylostella were identified by a unique combination of size and shape data derived from the continuously operating vertical-looking radar. 3. Radar-detected migratory overflights correlated significantly with associated peaks in abundance of P. xylostella estimated by catches in a U.K.-wide light trap network; however the correlation was stronger when light trap catches were lagged by 1 day. 4. The first notable catches of P. xylostella in the U.K. occurred in early May, and were accompanied by migrations over the radar from the east. 5. Radar data and back-tracking indicated that a major wind-borne migration of P. xylostella from The Netherlands to southern England took place in early May, and that this was responsible for the establishment of the U.K. population. 6. The origin of early-season P. xylostella occurring in Britain is discussed. [source] Larval habitats and seasonal abundance of Culicoides biting midges found in association with sheep in northern Sardinia, ItalyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2010C. FOXI Between January 2005 and December 2006, the larval habitats and seasonal abundances of 21 species of Culicoides (Diptera: Ceratopogonidae) found in association with livestock on a farm in northern Sardinia were studied. Culicoides were collected using two light traps (one placed in a sheep shed and the other near water ponds) and reared from mud collected in and along the margins of a small and a large water pond. The mammalophilic Culicoides imicola Kieffer and Culicoides newsteadi Austen were the most prevalent (>95%) of 20 species in the sheep shed, whereas the ornithophilic Culicoides univittatus Vimmer, Culicoides sahariensis Kieffer, Culicoides festivipennis Kieffer, Culicoides circumscriptus Kieffer and Culicoides cataneii Clastrier were most abundant in the traps set at the ponds (73%) and in 16 species of Culicoides reared from laboratory-maintained mud samples retrieved from three microhabitats (a non-vegetated pond shoreline, 20 cm above a pond shoreline, the shoreline of a secondary, permanently inundated, grass-covered pool). The species reared most abundantly from along the pond shoreline were C. festivipennis, C. circumscriptus and C. sahariensis, whereas those most prevalent at the grassed pool were C. cataneii and C. festivipennis. C. imicola was found to breed preferentially in mud 20 cm above the pond shoreline, whereas C. newsteadi was restricted almost entirely to the grassed pool, which had a high organic matter content. Using the light trap and adult emergence data, the seasonal abundance patterns of the eight species of Culicoides were determined. In general, there was good correspondence between light trap catches and emergence trends. Well-defined emergence peaks indicate four or five generations for C. festivipennis and C. circumscriptus and three generations for C. cataneii, C. newsteadi and Culicoides jumineri Callot & Kremer. The emergence trends for C. imicola and C. sahariensis were unimodal, but, because they stretched over several months, indicated that a number of overlapping generations had occurred. Adults of C. imicola were reared and captured only sporadically in the first half of the year, gradually building to a peak in autumn. Conversely, C. newsteadi was reared throughout the year and displayed three clearly defined peaks (in winter, spring and autumn); captures of C. newsteadi in the light traps peaked in May,June and again to a lesser extent in autumn. In Sardinia the late seasonal peak in the abundance of C. imicola occurs in synchrony with outbreaks of bluetongue (BT) in sheep, which is consistent with earlier findings elsewhere in the Mediterranean basin and in Africa that it is the principal vector of bluetongue virus (BTV). Although the status of C. newsteadi as a vector of BTV is not known, its low-level presence in winter and heightened abundances in spring may provide a pathway along which the virus can overwinter. [source] Spatial distribution of bluetongue virus and its Culicoides vectors in SicilyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2004A. Torina Abstract., During the recent Mediterranean epizootic of bluetongue, an extensive programme of serological and vector (Culicoides biting midges (Diptera: Ceratopogonidae)) surveillance was carried out across Sicily. This paper presents the analysis of 911 light trap catches collected at the times of peak Culicoides abundance (summer to autumn 2000,2002) in 269 sites, in order to produce detailed maps of the spatial distribution of the main European vector, Culicoides imicola Kieffer and that of potential novel vectors. Whereas C. imicola was found at only 12% of sites, potential novel vectors, Culicoides obsoletus group Meigen, Culicoides pulicaris Linnaeus and Culicoides newsteadi Austen were present at over 50% of sites. However, the spatial distribution of C. imicola showed the closest correspondence to that of the 2000 and 2001 bluetongue (BT) outbreaks and its presence and abundance were significant predictors of the probability of an outbreak, suggesting that it was the main vector during these years. Although C. imicola may have played a role in transmission in several sites near Paternó, it was absent from the majority of sites at which outbreaks occurred in 2002 and from all sites in the province of Messina. All three potential novel vectors were widespread across sites at which outbreaks occurred during 2002. Of these, C. newsteadi was an unlikely candidate, as it was significantly less prevalent in outbreak vs. non-outbreak sites in Messina. It is hypothesized that the yearly distribution and intensity of outbreaks is directly attributable to the distribution and abundance of the vectors involved in transmission during each year. When C. imicola operated as the main vector in 2000 and 2001, outbreaks were few in number and were restricted to coastal regions due to low abundance and prevalence of this species. In 2002, it is hypothesized that BTV transmission was handed over to more prevalent and abundant novel vector species, leading to numerous and widespread outbreaks and probably to overwintering of the virus between 2001 and 2002. Based on catch ranges in outbreak vs. non-outbreak sites, it is tentatively suggested that nightly catches of 400 or more C. obsoletus and 150 or more C. pulicaris allow BTV transmission at a site, and provide a strategy for a fuller examination of the relationship between BTV transmission and the abundance and distribution of different vector species. [source] Summer activity patterns of nocturnal Scarabaeoidea (Coleoptera) of the southern tablelands of New South WalesAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 1 2007Martin J Steinbauer Abstract, Australia has a rich diversity of Scarabaeoidea; however, little is known about the majority of them. Because adults of Anoplognathus, Automolius, Heteronychus, Heteronyx and Liparetrus in particular are reliant upon eucalypts, a number of bluegum plantation companies supported the commencement of research into the biology and ecology of scarabs of economic significance to them. Consequently, it was decided that the occurrences of species endemic to this area would be studied and it was assumed that information on the nocturnal species in the aforementioned genera would be obtained. From late November 2003 until late February 2004, the abundances of Scarabaeoidea caught in two light traps that partition insects caught on a given night into seven time periods each of 1.75 h duration were recorded. A total of 48 263 scarabs representing 21 genera were caught. Within the 14 species caught most often, six types of summer activity pattern were apparent: late spring to early summer (Australobolbus gayndahensis), early to mid-summer (Scitala sericans), mid-summer only (Sericesthis ignota), mid- to late summer (Acrossidius tasmaniae, Aphodius lividus, Heteronyx chlorotica, Het. praecox and Antitrogus morbillosus), late summer only (Ataenius picinus) and all summer (Anoplognathus pallidicollis, Phyllotocus macleayi, Sericesthis geminata, Ser. micans and Ser. nigrolineata). Abundances of nine species peaked between 21:30 and 23:15 h (Aph. lividus, Phy. macleayi, Het. chlorotica, Sci. sericans, Ser. geminata, Ser. micans, Ser. nigrolineata and possibly also Ant. morbillosus), three were most abundant between 19:45 and 21:30 h (Ano. pallidicollis, Ser. ignota and possibly also Ata. picinus), another two were most abundant from 19:45 to 23:15 h (Acr. tasmaniae and Het. praecox) and Aus. gayndahensis was most abundant between 23:15 and 01:00 h. Of course, it is not just a knowledge of the identity of the species and the timing of their occurrence that are important when making insect management decisions, but also the size of population needed to inflict economically significant loss. It is now beholden upon bluegum plantation companies to support further research to determine the relationships between light trap catches of eucalypt-feeding scarabs, tree age and/or size and level of defoliation in order to improve their confidence in this method of monitoring over ground surveys. [source] | ||||||||||