The effect of seasonal changes in cattle dung on egg production by two species of dung beetles (Coleoptera: Scarabaeidae) in south-western Australia

Abstract

Egg production by two scarabaeine dung beetles, Onthophagus binodis

Stages of bush fly, Musca vetustissima (Diptera: Muscidae), killed by scarabaeine dung beetles (Coleoptera: Scarabaeidae) in unfavourable cattle dung

“…There was a density effect on Onitis alexis egg production. These figures vary from 1.8 to 0.006 eggs per female per pad, which is very low, as would be expected in unfavourable dung (Ridsdill-Smith, 1986). Onitis alexis was estimated to bury 60% of the pad at low densities and 35% at high densities, whereas Onthophagus binodis buried 4% at low densities and 3% at high densities.…”

“…Quality tends to be favourable for breeding with the fly M. vetustissima, and dung beetles Onthophagus binodis Thunberg and Onitis alexis Klug in spring and unfavourable in summer in regions with Mediterranean-type climates. Rate of oviposition by Onthophagus binodis and Onitis alexis is high in favourable dung and low in unfavourable dung (Ridsdill-Smith, 1986). Fewer M. vetustissima oviposit on unfavourable than favourable dung (Ridsdill-Smith & Hayles, 1989), but their main response is that adults emerging from larvae that have fed on unfavourable dung are smaller than those from favourable dung (Matthiessen & Hayles, 1983;Ridsdill-Smith & Hayles, 1989;Sands & Hughes, 1987).…”

“…When beetles arrive at dung at the time flies oviposit, fewer larvae hatch or survive than when beetles arrive one day later, and presumably the beetles kill M. vetustissima eggs (Hughes etal., 1978;Ridsdill-Smith et a\., 1987). When Onthophagus gazella Fabricius and Onthophagus binodis reduce fly numbers, emerging survivors are sometimes stunted, and presumably the beetles kill older M. vetustissima larvae (Bornemissza, 1970;Ridsdill-Smith et a\., 1986). Ridsdill-Smith et al (1986) suggest that Onthophagus binodis probably causes mortality mainly to M. vetustissima eggs in favourable dung, and to older larvae in unfavourable dung.…”

“…When Onthophagus gazella Fabricius and Onthophagus binodis reduce fly numbers, emerging survivors are sometimes stunted, and presumably the beetles kill older M. vetustissima larvae (Bornemissza, 1970;Ridsdill-Smith et a\., 1986). Ridsdill-Smith et al (1986) suggest that Onthophagus binodis probably causes mortality mainly to M. vetustissima eggs in favourable dung, and to older larvae in unfavourable dung.…”

Dung beetles (Coleoptera: Scarabaeoidea) in three landscapes in Mato Grosso do Sul, Brazil

“…In some environments, it is possible to see differences in the abundance and biomass of beetles in open areas, compared with forests (Lumaret and Kirk, 1987). However, the presence and permanence of Scarabaeoidea in different environments are related to several other factors (Ridsdill-Smith, 1986), because this community has demonstrated sensitivity to changes imposed on the environment (Durães et al, 2005).…”