Musca Vetustissima Research Articles

Estimating biocontrol agent spread: A case study using introduced dung beetles

Abstract Insect biological control agents may be released in relatively few locations; thus, the rate of spread is critical to predicting the spatial distribution of the agent. Exotic dung beetles have been introduced into Australia since the 1960s to bury dung, reduce bush fly populations, increase pasture productivity and improve livestock health. We use a stochastic cellular automata model to predict the historical occupancy and abundance of introduced dung beetles in the South West agricultural region of Western Australia. The model predicts the spread of four species of dung beetles in six‐month time steps for 10 years following initial release. Our model includes release locations, species‐specific ecological parameters, dung resource availability and weather variables. The average rate of spread varied between species from a high of ca. 79 km/year (Euoniticellus intermedius) to a low of 28 km/year (Onthophagus taurus). Thus, after 10 years, the area of spread varied between 99,175 and 34,175 km2 and abundance varied from 88,100 to 4,189 beetles/km2. These findings provide an estimate of the spread patterns of dung beetles. The model can be used to guide future dung beetle release programmes in Australia and elsewhere.

Chasing Flies: The Use of Wingbeat Frequency as a Communication Cue in Calyptrate Flies (Diptera: Calyptratae).

Simple SummarySome of the fastest and most agile flying insects are the calyptrate flies which include blow flies, flesh flies, and house flies. The current study compared the wingbeat frequency of four species, representing four genera of these flies, recorded in free flight and analyzed using sound editor and analysis software. Wingbeat frequency was found to differ between the four species and between sexes. Such findings provide insight into how flies are communicating and show promise for the use of wingbeat frequency as a novel methodology to identify fly specimens.The incidental sound produced by the oscillation of insect wings during flight provides an opportunity for species identification. Calyptrate flies include some of the fastest and most agile flying insects, capable of rapid changes in direction and the fast pursuit of conspecifics. This flight pattern makes the continuous and close recording of their wingbeat frequency difficult and limited to confined specimens. Advances in sound editor and analysis software, however, have made it possible to isolate low amplitude sounds using noise reduction and pitch detection algorithms. To explore differences in wingbeat frequency between genera and sex, 40 specimens of three-day old Sarcophaga crassipalpis, Lucilia sericata, Calliphora dubia, and Musca vetustissima were individually recorded in free flight in a temperature-controlled room. Results showed significant differences in wingbeat frequency between the four species and intersexual differences for each species. Discriminant analysis classifying the three carrion flies resulted in 77.5% classified correctly overall, with the correct classification of 82.5% of S. crassipalpis, 60% of C. dubia, and 90% of L. sericata, when both mean wingbeat frequency and sex were included. Intersexual differences were further demonstrated by male flies showing significantly higher variability than females in three of the species. These observed intergeneric and intersexual differences in wingbeat frequency start the discussion on the use of the metric as a communication signal by this taxon. The success of the methodology demonstrated differences at the genus level and encourages the recording of additional species and the use of wingbeat frequency as an identification tool for these flies.

Ecosystem services provided by dung beetles in Australia

Although there are nearly 500 species of native dung beetles in Australia, most are adapted to small, hard, dry, pelletised marsupial droppings and not to dealing with the large, moist deposits of cattle. In 1788, Governor Arthur Phillip arrived at Botany Bay with five cows, two bulls, 44 sheep and seven horses: this signalled major changes in Australia. Now there are about 27 million cattle, whose annual dung production has a dry matter content of about 42 million tonnes. Until CSIRO introduced exotic dung beetles in the 1960s, the dung of these herbivores sat on the soil surface, sometimes for years, locking up organic matter, smothering pasture and polluting waterways. CSIRO introduced 53 exotic dung beetle species, of which 43 were released to the Australian mainland between 1965 and 1985. Twenty-three of these have become established, many of which have reached the natural limits of their distribution. I consider the reason for the failure of the other 30 species to establish and briefly review previous contributions to examining the role of dung beetles in delivering ecosystem services, noting that much of the published literature concerns laboratory studies. New field data are then examined on the way in which introduced species are transforming dung communities and the ecosystem services they provide. The capacity of deep-tunnelling dung beetles to transform the soil profile is examined along with their effects on pasture production and the flow of nutrients from dung on pasture. The biocontrol capacity of dung beetle activity is considered in relation to the native bush fly, Musca vetustissima, the introduced buffalo fly, Haematobia irritans exigua, and dung-borne intestinal parasites (helminths and Cryptosporidium). The rationale for introducing additional species to Australia is considered.

Predicting nuisance fly outbreaks on cattle feedlots in subtropical Australia

Flies are important arthropod pests in intensive animal facilities such as cattle feedlots, with the potential to cause production loss, transmit disease and cause nuisance to surrounding communities. In the present study, seasonal population dynamics of three important nuisance flies, namely house flies (Musca domestica L.), bush flies (M. vetustissima Walker) and stable flies (Stomoxys calcitrans L.) (Diptera: Muscidae), were monitored on cattle feedlots in south-eastern Queensland, Australia, over 7 years. Musca domestica was by far the dominant species, comprising 67% of the total flies trapped. Models were developed to assess the relationship between weather parameters and fly abundance and to determine whether population trends could be predicted to improve the timing of control measures. For all three species, there were two main effects, namely time-of-year (mainly reflected by minimum temperatures and solar radiation) and rainfall. The abundance of all three species increased with increasing temperature and rainfall, reaching a peak in summer, before decreasing again. Rainfall events resulted in significantly elevated numbers of M. domestica for up to 5 weeks, and for 1 week for M. vetustissima. Peak fly numbers were predicted by the model to occur in spring and summer, following 85–90-mm weekly rainfall. The population dynamics of S. calcitrans were least influenced by rainfall and it was concluded that weather variables were of limited use for forecasting stable fly numbers in this environment and production system. The models provide a useful tool for optimising the timing of fly-control measures, such as insecticide or biopesticide applications, adding to the efficiency of integrated control programs.

The Role of Males in Host-Fruit Selection by Females of a Walnut Infesting Tephritid (Diptera) Rhagoletis zoqui

Rhagoletis zoqui Bush flies have a mating system in which males guard and defend walnut fruit-hosts from other males and mate, apparently without courtship, with females as they arrive to oviposit. Hypothetically, female selection of a particular fruit may be due to the quality of fruit for larval development (previously determined by guarding males), the quality of the male upon the fruit as a mate, or both, but this is not clear. We performed an experiment to determine if R. zoqui females or males select the fruit to oviposit or guard based on its quality for larval development (i.e., size, sugar-content [brix] or hardness), or following male-mediated cues such as chemical residues, related to prior fruit occupation by the male during guarding. Fruit choice by R. zoqui females and males were examined under semi-natural conditions on caged branches of English walnut trees, Juglans regia L., growing in the highlands of south-central Mexico. A single male or female was allowed to select a fruit and was then removed. An individual of the opposite sex was then introduced to the same branch and presented with the opportunity to choose among the same array of hosts. The pattern of fruit choice was consistent, with female choice on the basis of male presence, suggesting that males left a chemical cue that persisted in their absence. No fruit quality differences were detected between selected and non-selected fruit. Fruit features selected by females and males matched almost exactly, although males rarely select the same fruit as females. We conclude that females preferentially selected fruit previously occupied by males although additional studies are required to determine the cues used by R. zoqui for oviposition resource selection by both females and resource guarding males.

Temporal and spatial trends in adult nuisance fly populations at Australian cattle feedlots

AbstractA comprehensive trapping program to determine the species composition, seasonality and distribution of adult nuisance fly populations at a southern Queensland feedlot was conducted from 2001 to 2003. Short‐term information on nuisance fly populations was also collected from two feedlots located in other climatic regions. Twenty‐five species of Diptera were identified. The more commonly trapped species were the house fly, Musca domestica L. (Muscidae) (38%), the hairy maggot blowfly, Chrysomya rufifacies (Macquart) (Calliphoridae) (27%) and the bush fly, Musca vetustissima Walker (Muscidae) (15%). Seasonal effects were the major determinant of fly populations. All commonly trapped fly species had low abundance during the coldest winter months, July and August. Musca domestica had one annual, broad peak in abundance starting in spring and extending over about 8 or 9 months. Musca vetustissima had a major abundance peak in October/November and a smaller peak around April. Stomoxys calcitrans (L.) (stable fly) (Muscidae) showed two annual peaks in abundance, with the major peak in May. Chrysomya spp. were most abundant during spring, summer and autumn, whereas the highest numbers of Calliphora augur (F.) (blue‐bodied blowfly) (Calliphoridae) were trapped in winter.The sites within the feedlot with the highest catches of M. domestica were the feed mill, cattle pens and the hospital area and of S. calcitrans the manure piles, silage pits and the feed mill. The lowest catches of M. domestica and S. calcitrans were obtained in the traps situated a few kilometres outside the feedlot. In contrast, M. vetustissima and blowfly catches were higher in outside traps and traps near the manure piles than any other feedlot site.There was a correlation between the animals' number of fly avoidance movements and M. domestica catches and between the number of leg stomps and stable fly catches, respectively.

The Muscidae (Diptera) of Vanuatu

The Muscidae of Vanuatu are reviewed. All the genera and recorded species are diagnosed and an identification key is given. The work was carried out in the Muséum national d’Histoire naturelle (Paris, France), where material belonging to that museum and also a large collection from the Bishop Museum (Honolulu, USA) were studied. A total of 35 species, 4 of them endemic, were recognized, including two species newly described, Dichaetomyia univittata, sp. nov. and Parvisquama vanuatuensis, sp. nov. The following genera are recorded for the first time: Cephalispa Malloch, Coenosia Meigen, Helina Robineau-Desvoidy, Lispocephala Pokorny, Musca Linnaeus and Stomoxys Geoffroy. The following species are recorded for the first time: Atherigona punctata Karl, Cephalispa commoni (Paramonov), Coenosia pumilio Stein, Helina flavoextrema Couri, Pont & Daugeron, Limnophora longiantennata Couri, Pont & Daugeron (male described for the first time), Lispe nicobarensis Schiner, Lispocephala pectinata (Stein), Musca domestica Linnaeus, Musca ventrosa Wiedemann, Musca vetustissima Walker and Stomoxys calcitrans (Linnaeus). A brief discussion on the composition of the fauna is also presented.

The Muscidae (Diptera) of New Caledonia

The Muscidae of New Caledonia are reviewed. A key for the identification of genera and species is given, together with diagnoses, descriptions and illustrations. The revision is based on literature records and on examined material from New Caledonia deposited in various museums and institutions. A total of 18 genera and 40 species are recognised, 7 of which are endemic and 4 of which are newly described: Dichaetomyia shinonagai, sp. nov.; Helina flavoextrema, sp. nov.; Limnophora longiantennata, sp. nov. and Pygophora spinifera, sp. nov. Helina Robineau-Desvoidy, Synthesiomyia Brauer & Bergenstamm and Neomyia Walker are newly recorded genera, and Atherigona bidens Hennig, Atherigona poecilopoda Bezzi, Lispe fuscipalpis Malloch, Lispocephala occulta (Pont), Musca ventrosa Wiedemann, Musca vetustissima Walker, Neomyia timorensis (Robineau-Desvoidy), Pygophora hopkinsi Malloch and Synthesiomyia nudiseta (Wulp) are newly recorded species for New Caledonia. Four species previously recorded in the literature on New Caledonia, Muscina stabulans (Fallén), Lispe assimilis Wiedemann, Pygophora maculigera (Stein) and Pygophora minuta Malloch, were not represented in the material examined. The male terminalia of the Atherigona species, Pygophora caledonica (Bigot) and the new species are illustrated. Coenosia pumilio Stein is redescribed. Lispe binotata Becker, 1914 is a new junior subjective synonym of Lispe nicobarensis Schiner, 1868, syn. nov. A brief discussion on the composition of the fauna is also given.

The Australian Bush Fly (Musca vetustissima) as a Potential Vector in the Transmission of Foodborne Pathogens at Outdoor Eateries

Abstract Australian outdoor activities are often accompanied by a barbeque (BBQ) with family, friends, and guests, which are often interrupted by uninvited guests in the form of the Australian bush fly, Musca vetustissima. We investigated the bacterial loading associated with the Australian bush in three different environments: on a cattle farm, in a typical urban area (shopping center car park), and at a BBQ. The highest bacterial populations per fly were found to occur in a farm environment ( approximately 9.1 x 10(4) CFU per fly), whereas the bacterial population was lowest on flies caught in an urban environment ( approximately 1.9 x 10(4) CFU per fly). The median CFU per fly caught near a BBQ was approximately 5.0 x 10(4). Escherichia coli was the most commonly isolated potential pathogen, whereas Shigella sp. was the least common bacterial isolate that was screened. All isolated foodborne pathogens or indicator bacteria were screened for antibiotic resistance against commonly prescribed antibiotics. This revealed a very high prevalence of multidrug resistance, especially among the Salmonella and Shigella isolates of 94% and 87% resistance, respectively, against amoxicillin, roxythromycin and cefaclor.

Development of Melaleuca oils as effective natural‐based personal insect repellents

AbstractFor many decades effective insect repellents have relied on synthetic actives such as N,N‐diethyl‐meta‐toluamide. Increasingly, consumers are seeking natural‐based alternatives to many everyday products including insect repellents. While many studies have been published detailing the potential of essential oils to act as insect repellents, few oils have been identified as viable alternatives to synthetic actives. This study details the process involved in the selection of Australian essential oils effective as repellents and the subsequent testing of natural‐based insect repellents using the selected oils. Using a combination of laboratory‐based and field‐based testing, oil from Melaleuca ericifolia was identified as being an effective insect repellent. When formulated into three different bases: an alcohol‐based spray, an emulsion and a gel, these Melaleuca‐based repellents were shown to be as effective at repelling mosquitoes Aedes vigilax (Skuse) (Diptera: Culicidae) and Verrallina carmenti (Edwards) (Diptera: Culicidae), the bush fly Musca vetustissima (Walker) (Diptera: Muscidae), and biting midges Culicoides ornatus (Taylor) (Diptera: Ceratopogonidae) and Culicoides immaculatus (Lee & Reye) (Diptera: Ceratopogonidae) as a synthetic‐based commercial repellent. This study has shown that effective insect repellents based on natural active ingredients can deliver repellency on par with synthetic actives in the field. Three Melaleuca‐based formulations have been registered as repellents and are now commercially available.

On the population dynamics of the Australian bushfly

Each spring, the Australian bushfly (Musca vetustissima Walker) migrates from its over-wintering areas located in central Australia and repopulates the south-eastern parts of the continent. In this paper, a simple size-structured model, in the form of a reaction–advection equation with delay, is presented for the evolution of the population density of the bushfly. The model takes into account the important role of cattle dung in its life cycle and includes the effects of wind-borne migration. Bifurcation analyses of the model equations in the absence of wind advection reveals the environmental conditions under which the fly population will die out, reach a stable equilibrium or explode. Numerical simulations which include advection reveal the importance of wind-borne migration in building up the population of flies in south-eastern Australia during the summer months.

Evidence for insect transmission of rabbit haemorrhagic disease virus.

The spread of rabbit haemorrhagic disease (RHD) virus from quarantine on Wardang Island to mainland Australia in 1995 suggested that insects could be potential vectors. Field observations and laboratory experiments were conducted to address aspects of this hypothesis. Firstly, the variation in insect populations on the island during the field trials was examined. There was approximately a 1,000-fold increase in the number of bushflies, Musca vetustissima, shortly before the spread of the virus. Secondly, M. vetustissima were tested in the laboratory as potential vectors of RHD virus, and it was demonstrated that disease could be transmitted between rabbits by flies. Finally, 13 of 16 insect samples, collected from Wardang Island and from several sites on the mainland following the spread of virus off the island, were positive for the presence of RHD virus by a specific polymerase chain reaction (PCR). Only one sample contained sufficient infectious virus to kill a susceptible rabbit. These data, combined with previously published information on fly biology, suggested that flies, particularly bushflies, may be involved in the transmission of RHD virus. Other possible routes of spread were not assessed in this study.

Seasonal variation in trachoma and bush flies in north-western Australian Aboriginal communities.

Among younger age groups trachoma (Chlamydia trachomatis) has been identified as a major cause of morbidity in Australian Aboriginal communities. North-western Australia has two seasons, referred to as the wet and the dry, and until recently most trachoma screening programmes were conducted during the dry season. This study compared the prevalence of trachoma between three Aboriginal communities, two in the west and one in the east Kimberleys with differences in adult bush fly (Musca vetustissima) populations between the wet and dry seasons. All preschool and school-aged children in each community were screened for trachoma in February and July 1996 using the World Health Organization method for clinical assessment of trachoma. Flies were trapped fortnightly from September through to May (inclusive) using a wind-orientated fly trap. Two communities in the west Kimberleys had a significantly higher rate of trachoma during the wet season (14-59% in dry season compared with 46-69% in wet season). One community showed no difference but this was probably due to the reduced re-screening rate. Further-more, it was demonstrated that fly populations are so low during the dry season that they were untrappable; however, populations of bush fly significantly increased during the wet season (ranging from 6 to 146 flies per hectare per month). If bush fly populations are correlated with increased levels of trachoma, then measures aimed at augmenting public health plans for bush fly control may decrease the cross-infection rate. Additionally, based on the results of this study, wet season trachoma screening trips should be considered.

Japan set to endorse Kyoto Protocol as Bush flies in

Japan set to endorse Kyoto Protocol as Bush flies in

Quantitative aspects of the regulation of ovarian development in selected anautogenous Diptera: integration of endocrinology and nutrition

AbstractAspects of the influence of nutrition on the degree of ovarian development in selected anautogenous Diptera are reviewed. The Diptera considered are several mosquito species, with emphasis on Aedes aegypti, the house fly, Musca domestica, the Australian bush fly, M. vetustissima and the blowflies, Lucilia cuprina and Phormia regina. All the selected species display discrete ovarian cycles in which all oocytes destined to reach maturity in a particular ovarian cycle develop synchronously. In these species, the proportion of females maturing oocytes and, where such data exist, the number of oocytes they mature are positively correlated with the amount of any particular nitrogen‐containing material ingested or given by enema or by infusion. In addition, the degree of ovarian development may be affected by the chemical composition of nitrogen‐containing food. Possible physiological bases for the observed relationships are discussed. Available evidence suggests that whether or not a female matures any oocytes is hormonally regulated and that the number of oocytes matured is probably regulated by the availability of nutrients. Some approaches that might further elucidate the physiological regulatory mechanisms involved in ovarian development are outlined.

Size and sex of floral displays affect insect visitation rates in the dioecious Australian alpine herb, Aciphylla glacialis

Differences in floral display size between male and female plants in dioecious species are often considered to be the result of competition within and between male and female plants to attract insects, although this hypothesis is rarely tested. In a field study of the alpine dioecious herb Aciphylla glacialis, insect visitation rates were found to increase with increasing floral display, as predicted. Dipterans were the most common visitors to male and female inflorescences, both in terms of individuals visits (2083 out of 2581 total visits by insects), and species number (20 morphospecies, potentially 22 species). Larger male inflorescences attracted 1.7 times as many insects in total, and 3.1 times more visits by the most common flower visitor, Musca vetustissima than did female inflorescences, but equal number of visits by the next most common flying visitors, Poecilohetaerus aquilius and Tephritis poenia. There was no difference in the amount of time M. vetustissima individuals spent on male and female inflorescences, even though male inflorescences have more flowers. Larger displays (four and eight inflorescences) of either sex attracted more visits than smaller ones (one inflorescence), although the rate of increase in visitation rate with increasing floral display declined. The response of insects to increasing floral display does not support the predicted escalating or proportionate increasing rate of visitation of some models for the evolution of dimorphism in floral displays in dioecious plants.

The development and survival of three species of coprophagous insect after feeding on the faeces of sheep treated with controlled‐release formulations of ivermectin or albendazole

To assess the toxicity from residues of controlled-release formulations of ivermectin and albendazole to insects that feed on sheep faeces. In two consecutive years, groups of sheep were treated with controlled-release capsules of ivermectin or albendazole. Untreated sheep were used as controls. Larvae of the bush fly, Musca vetustissima, and adults and larvae of the dung beetles, Onthophagus taurus and Euoniticellus fulvus were fed on faeces collected at intervals after drug treatment. In assays using beetles, treatment effects were assessed by comparing numbers of eggs laid, survival of juveniles and survival of mature and immature adults. Survival at time of pupariation was used in assays on flies. Faeces from sheep treated with albendazole had no detectable effects on breeding by either flies or beetles. In contrast, faeces voided by sheep treated with controlled-release capsules of ivermectin (CRI) precluded successful breeding by each of the species tested. No fly larvae and almost no beetle larvae survived in faeces collected up to 39 days after capsule administration. Newly-emerged O taurus also suffered significant mortality whereas those that survived underwent delayed sexual maturation. Ivermectin residues had no effect on the survival of sexually mature beetles, but reduced the fecundity of O taurus. A model simulating the effects of drug residues on dung beetle populations indicates that CRIs have the potential to cause substantial declines in beetle numbers, particularly if treatment coincides with spring emergence.

Honeybee pollination of buckwheat (Fagopyrum esculentum Moench) cv. Manor

The role of honeybees (Apis mellifera) in the pollination of buckwheat cv. Manor was studied in a commercial planting at Smeaton, Victoria. Honeybees comprised 80% of all insect visitors to this crop. Other insects included ladybirds (Coccinella transversalis and C. undecimpunctata), hoverflies (Meangyna viridiceps), drone flies (Eristalis sp.), blowflies (Calliphoridae), cabbage white butterflies (Pieris rapae), small bush flies and native bees. The activity of honeybees and other insects increased seed production from 91.5 g/plot (plots closed to insects) to 180.4 g/plot (plots open to insects).

Effects of residues of deltamethrin in cattle faeces on the development and survival of three species of dung-breeding insect.

To assess the toxicity to insects of drug residues excreted in cattle faeces following treatment with deltamethrin. Bioassays were performed on one species of dung-breeding fly (Musca vetustissima) and two species of dung beetle (Onthophagus binodis and Euoniticellus fulvus). Cattle on properties near Kangaroo Valley, Canberra and Gundagai were treated with pour-on formulations of deltamethrin. Untreated animals acted as controls. Faeces from treated and untreated cattle were inoculated with newly emerged fly larvae or fed to adults of two species of dung beetle. Percentage survival and duration of development provided measures of the toxicity of deltamethrin residues in faeces. Residues of deltamethrin were excreted in concentrations sufficient to inhibit survival of larvae of M vetustissima for 1 to 2 weeks after treatment. Peak concentrations of 0.4 mg deltamethrin/kg dry weight of faeces occurred 3 days after treatment and were sufficient to kill adult beetles for at least twice this period. With one of two formulations tested, there was evidence of a reduction in dung beetle fecundity and an increase in the duration of juvenile development. A model of the effect of deltamethrin on the breeding success of dung beetles in the field suggests that a single treatment, applied when most of the population is in a nonparous condition, may cause up to 75% reduction in beetle activity by the end of the season. Multiple treatments at 10 or 21 day intervals may drive local populations towards extinction. Depending on the time and frequency of treatment, the effect of deltamethrin on insects in cattle faeces may range from negligible to catastrophic.

Effects of drug residues in the faeces of cattle treated with injectable formulations of ivermectin and moxidectin on larvae of the bush fly,Musca vetustissimaand the house fly,Musca domestica

To assess the toxicity of residues of ivermectin and moxidectin in cattle faeces collected at intervals after treatment. Replicated bioassays of faeces using larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica. Two groups of five Murray Grey x Aberdeen Angus steers were treated with injectable formulations of ivermectin and moxidectin respectively. A third group was used as an untreated control. Newly emerged fly larvae were reared in the dung of treated animals. Drug residues in faeces collected 3 to 35 days after treatment with an injectable formulation of moxidectin had no significant effect on the survival of larvae of M vetustissima. Similarly, faeces dropped up to seven days after treatment caused no significant reduction in larval survival in M domestica. In day 2 dung, residues of moxidectin delayed development of M vetustissima larvae, but had no effect on their survival. In contrast, ivermectin-treated steers, produced dung that inhibited larval development of both M vetustissima and M domestica for 7 to 14 days after treatment. Significant reductions in survival of M vetustissima larvae occurred in dung collected on days 21 and 28 after treatment, but by day 35 survival did not differ from that in control dung. Excreted faecal residues of moxidectin are relatively innocuous to larvae of both M vetustissima and M domestica. Those of ivermectin inhibit survival for 7 to 14 days after treatment and are likely to have adverse effects on non-target organisms.