Summary
This paper presents a review of research conducted during the past two decades on the biology and ecology of L. cuprina. It highlights several areas where further research is merited. The more important of these include: information on the factors that regulate the time of onset of pre-pupal overwintering; data on the factors that regulate juvenile survival both on the sheep and in the soil; information on the relative importance of carrion and sheep faeces as sources of adult protein, particularly in the more arid parts of the species range; and the elucidation of the relative importance of carrion and live sheep as Lucilia oviposition sites. It concludes that sufficient is now known about the life-cycle of L. cuprina to enable the completion of a weather-driven simulation model developed by the Late WG Vogt. By modelling existing field data, we may be able to anticipate many of the existing gaps in our knowledge of the species biology. The model may also indicate knowledge gaps of which we are currently unaware.
 
 

Summary
The number of Lucilia cuprina to successfully reproduce from brushtail possum carcasses in Tasmania exposed to oviposition in summer and autumn represented less than 0.6% of the total fly-strike population to emerge. Similarly, the total number of this species to emerge from the carcasses of sheep that had suffered fly-strike prior to death during the summer months accounted for only 4.2% of emerging fly-strike numbers. In contrast, carcasses offer a significant resource for maintaining field populations of L. sericata, Calliphora stygia and Chrysomya rufifacies. In possum carcasses available for fly oviposition in late summer, significantly more C. stygia and Ch. rufifacies emerged than L. sericata or L. cuprina. When oviposition was made available in possum carcasses during autumn, L. sericata and C. stygia emerged in much higher numbers than L. cuprina, and dominated carcasses until the appearance of the secondary Ch. rufifacies . In sheep carcasses, Ch. rufifacies was the most abundant fly-strike species to emerge. Possum and sheep carcasses appear to be of little importance for maintaining populations of L. cuprina during late summer and early autumn. However, for the control of other fly-strike species and to reduce the possibility of overwintering populations contributing to initial populations of L. cuprina in the following spring, carcasses exposed in late autumn may need to be managed to prohibit potential fly breeding.
 
 

Summary
This paper presents a brief review of the factors affecting flystrike as background to the on-going analysis of information on strike incidence, flock management, weather conditions and fly abundance in three discrete sheep grazing areas in eastern Australia (Flinders Island, Gunning and Inverell). These data were assembled in the late 1980s – early 1990s as part of a programme aimed at developing a strike management model. The information was supplied on a weekly basis over a period of 3-4 years by 30-40+ graziers in each study area. Weather and fly abundance was monitored weekly in each area in conjunction with a questionnaire survey that provided information on flock size, drenching practice, crutching, shearing and dagging,, numbers of animals checked for strike, numbers struck in each age class and the type and method of insecticide usage.

Previous studies have assessed strike incidence on the basis of the numbers of animals reported struck, relative to the number of animals checked. The latter figure invariably includes sheep that, by reason of recent management (e.g. shearing, crutching or jetting), are not susceptible to strike. The extent to which this procedure imparts an overall bias in estimates of regional strike is not known, but its effect, between weeks, at the level of the individual farm, is often quite dramatic(e.g. strike incidence before and after jetting may vary from 20% to 0%). Hence, in order to properly assess inherent effects due to weather and fly abundance, these potentially confounding management influences need to be removed from the data set prior to analysis. This paper describes the procedures being used to enable weekly estimates of strike in each of the three study areas, to be computed relative to the number of potentially susceptible sheep rather than on the basis of the total number of sheep inspected.
 
 

Summary
The aims of this study were to examine the overwintering behaviour of L. cuprina and to use these results to develop a predictive model for spring emergence. In the colder areas of its range, this species is known to remain dormant in the soil in the post feeding larval stage until the following spring. This study has shown that the mechanism of dormancy is a facultative diapause and this overwintering strategy can be flexible. Lucilia cuprina has the ability to keep developing into winter if temperatures are warm enough and spring emergence can vary from year to year, depending on temperatures experienced in the colder months. Although this study was unable to present a final model to predict emergence in the field it was able to determine the deficiencies in available data at present and test some of the models available in the literature. The best non-linear model tested in this study was the matched-asymptotic model ("Equation 6") derived by Hilbert and Logan (1983).
 
 

Summary
Knowledge of the biology of the target pest is essential to the design of efficient control programs. However, information is lacking on many important aspects of the basis biology of sheep lice (Bovicola ovis) despite recommendations of the need for research in this area from past workshops. In this paper we summarise some of the more recent information on transmission and population dynamics of sheep lice and discuss implications for control. We also describe factors which may regulate these processes and highlight some specific areas in which information is required.
  

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