A Review of the Natural History and Laboratory Culture Methods for the Yellow Dung Fly,Scathophaga stercoraria

Abstract

The yellow dung fly Scathophaga stercoraria (L.) (Diptera: Scathophagidae) is a widespread and locally abundant fly associated with the dung of large mammals, especially farm animals. This species has recently become a standard test organism for evaluating toxic effects of veterinary pharmaceuticals in livestock dung. In this context, a review of its natural history and a general description of the field and laboratory rearing methods of this species are provided here to benefit the scientific community as well as government regulators and applicants of eco-toxicological studies. For guidance, means and ranges are included for all relevant standard life history traits stemming from previously published data on Swiss populations.

The Effect of Fluctuating Temperatures During Development on Fitness-Related Traits ofScatophaga stercoraria(Diptera: Scathophagidae)

“…The expression of standard life-history traits (body size, development time, growth rate, and mortality) of the yellow dung ßy has been well investigated across a wide thermal range using constant temperatures (Blanckenhorn 1997b, Blanckenhorn et al 2010. The effects of ßuctuating temperatures have not been studied in much detail despite the potentially high thermal variability associated with its juvenile habitat, except for at low temperature (Blanckenhorn 1997a).…”

“…We cannot exclude that smaller body size at maturity may be advantageous if activity is primarily conÞned to the high end of the temperature scale. Nevertheless, the summer decline of yellow dung ßy populations in Central European habitats strongly suggests that the ßies remain inactive during these periods or at least do not engage much in reproductive activities during hot spells (Blanckenhorn et al 2001, Blanckenhorn et al 2010.…”

“…The response to developmental temperature ßuctuations, however, did not differ between the sexes even though the shapes of the reaction norms of the constant temperature treatments were quite different (curvilinear and linear, respectively). The large lifespan difference found (only) at low developmental temperatures could potentially be explained by sex speciÞc sensitivity and/or age-dependence in reacting to lacking protein sources, which are required for both sexes for the production of sperm and eggs (Blanckenhorn et al 2010). Males lived longer than females in a study where prey was provided in addition to sugar (Blanckenhorn 1997b).…”

“…Furthermore, 12ЊC is at the lower limit at which yellow dung ßies show direct egg-to-adult development (as opposed to pupal winter diapause), and temperatures beyond 24ЊC show strong negative effects (Ward andSimmons 1990, Blanckenhorn et al 2001). Before the experiment ßies were propagated for Þve generations at standard laboratory conditions (constant 18ЊC, a photoperiod of 16:8 [L:D] h cycle, and 50% relative humidity [RH]) (Blanckenhorn et al 2010). The experiment was initiated by setting up 11 pairs for mating and subsequent egg laying.…”

“…The yellow dung ßy, Scatophaga stercoraria (L.), is an important decomposer of the dung of livestock (Blanckenhorn et al 2010). A thorough understanding of how environmental variation affects its abundance is therefore instrumental and economically relevant.…”