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directly underneath the pats, which are hollowed out from within. Some large species
originating from France excavate tunnels to a depth of approximately 30 cm below the
dung pat. These beetles make sausage-shaped brood chambers along the tunnels. The
shallowest tunnels belong to a much smaller Spanish species that buries dung in
chambers that hang like fruit from the branches of a pear tree. South African beetles
dig narrow tunnels of approximately 20 cm below the surface of the pat. Some
surface-dwelling beetles,
including a South African species, cut perfectly-shaped balls
from the pat, which are rolled away and attached to the bases of plants.
For maximum dung burial in spring, summer and autumn, farmers require a variety of
species with overlapping periods of activity. In the cooler environments of the state of
Victoria, the large French species (2.5 cms long), is matched with smaller (half this
size), temperate-climate Spanish species. The former are slow to recover from the
winter cold and produce only one or two generations of offspring from late spring until
autumn. The latter, which multiply rapidly in early spring, produce two to five
generations annually. The South African ball-rolling species, being a sub-tropical
beetle, prefers the climate of northern and coastal New South Wales where it
commonly works with the South African tunneling species. In warmer climates, many
species are active for longer periods of the year.
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