Annual and spatial activity of dung flies and carrion in a Mediterranean holm-oak pasture ecosystem

Abstract

The annual activity and spatial distribution of Muscidae and Calliphoridae were investigated in a holm-oak (“dehesa”) ecosystem in western Spain over two years using wind-oriented traps baited with a mixture of fresh cattle faeces, liver and sodium sulphide solution. Lucilia sericata (Meigen) was always the dominant species and, with Chrysomya albiceps (Weidemann), Hydrotaea ignava (Harris), Muscina levida (Harris) and Muscina prolapsa (Harris), was more abundant during the second than the first year. By contrast, Calliphora vicina Robineau-Desvoidy, Calliphora vomitoria (L.), Hydrotaea armipes (Fallén), Hydrotaea penicillata (Rondani) and Hydrotaea dentipes (Fabricus) were more numerous during the first than the second year of the study. In summer, the diptera sampled flies were significantly more abundant in a wooded area than a pasture area. However, in autumn, while H. penicillata remained significantly more abundant in woodland, L. sericata became more abundant in the pasture, whereas C. vicina was captured in open and wooded areas in similar proportions. During winter and spring the populations of sampled were relatively small. The changing patterns of abundance are discussed in relation to diffrences in climate within and between years.