Table Of ContentCommon dung beetles
in pastures of
south-eastern Australia
Marina Tyndale-Biscoe
4111111~
C S I RO
AUSTRALIA
Division of Entomology
National Library of Australia Cataloguing-tn-Publication Entry
Tyndale-Biscoe. Marina.
Common Dung Beetles in Pastures of South-eastern Australia
ISBN 0 643 050906
1. Dung beetles -Australia. Southeastern.
1. CSIRO. Division of Entomology. II. Title.
caption for front cover figure:
The largest of the introduced dung beetle species.
Geotrupes spiniger.
© CSIRO Australia 1990.
Contents
Acknowledgements ....................................................................................................v
Why were dung beetles brought to Australia? ............................................................. 1
The CSIRO Dung Beetle Project ................................................................................... 1
What does a dung beetle look like? ............................................................................. 1
What do dung beetles do? ............................................................................................. 2
Distribution of dung beetles in Australia .................................................................. 3
Recognition of dung beetles ........................................................................................ 3
The spreading of dung beetles ..................................................................................... 4
Species location maps ................................................................................................ 4
Introduced dung beetles.
Onitis alexis ...................................................................................................6
Onitis aygulus ................................................................................................8
Oniiis pecuarius ........................................................................................... 10
Onitis caifer ................................................................................................. 12
Onitis viridulus ............................................................................................ 14
Euoniiicellus intermedius ........................................................................... 16
Euoniticellus aJricanus ............................................................................... 18
Euoniticellus Julvus .....................................................................................2 0
Euoniticellus pallipes ..................................................................................2 2
Liatongus militaris ......................................................................................2 4
Onthophagus taurus ....................................................................................2 6
Onthophagus binodis ..................................................................................2 8
Onthophagus gazeZZa ....................................................................................3 0
Onthophagus nigriventris ...........................................................................3 2
Sisyphus spinipes ........................................................................................3 4
Geotrupes spiniger .......................................................................................3 6
Hister nomas ................................................................................................3 8
Other beetles commonly found in dung pads ........................................................... 40
Native dung beetles ....................................................................................... 40
Beetles other than dung beetles ................................................................... 41
Maps showing potential and current distributions of species ................................ 47
Map 1 Onitis alexis ...................................................................................4 8
Map 2 Onitis aygulus ................................................................................4 9
Map 3 Onitis pecuarius .............................................................................5 0
Maps showing potential and current distributions of species (continued)
Map 4 Onitis caffer ................................................................................... 51
Map 5 Onitis viridulus .............................................................................. 52
Map 6 Euoniticellus intennedius ............................................................ 53
Map 7 Euoniticellus aJricanus ................................................................ 54
Map 8 Euoniticellus Julvus ......................................................................5 5
Map 9 Euoniticellus pallipes ................................................................... 56
Map 10 Liatongus militaris ....................................................................... 57
Map 11 Onthophagus taurus ......................................................................5 8
Map 12 Onthophagus binodis .................................................................... 59
Map 13 Onthophagus gazella ......................................................................6 0
Map 14 Onthophagus nigriventris ............................................................. 61
Map 15 Sisyphus spinipes ..........................................................................6 2
Map 16 Geotrupes spiniger .........................................................................6 3
Map 17 Hister nomas .................................................................................6 4
Map 18 Onthophagus australis .................................................................. 65
Map 19 Onthophagus gmnulatus ............................................................... 66
Map 20 Onthophagus chepam and Onthophagus posticus ........................ 67
Map 21 Onthophagus auritus and Onthophagus dandalu ......................... 68
Map 22 Onthophagus capella and Onthophagus victoriensis ................... 69
Map 23 Onthophagus pexatus .................................................................... 70
Map 24 Onthophagus pentacanthus and Onthophagus mniszechi.. ......... 71
Detachable map overlay .................................................................. inside back cover
Acknowledgements
The Dairy Research Council and the Australian Meat and Livestock Research
and Development Corporation have, together with CSIRO, funded the publication of
this booklet. I am grateful to Dr R. Sutherst. for generating the potential
distribution maps of the introduced dung beetle species by the use of CLIMEX; to Mr
John Green, for taking the photographs; and to Mrs Sandy Smith and Mr Chris
Hunt for doing all the artwork and generally preparing the manuscript for
publication.
C S I RO
AUST RALIA
Dairy Research Council Division of Entomology Australian Meat and Livestock
Research and Development
Corporation
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eye ~~~
p" \
pronotal lobe or hom
--+----pronotum
wing cover (elytra)
-'----'---'-~-;-~-
hind leg----=;-
Figure 1. Dorsal view of stylised dung beetle
Why were dung beetles brought to Australia?
When Europeans created open pastures and introduced cattle. sheep and horses
into Australia. they produced a new environment which few native dung insects
were able to use. In particular. the dung of cattle was quite different from the
fibrous. pellet-like droppings of native marsupials. Most Australian native dung
beetles are adapted to living in woodlands and have little impact on the soft. moist
dung pads of introduced stock in pastures. Nevertheless. a few native species in
south-eastern Australia can, at times, be found in the dung of cattle and horses.
Their activity is sporadic. however. and they are unable to conSistently bury the
dung produced by the introduced animals.
As a result. pasture pollution with dung. especially in heavily stocked areas,
has become an important environmental and management problem. Undisturbed
dung pads can smother the grass beneath them and promote an unpalatable growth
of rank grass around them. Major fly pests breed in cattle dung: among these are the
blood-sucking buffalo fly infesting cattle in the tropics, and the bush fly, a pest of
man and other animals over most of Australia.
The CSIRO Dung Beetle Project.
In the early sixties Dr G. F. Bornemissza suggested that, to solve this problem,
dung beetles from countries with large. native herbivores be introduced into
Australia. Subsequently, between 1968 and 1982 the CSIRO Division of
Entomology imported over 45 species from Africa. Europe and Asia. Each species
was reared in the laboratory under quarantine conditions for one or more
generations before being released into climatically suitable areas.
The benefits of dung burial are numerous. It cleans up pastures and replaces
nutrients in the soil. Increased water penetration into the soil through beetle
tunnels results in greater water retention and hence less runoff, decreasing soil
erosion. Other benefits include better root penetration and soil aeration. Rapid
dung burial destroys the breeding sites of the fly pests and reduces the free living
stages of gastro-intestinal paraSites of livestock.
What does a dung beetle look like?
Adult dung beetles are insects with a hard outside cuticle. The body has a head, a
pronotum and an abdomen (Figure 1). Three pairs of legs are attached to the ventral
(lower) surface of the body and there are folded wings lying over the dorsal (upper)
surface underneath the wing covers. When not in flight the wings cannot be seen
since the wing covers completely cover them. To fly, the beetles have to lift up the
wing covers, and unfold the wings, which are generally transparent or whitish.
1
What do dung beetles do?
Adults and larvae of dung beetles feed only on dung and therefore are not a
threat to the environment. This is in contrast to some other beetles found in dung
pads, (not dung beetles) which feed on vegetable and other matter besides dung,
while others are carnivorous. The activity of adult dung beetles can break up the
dung pad, and most species bury the dung in the ground for feeding and breeding.
Usually one pair (male and female) work together in digging a nest in the soil under
the pad. They take the dung down and form it into ball- or sausage-shaped objects
called brood masses (Figure 2). Each brood mass contains one to several eggs, each
in a small chamber. The eggs hatch into larvae which feed on the dung within the
brood mass. The larvae grow through three distinct stages called instars, and the
growth rate generally increases with higher temperatures. At the end of the third
instar the larvae cease feeding. and in some species can stop development and stay
inactive for many months. This enables them to survive unfavourable seasonal
conditions. Eventually they change into non-feeding pupae and then into adult
beetles.
The size of the adult beetle remains unchanged throughout life; they do not grow
with age. The newly formed adult beetles dig their way out of the ground and fly to
fresh dung pads in which to feed and breed. The generation length varies with each
species, and there may be one to several generations produced each year.
The adults of most introduced species feed and breed throughout the late spring,
summer and autumn. and die in winter. The larvae overwinter underground. A few
of the introduced species have adults which feed and breed during both autumn and
spring, having spent the winter inactive in the soil. They generally die in summer,
but their larvae survive underground and emerge to form the new generation the
following autumn.
Beetles tend to be most numerous when a new generation emerges, often in
response to rainfall. As many as 3000 adults of the smaller species have been
counted in some pads at these times. They feed on the dung flUids, and mutual
interference prevents any burial activity. On those occasions the pads are shredded
and deSiccated until only dry loose chaff remains; this quickly weathers away.
When tunnelling beetles are in breeding condition and are not overcrowded,
their digging activities result in excavated soil being pushed to the surface to form
small heaps or soil casts underneath and at the edge of the pad. The dung is taken
down the tunnels from the underSide of the pad, often leaving the crust intact. Such
a pad may appear untouched although it is hollow or filled with soil, and also
weathers away quickly. In contrast, the one ball rolling species currently
established in NSW cuts off lumps of dung from the edge or top of the pad, moulds
them into balls which are rolled away and fixed to the bases of the stems of
surrounding vegetation. The weight of a dung ball can be several times that of the
beetle. In this species the immatures develop above ground, and there is no dung
burial.
2
Birds often prey on dung beetles, as do foxes. Occasionally all the dung pads in a
region will be fragmented by the predators in their search for these tasty morsels.
However, dung beetles have evolved an ability to crawl down into their tunnels very
rapidly when the dung pad is disturbed, and this way many escape from being
caught.
Dung beetles often have mites on them. The mites are carnivorous, feeding on
small larvae and eggs in the dung pad. They also reproduce in dung. Dung beetles act
as "aeroplanes", carrying the mites from one dung pad to another.
--
-
adult breaks out
of dung ball and
digs its way to the
I soil surface
pupa
larva young adult \
fresh dung pat
I
~
egg
I soil casts
tunnel filled
tunnel often lined
with soil
with dung
brood mass
brood ball
containing )
containing
several eggs
one egg
-
-
'---
ball is attached to base of ball is cut
surrounding vegetation ball is rolled away out of dung pad
Figure 2. Life cycle of the dung beetle.
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