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AUSTRALIAN NATIVE MAMMAL CARE
Assignment
COMMON WOMBAT
Vombatus Ursinus
Sandra Stewart: July 2003
1
COMMON WOMBAT
Vombatus ursinus
PHYLUM
SUBPHYLUM
CLASS
SUBCLASS
ORDER
SUPERFAMILY
FAMILY
GENUS
SPECIES
COMMON NAME
Chordata
Vertebrata
Mammalia
Marsupialia
Diprotodonta
Vombatoidea
Vombatidae
Vombatus
ursinus
Common Wombat
(1) Triggs page 14
1. Description
Introduction
The common wombat is a marsupial mammal, and one of the world's
largest grazers. It has a short, stout, strong body. A lone, nocturnal,
animal wombats are rarely seen during the day. Of all the marsupials
they are the most intelligent. Despite their size and stature they are
capable of great speed.
A juvenile common wombat (1) page 54
2
Body Shape and Size
Stocky
Barrel shaped
Ends in a small vestigial bare tail:
Visible in young
Covered by fur in adults
They have thickset, low-slung bodies. Their average size varies according
to its area of residence.
Length
Height at
Shoulder
Weight
Mainland
100cm
1 metre
25cm
26.35kg
Flinders Island
78cm
Tasmania
81cm
17.6 kg
19.5 kg
Shoulders
Powerful
Designed for burrowing
Pelvis
Wide
Can flatten themselves out when lying prone.
"They are able to flatten themselves out like dough under a
rolling pin and slip through cracks less than ten centimetres
high."
(2) Woodford page 7
A wombat skeleton (2)
3
Coat
Most uniformly coloured.
A grey-brown wombat from Bombala in NSW (3) Triggs plate 3
Great variation in fur colour:
Glossy Black to Creamy coloured.
An ash-white wombat from coastal southern Victoria. (3) Triggs plate 6
Black wombats may have white patches on their fur and
sometimes white nails.
Albino wombats have been seen.
Patchy appearance if wounded.
New hair grows over the wound in a different colour to the rest of
the coat.
Hair is a mix of several different colours, which blend. The mixture and
blend form the overall coat colour
4
This coat is a predominance of black hair, some with gold band
(3) Triggs Plate 5
Colour may also be influenced by the colour of the burrow soil. Wombats
who burrow in clay may have a red coat, in loam, more black.
This light grey Tasmanian wombat is stained by red clay
(3) Triggs Plate 4
Texture of Coat
Hair is very coarse.
6cm long on the flanks and shoulders.
Rump bristles 1-2cm long
"The long guard hairs are about 200 microns in diameter,
which is nearly twice the diameter of the coarsest human
hair."
(1) Triggs page 17
Skin
Thick
Particularly on back and rump
Layer of skin protecting the pelvis is 1 cm thick.
It protects the wombat from bites of dogs and dingoes.
If a wombat is chased into a burrow it wedges its back against the burrow roof
to block the burrow. They have been known to crush a dog's skull or suffocate it
by doing this.
5
Head
Large
Set squarely on a short, strong neck.
Skull broad with strong bones.
Strong, rigid brain case.
The skull is used to move large, heavy objects when making a burrow.
The skull bones are so strong that they are not damaged by this use.
"A stubborn rock or stone encountered while digging a
burrow, a newly fallen tree branch or a small sapling
encroaching on a favourite pathway, a tautly strung wire
fence - the wombat simply pushes at them with its broad,
strong head, and with the not inconsiderable weight and
stubborn nature, it usually succeeds in moving the objects
aside or lifting it out of the way."
(1) Triggs page 18
Wombat Skull Dorsal View (2)
Whiskers
Five sets:
1) A long set on the muzzle
Smaller sets
2) Above eyes
3) On cheeks
4) Under chin
5) Under throat
Eyes
Small
Dark Brown
Set towards the side of the head.
Helps to prevent injury whilst digging
Protection whilst walking through undergrowth
Fleshy eyelids
Few short lashes
Poor eyesight
6
Wombats spend most daylight hours underground and
move around at night. The other senses are more important
than sight.
Eyes set towards the side of the head
Small erect ears. Lewis (4)
Ears
Small
Erect
Pointed tips
Set sideways on the head.
Can rotate only slightly to the front and back. The wombat has to
turn its whole head to pin-point sound.
Efficient collectors of sound.
Nose
Large
Covered in thick, bare skin
Most prominent feature of face
Skin usually dry
Openings and nasal passages are large
Good sense of smell
Relies more on smell than hearing.
Lips
Fleshy and flexible, particularly the upper with a gap to help when
selecting grass.
" a wombat is able to pick the choicest green stems no matter
how close they are to the ground."
(2) Woodford pg 99
7
Note the large prominent nose, small brown eyes and claws
blunted from digging (5) Stewart
Teeth
Two lower incisors
Only mammal to have two incisors in its upper jaw
A large gap between the incisors and the rest of the teeth.
One pre-molar and four molars on each side of the jaw.
All teeth are rootless and continue to grow throughout the life of
the wombat. This is an adaptation to the high amount of silicon in
the native grasses and roots eaten by the wombat, which would
turn most teeth to powder.
"As I write this I have a wombat jaw on my desk beside my
computer. If I turn the jaw upside down the teeth tumble onto my
desk. Each tooth looks like a miniature blunt tusk about two and a
half centimetres long. "
(2) Woodford pg 98
When a joey is born its teeth are designed for leaf eating. While the
joey is still in the pouch through thegosis (teeth- sharpening) the
teeth of the joey are ground down until the crown is suitable for
grass eating. (2) Woodford pg 98, 99
`
Wombat Skull showing teeth (2)
8
Wombat Jaw (2)
Legs
Short
Equipped for carrying a heavy body.
Designed for digging.
Feet
The wombat is a 'plantigrader", or sole walking mammal. It walks with the
entire sole of its foot on the ground.
They mostly walk and rarely run, but are quick when they do.
They can maintain a speed of 40 kilometres per hour for over one hundred and
fifty metres. (1) Woodford pg 7
(6)
Front Feet
Broad
Five Toes
Long, strong claws blunted at the edge by digging.
Hind Feet
Longer and narrower than front feet
The four toes have long sickle-shaped claws
The inner or first toe is a clawless knob.
The bones of the second and third toe are fused together.
9
Soles (front and back)
Fleshy pads.
Tough, leathery skin.
When a joey first leaves the pouch they are pink and soft.
Pads become darker, leathery, toughened with age and wear.
Left: The Front Foot
Right: The Hind Foot (3) Triggs Figure 3.5 page 23
Sexual Characteristics
No obvious sexual characteristics.
Females may be, and are, often larger than males.
Male
Penis:
Stored within the body.
12-15 centimetres long when erect.
Retreats into the body in an S shaped curve.
Testes
Held in the scrotum on the lower part of the belly.
Female
Pouch
Backward opening
Almost hairless
Controlled by a sphincter muscle.
Sphincter muscle closes the pouch to keep it free from dirt whilst
digging, and in burrows.
Teats
Two teats
Situated at the back end of the inner pouch wall.
This question. (2) Triggs pages 12 -23
10
2. Distribution
Distribution of the Common Wombat in Australia
(7)
It is thought that wombats were quite widely spread at the time of
European settlement but records are few.
European settlers had been in the colony of New South Wales for ten
years before the first recorded sighting of a wombat.
The common wombat used to occupy:
Southeastern Queensland
Through New South Wales along the Great Dividing and
associated ranges
Most of Victoria (except the north-western corner)
Southeast of South Australia
Tasmania
Many larger Bass Strait Islands
11
The range of the common wombat has shrunk considerably in the last two
hundred years:
It has almost disappeared from the western part of Victoria.
Now only occurs on two of the Bass Strait Islands:
Flinders Island and one other
Has disappeared from much of New South Wales where it
formerly ranged
Numbers have also declined in South Australia
(1) Triggs page 11
Detailed Map of the Range of the Common Wombat
(3) Triggs page 11
12
3.Care in Captivity
Introduction
A wombat needs specialised care in captivity. Feeding, housing and handling
must reflect the needs of the wombat in terms of its stage of development. These
needs will change, particularly in reference to diet and housing as the animal
grows.
At all times the physical and mental health of the animal must be the primary
concern.
On the following pages there is a chart which shows the age, growth and
development of a wombat combined with its Housing, Feeding, Toileting,
Handling and Restraint needs for each age group.
More detailed information on needs is given at the end of the chart.
Exploring the rehabilitation yard. (8) Moloney
13
Approximate
Age
Weight
Birth
0.5gms
1 month
Feed
Housing
Toileting
and faeces
Restraint and
Handling
Not
Applicable
Not Applicable
Kinder to
euthanase
Not
Applicable
Not Applicable
Kinder to
State of Development
5gms
Hairless; mouth, front
limbs and shoulders well
developed; eyes and most
other organs embryonic;
sharp curved claws on
front feet but hind limbs
undeveloped; lips joined at
side. Nil survival if
orphaned
Permanently attached to
teat; ears fused with the
skin of the head; hind legs
developed; outer edges of
the lips joined; hairless. Nil
survival if orphaned
14
euthanase
Approximate
Age
3 months
3.5 months
Weight
Feeds
Housing
Toileting and
Faeces
Handling and
Restraint
100-110gms Facial structures forming;
ears fully unfolded but
lying close to head;
whiskers forming but
otherwise still hairless; lips
still joined.
Slim chance of survival if
orphaned
Feed every 2-3
hours
8-12 feeds daily
will only take a
small amount
Wombaroo MTM
teat
Feed on heat
source
Artificial heat source
30-32oC
Inner and outer pouch
plus sheepskin
If feet bright pink the
joey is too hot.
Carer
stimulates
joeys cloaca
to toilet
Faeces
almost liquid
Yellow in
colour
Handle
gently, as
little as
possible.
Only to feed,
toilet and
moisturise.
Fine fur forming on ears;
eyes may be open; still
attached to teat
Feed every 3-4
hours
6-8 times daily
Wombaroo MTM
teat
Feed on heat
source
Artificial heat source
House at
29-31oC
plus sheepskin
joey is too hot
Carer to
stimulate to
toilet
Faeces
almost liquid.
Yellow in
colour
Handle
gently, as
little as
possible.
Only to feed,
toilet and
moisturise
230-250
gms
15
Approximate
Age
Weight
Development
Feeds
Housing
Toileting and
Faeces
Handling and
Restraint
4 months
380-400gm
Eyes open; lips beginning
to separate
Feed every 4 hours
6 times daily
Feed on heat
source
Wombaroo MTM
teat
House at
28-30oC
plus sheepskin
joey is too hot
5 months
750-800gms
Fine layer of fur on dorsal
side of limbs; no longer
attached to teat; lips fully
separated; lower incisors
erupting.
Feed every 4 hours
during the day. No
middle of the night
feed.
5 times daily
Wombaroo MFM
or LF teat
May still need artificial
heat source.
House at 28oC NO
higher
Small Escape proof
basket
Observe feet
Carer to
stimulate to
toilet
Faeces
custard to
toothpaste
Yellow
Carer
stimulates to
toilet
Faeces
custard to
toothpaste
Handle
gently, as
little as
possible.
Only to feed,
toilet and
moisturise
May be taken
out of pouch
for short
periods.
Basket needs
to be escape
proof
16
Approximate
Age
Weight
Development
6 months
1-1.4kg
Fine fur about 1mm long over
much of the body; skin of nose
and soles of feet still pink; first
molar visible; upper incisors
erupting; head out of pouch
occasionally.
Feed as for five
months
Give access to dirt
to eat to aid in
establishing gut
flora.
House at <28oC
Inner and outer
pouch.
Basket needs to be
escape proof. Try to
pair up with a
similar aged and
sized wombat
7 months
2.2-2.5kg
Fur thicker; premolars and
second molars erupt; ventures
out of pouch with carer
Feed every 6 hours
Offer solids
House at < 28oC
Offer water in a
bottle
Offer dryish
grasses with roots
and dirt attached,
to further
establish gut flora
Should suck on
dirt and
experiment with
grass.
Place pouch in a
solid wooden box
with smooth sides to
prevent escape.
Better to have no
view to the outside.
Have Kitty Litter
available in box.
Feeds
Housing
17
Toileting and
Faeces
Restraint and
Handling
May be taken
Carer
out of pouch
stimulates
and basket
cloaca to
for games
toilet
with carer.
Faeces
Toothpaste
Will start to
defaecate
outside
pouch. Can
be trained to
use kitty
litter
Enjoys
Carer may
playing and
stimulate or
rumbling
joey may
toilet on their with carer. If
there are two
own.
together they
Toothpaste
will be happy
to Pellets
playing with
Place on the
each other.
ground
If alone has
outside
bonded to
morning and
carer and
night
demands
Kitty Litter
much
in box.
attention
Approximate
Age
Weight
Development
Food
Housing
Toileting and
Faeces
Handling and
Restraint
8 months
2.7-3.4 kg
Fully furred but tail still
visible; muzzle still narrow
and ears appear too large for
head; out of pouch more often;
nibbling grass while in pouch
with head out
Feed every 6-8
hours
Eating solids
Green grass may
be offered when
pelleting,
introduce slowly.
Provide a constant
supply of food.
Provide water in a
spill-proof bowl
House at <28oC
Toothpaste
to Pellets
Place on the
ground
outside
morning and
night to
defaecate
Have Kitty
Litter
available
Ensure the
box is escape
proof or the
wombat will
come looking
for 'mum'.
Pick up with
one hand
under
forearms or
around girth.
Place wooden box
outside. Still have
the pouch available
Should have a
'friend'
Provide some straw
for experimental
'burrowing'
18
Approximate
Age
Weight
Development
Food
Housing
3.6 - 5.2 kg
Leaves pouch permanently,
soles of feet darkening, also
skin on nose; Eats more grass
Feed 3 times daily
Eating solids
Provide a constant
supply of food.
Provide water in a
spill-proof bowl
Green grass may
be offered.
When over 6kg if
a large adequately
fenced grazing
area can be found
allow to graze
freely at dusk and
dawn whilst being
observed.
Remove pouch but
leave an item that
has the joey's smell.
Outside night and
day in a secure
wooden box.
Needs to be in a cool
area.
Preferred
temperature 25oC
but will tolerate up
to 28oC.
9 months
5-6.4kg
10 months
Fill the box with
straw to enable
burrowing
experience
to develop.
By 10 months joey
should be in an
outside enclosure.
(see 12-15 months)
19
Toileting and Handling and
faeces
Restraint
Will choose
own spot to
deposit
Squarish
Pellets
Try to handle
less and less.
May still be
picked up as
for 8 months.
Approximate
Age
Weight
Development
Food
Housing
Toileting and
Faeces
Handling and
Restraint
12 months
7.3-11.3 kg
Weaned during this period
Feed twice daily
Outside in an
enclosure with climb
proof walls.
Will choose
own spots to
deposit
Squarish
Pellets
Withdraw
contact
except to
check food
and water
Orientation
walks should
be taken if it
is to be a
'soft' release
Cease walks
by 15 months
or around
11kg.
Have as little
contact as
possible. If it
can be
arranged get
a stranger to
supply food
and water
15 months
Wean
Have a constant
Provide a burrow.
supply of native
Place something
grasses common to
the release area if with a familiar smell
in burrow initially,
possible.
particularly if alone.
20
Approximate
Age
Weight
Development
food
Housing
Toileting and
Faeces
Restraint and
Handling
18 months
16.8-24kg
Independent
Will be sexually mature by
approximately two years of
age.
Release
If soft releasing
provide an exit
point from the
enclosure to allow
the wombat to come
and go from its
familiar burrow.
Will choose
own spot to
pellet,
initially
hiding them.
As the
wombat
becomes
sexually
mature it will
start to
display scats
on rocks and
logs.
To catch.
Try to
contain in
pen, Throw a
large blanket
over the
wombat and
tackle.
Beware of
teeth and
claws.
Two people
will be
needed to
restrain.
Chemical
restraint will
be required if
transporting
for a longer
period.
If hard releasing,
place wombats own
scats in a burrow
which has not had
recent occupation.
If remaining in
captivity provided
the enclosure is big
enough, secure and
cool it should not
need to be moved.
(1) Triggs pages 136-137 (3) Lardner-Smith (4) George et al pages 1
21
Holly's Story So Far ...
Holly was found in her dead mother's pouch on Sunday December 8, 2002. A licensed wildlife carer was called to pick her up.
She made several phone calls to more experienced wombat carers to see if she should be given a chance or not. Everything was
there, everything was perfect, just in miniature. It was one of those days when the only response was answering machines. The
one person she reached said to "Not even go there." The carer placed the tube from a child's giving set, filled with milk, gently
into her mouth. She started to suck and her tiny tummy was full. She was toileted and this end worked too. She was too alive to
euthanase.
One of the calls was returned and advise was given to contact Robin Moloney at Berkley Vale on the Central Coast because she
creates miracles with pinkies. Contact was made and Robin agreed to meet at Cessnock within two hours. These are the only
pictures she could find of Holly's progress. At the end of June 2003 she is nearly 4 kilograms and preparing to be rehabilitated at
"Rocky Creek", within her gene pool.
Holly February 15th 2003, 69 days, (about 10 weeks) after her rescue.
Holly 20.4.03, 133 days (19 weeks) in care. (8) Moloney
22
4. A Description of its Lifestyle in the Wild
Burrows
The common wombat is a nocturnal mammal who spends two thirds of its
day in a burrow, particularly during daylight hours. The burrow is
essential to its survival. There are major, medium and minor wombat
burrows.
A wombat burrow in the side of a dam that holds no water.
(5) Stewart
Table of Burrow Type and Characteristics
Burrow Characteristic
Major Medium Minor
Burrow Burrow Burrow
Used by generations of wombats
Yes
No
No
Large mound of dirt from 2.5sq metres up
to 8sq metres formed from years of
excavations and renovations.
Yes
No
No
Smaller conspicuous mound
No
Yes
No
Small overgrown mound often the only
thing remaining.
No
No
Yes
Entrance large enough for a human to get
through. Well worn and smooth
Yes
No
No
Single entrance .5metres high and almost
.5 metres wide. Oval or inverted U shape
Yes
Yes
No
Small entrance. Too small for a bulky
adult or wombat to enter.
No
No
Yes
Yes
No
Yes
'sit' - flattened vegetation or a small
excavation near a burrow entrance used in
daytime cooler weather or to sniff the area
before starting to feed
23
Dug on sloping and steeper slopes. Less
chance of run-off flooding.
Burrow on flat or weakly sloping ground.
Descending steeply at first for a distance
of 0.5metres to 5 metres from the
entrance.
Tunnels in straight line or change
direction. Slopes up and down.
Sleeping chamber made in hollows of
down slopes. May be lined or unlined with
vegetation
No faeces in burrow
Forks into two or more tunnels which link
up and form a network of interconnecting
burrows. Tunnels may be 10-18 metres
long, or even longer. Connected burrows
form over long periods where there is
limited good digging ground.
Yes
Yes
No
some
some
many
Yes
Yes
No
At least
1-2
At least
1-2
Maybe
1
Yes
Yes
Yes
Yes
No
No
Suitable digging ground. Wombat
burrows are spaced so that little
interconnection occurs.
Yes
Yes
Yes
A commenced burrow in an unsuitable
sight. Usually abandoned after 1-2 metres.
Usually only used as a temporary shelter
or in an emergency. May become
overgrown or taken over by rabbits.
No
No
Yes
No
No
Yes
Small abandoned burrow in good sight.
May later be excavated by another
wombat and extended to a medium or
even major burrow.
This mound hows a burrow excavated in rocky
ground. (1) page 60
24
Diagram of a Common Wombat Burrow Network.
(1) page 61
1. Several entrances often large enough for people.
2. Entrances may be supported by tree roots.
3. Mounds of excavated soil near entrance.
4. Females with young or about to give birth may have a separate nursery
burrow.
5. Sleeping chamber at the end of a tunnel.
6. Resting vestibule to judge outside temperature and light before
emerging.
7. The wombat usually follows a well-worn path.
8. Sit for basking in cooler months or assessing before moving off to
graze.
9. Wombats will not stay in a hole with a snake.
10.& 11 Foxes may move in looking for rabbits who have taken up
residence.
12. Bush rats may use wombat burrows.
13 & 14 Tunnel extensions may link up with other entrance
(3) April- June 1993 pg 61
25
Siting a Burrow
sloping sides of hills
forested slopes above gullies and creeks
dig where the earth has been exposed eg under fallen trees or
rocky outcrops.
exploit weaknesses where excavation is easier.
Wombats will commence burrows almost anywhere but may stop
them after 1-2 metres if unsuitable.
Many burrows 15 metres or more are the work of more than one
wombat.
Digging a burrow
An adult wombat has no need to dig a new burrow, but may
extend and renovate existing burrows.
A young newly independent wombat is more likely to start a
burrow from scratch.
It explores a few scratches with its front paws and can decide if the
area is suitable, if so, serious burrowing commences:
Back legs braced the wombat digs with one front paw for a
few moments and then the other.
Spade like claws loosen the soil, broad palms scooping it up,
thrusting it out sideways and backwards.
Any encroaching grass or vegetation is bitten off and eaten
or cast aside. Roots are either bitten off or pulled free.
Lumps of rocks, hard clay or soil may be bitten to free them
from the soil.
The back legs kick and push the soil backwards. This
continues with the wombat taking a break about every 20
minutes.
If need be the wombat will lie on its side and excavate the
walls and sides of the tunnel.
Depending upon conditions wombats can dig between 1-2
metres a night.
A wombat intent on digging a burrow (1) page 60
26
Burrow Occupancy
Burrows are not exclusively used by one wombat.
Several different wombats may use a major burrow but usually at
different times.
Other animals that use wombat burrows include:
rabbits
Dusky Antechinus
Brown Antechinus
Bush Rats
Foxes
Wild dogs
Snakes
Foxes and wild dogs are not tolerated. A wombat will not enter a
burrow which houses a snake.
The burrow offers:
security
easy defence against predators
protection from bushfires and other hazards
a cool, comfortable environment for a day's rest.
27
A Common Wombat's Day - Life in the Burrow
Time of Day
Place
Activity
Early Morning
Usually before dawn
Nearly always before
sunrise
Approaches the
burrow where it
will spend the
day
. It's body temperature has increased
by 3oC whilst outside the burrow.
A few metres
from the
entrance
It rubs its flanks against the bark of a
tree, scratches once or twice and
shakes itself if wet.
(3) Triggs Figure 5.1 page 37
Moves into
entrance tunnel
May leave a few drops of fluid as a
scent trail
Scratches around, clears an area. Sits
Chooses a
sleeping chamber on rump, head down, eyes half shut.
Head drops until it falls on its side.
deep in the
tunnel
The body temperature falls slowly to
34.7oC to reduce the amount of
energy used to regulate temperature.
28
After an Hour
Sleeping
Chamber
Burrow
temperature
never exceeds
25oC
Changes Position.
May roll right over to the other side
or onto its back.
This position is both relaxed and
vulnerable. It shows how secure the
burrow is.
(3) Triggs Fig 5.3 page 39
The breathing rate slows from a rapid
30 times a minute to 14 times a
minute.
Whilst Sleeping
Sleeping
Chamber
Changes positions, grinds teeth,
snores, yawns, sighs, scratches, snorts
and rumbles from various body parts.
Late Afternoon
`
Lies prone.
Moves slowly
along tunnel to
within 1 metre of
the entrance
It assesses the air temperature as its
ability to regulate its body temperature
decreases as the temperature rises above
25oC. Temperatures above 35oC cause
distress.
29
Life Above Ground
There is great diversity in the amount of time spent above ground. This is
influenced by:
weather
habitat
season
proximity of other wombats
proximity of enemies eg feral dogs, foxes, humans
Conditions and Time for Emerging from Burrow:
Conditions
Emerges from burrow
Usually
After sunset
Good weather
About dusk
Hot Days >28oC
wait until after midnight
Winter
Food scarce
Leave as early as 3-4pm on overcast
days , after heavy rain or snow.
Suffering from mange
In daytime
Regions where conditions are ideal eg
Tasmania
Many hours in the daytime
A wombat pauses at the burrow entrance to sniff the air before
leaving (3) page57
30
Table of Wombat Above Ground Activities:
Time
After Sunset
Soon after leaving
burrow
Up to an hour later
Where
Activity
Burrow Entrance
Pauses to assess
environment
Burrow
Moves out of
entrance
Mound
Dozing
Sampling the air
Near burrow
Immature animal, 2
years old
Deposits scats in a
patch of ferns or
undergrowth
Mature animal
Deposits scats on a
rock, stone or sticks
or some raised
elevation. Backs up
to the elevation, male
will make 2-3 long
scratches with first
one paw then
another.
Female chooses
elevated position but
only scores ground if
angry.
Vicinity of burrow
Feeds on favoured
grasses
Moves into range.
Travelling well-worn
paths
Not far from burrow
or moves
May scratch or use
rubbing post to rub
back, flanks or other
body parts whilst
considering scents.
Early part of the
night
A considerable
distance from
burrow,
Grazes occasionally
until a suitable
grazing area found.
Then grazes
constantly for some
time. Lifting head
periodically to sniff
and listen.
31
After an hour or
two of eating
In range
After 3-4 hours
A burrow
About another
hour or so
Emerges in range
Before sunrise
Approaching the
burrow
Enters to sleep for
A different burrow
to the day before and the day.
even the night
Early morning
before dawn
Eats sporadically,
sits down, roams
further between
grazing bouts.
sleeps, excavates,
extend
continues feeding
(this pattern may be
repeated several
times with the same
or different burrows.
Deposits scats
The wombat returns to its burrow
(3) Triggs Figure 6.20 Page 69
32
Food
A wombat can live on poor quality grasses.
There is no better converter of grass to meat
Their digestive system is three times more effective than kangaroos
(2) Woodford pg 125
Wombat Digestion
Before discussing feeding it is necessary to discuss the digestion of the wombat. A
wombat is a hind-gut fermenter.
The wombat must chew its food well. It has a very small stomach. Lipids,
proteins and soluble carbohydrates in plant cells are digested and absorbed in
the stomach and small intestine (which is about 3 metres long in an adult.) The
colon (large intestine) is about 4 metres long and has about 68% of the capacity
of the stomach and intestines and contains a dense population of bacteria. The
gut capacity is one third greater than herbivores of a similar size. This allows
slow fermentation of fibres, this fermentation is the second step in digestion
(2) Woodford pg 125
Bacteria in the colon is 3-6 times larger than in the stomach and small intestine.
The food is broken down as it passes through the gut, by the bacteria, in the
process of microbial fermentation. This process allows all energy to be extracted.
It can take 49 hours for food to pass through a wombat's gut.
How they eat
Jaws work constantly as the head moves over the tussock or tuft of grass.
It arranges these in the mouth
It jerks its head slightly up. down and sideways so the leaves are broken or
pulled cleanly from the axils or bases.
Sword grasses on the side of the mouth
Grasses
Wombats prefer coarse, high-fibre grasses.
Mostly grasses are monocotyledons having one seed leaf and long parallel veins.
Forest area
Tussock grass
Open pastoral
Kangaroo grass
Wallaby grass
Coastal forest
wide variety
Fine Tussock Grass
Spear Grass
Fine Tussock grass
Kangaroo grass
33
Also
weeping grass
Reed Bent Grass
New tips of Forest Wire Grass in spring
Coastal Wombats
Sedges
Rushes
Club Rushes
Mat-rushes
Introduced Grasses
Paspalum
Parramatta Grass
The grass chosen depends upon what is available which varies with conditions,
seasons and areas.
Scats
Wombat scats displayed on a stick.
Most likely from a wombat over 2 years old.
(5) Stewart
Cube-shaped pellets
Four to eight at a time
Usually contain fragments of several monocotyledon plants
May also contain fragments of seed coat or leaf cuticle
These smaller scats from a
younger wombat were
partially hidden by grass,
possibly indicating a wombat
not yet sexually mature.
(5)Stewart
34
Reproduction
At about two years of age wombats start to display their scats
prominently rather than hiding them as they do when they are younger.
This establishes a home range and indicates that sexual maturity is near.
Reproduction is dependant on the cycle of the female.
Female
When approaching first heat or oestrous cycle a young female
displays her scats.
The pheromones let any males know that she is approaching
oestrous.
If her range has a small population she may leave her scats beyond
this area.
May be sexually active at any time of the year but studies have
suggested that there are seasonal peaks which differ according to
the areas.
Polyoestrous, having a series of oestrous cycles.
Each cycle about 33 days.
Oestrous Cycle in Wombats
1) Pre-oestrous
Four to five days before oestrous
Aggressive
Active
2) Oestrus
Ovulation occurs
Fifteen hours
Urogenital opening becomes moist and swollen.
3) Post-oestrus
Four weeks
(If she becomes pregnant her cycle ceases and probably
won't start again until after the joey is weaned).
This could be twenty months or more:
a) One month gestation
b) Eight to ten months in the pouch
c) Eleven months at heel
Males
If an area has a cluster of burrows males may fight for females.
Only active role is to mate.
No bond formed.
Play no role in rearing young
35
Courtship
Male chases female.
Female trots in a circle and figures of eight.
Slows down every so often to let the male catch up.
(2) Triggs Figure 7.24a page 95
After about two minutes chasing the male gives a powerful bite to her
rump.
(2) Triggs Figure 7.24b page 95
Female stops running.
(3) Triggs Figure 7.24c page 95
Male grips her hindquarters with his forelimbs, rolls her to her side and
mounts her
Female in prone position during copulation.
36
(2) Triggs Figure 7.24d page 95
After a few minutes the female gets up and the process is repeated.
This can be repeated seven times in about twenty-five minutes.
Mating of wombats in the wild has only been seen twice and visually
recorded once.
"the repetitive nature of the courtship and mating behaviour
observed by Taylor and Marks seems to suggest that it is
typical."
(2) Triggs pg 94
Video (1) Wombats:Bulldozers of the Bush
Gestation
About 30 days
Preparation
Mother cleans pouch.
Probably sits on rump:
Hind legs extended forward
Cloaca extended slightly upward
This pouch cleaning position is also thought to be the position used for
birth (2) Triggs Figure 7.1 page 71
37
Birth
Newborn undeveloped and small
Size of a small bean.
Emerges head first from the birth canal.
Forelimbs are well developed. The young grasps the mother's fur and uses
the front legs alternately and swinging the head side to side travels the 10
centimetres from the birth canal to the pouch.
The mother cannot help as the baby is too delicate and would be injured
or killed by her.
The joey is in the pouch by one to two minutes after birth.
It attaches itself to the teat.
"the newborn's mouth is joined at the outer edges so that its
mouth is a small open circle. When the small swelling at the
tip of the nipple is sucked in, it expands inside the mouth so
that the young becomes firmly attached to it - so firmly that
any attempt to pull it off will tear the skin around the mouth
and make it bleed." (2) Triggs pages 71-72
The Pouch
Constantly warm
Humid
The joey
Relies on mother's warmth and humidity from pouch
Can't control own body temperature until about seven or eight months
old.
Is permanently attached to the teat.
38
Growth and Development Table
Approximate Weight
Age
Range
At birth
0.5gms
Length
15mm
Hairless.
Mouth, front limbs and
shoulders well developed.
Eyes embryonic
Most other organs
embryonic
Sharp, curved claws on
front feet
Hind limbs undeveloped
Lips joined at outer edges.
Length
7 cm
Permanently attached to
teat
Ears still fused with the
skin of the head.
Hind legs developing
Outer edges of lips still
joined together
Hairless
At Birth Triggs page 138
Approximate Weight
Age
Range
One Month
5gms
One Month (3)Triggs page 138
One Month (3)Triggs page 72
Figure7.2
39
Edward 50 grams. Approximately six to eight weeks old. (8) Moloney
Approximate Weight
Age
Range
Three
100-110gms
months
Length
14 cm
Facial structures forming
Ears fully unfolded, lying
close to head
whiskers forming
but otherwise still hairless
Lips still joined.
Three Months (3) Triggs page 138
40
Edward 150 grams. Approximately
ninety days or three months old (8) Moloney
Approximate Weight
Age
230-250gms
Three and
one half
Months
Approximate State of Development
Length
16cm
Fine fur forming on ears;
eyes may be open; still
permanently attached to
teat
Edward 268 grams Approximately Three and one half months old.
Note the vestigial bare tail and fine layer of fur.
(8) Moloney
41
Four Months 380-400gms
17 cm
5 months
18cm
750-800gms
Eyes open;
lips beginning to separate
Fine layer of fur on dorsal
side of limbs;
no longer permanently
attached to teat;
lips fully separated;
lower incisors erupting
Five Months (3) Triggs page 138
Five Months
The pouch expands as the joey grows.
By the time fine fur is developing the pouch has expanded twelve
centimetres in any or all directions from the mid-point of opening.
Usually expands more to the mother's chest than any other direction.
Approximate Weight
Age
Range
1-1.4kg
Six months
Seven
months
2.2-2.5kg
Length
19.5- 20.8
cm
Fine fur about 1
millimetre long over much
of the body;
Skin of nose and soles of
feet still pink;
first molars visible;
upper incisors erupting;
head out of pouch
occasionally
23-24cm
Fur thicker;
premolars and second
molars erupt;
venture out of pouch
when in burrow
42
Six to Seven Months (3) Triggs page 138
Explores the burrow always touching mum.
Pushes head into pouch to suckle
Teat
Up to ten centimetres long.
Pencil thin
Can protrude from pouch opening
Starts to play with mum:
bites
chews fur
pounces on paws
As soon as mum starts to leave burrow, joey scrambles back into the
pouch
Eight
Months
2.7-3.4kg
23-25cm
Fully furred but
rudimentary tail still
visible; muzzle still
narrow and ears appear
too large for head;
out of pouch more often;
nibbling grass while in
pouch with head out, as
well as when out beside
mother
More confident out of pouch.
Moves short distance from sleeping mother
Digging practise - scraping at burrow walls.
43
Nine months
Ten months
3.6-5.2kg
5-6.4kg
25-28 cm
28cm+
Leaves pouch
permanently;
soles of feet darkening,
also skin of nose;
suckles from elongated
teat;
stays close to mother most
of the time;
eats more and more grass
probably eats mother's
scats occasionally to
establish bacterial
cultures in its digestive
system.
Nine to Ten Months (3) Triggs page 139
Very little is known about this time.
Joey is vulnerable to predator's particularly feral dogs and dingoes.
At mother's heels outside burrow.
Much time spent in or near burrow.
May race back to burrow without mother if frightened.
Calls mother if it wanders too far away.
A higher pitched call if frightened or in danger.
Deposits scats secretly in undergrowth.
The mother may leave it alone in a burrow for a night as part of weaning.
44
Approximate
Age
12 months
15 months
Weight
Range
7.3-11.3kg
12-19kg
Length
Range
Weaned during this
period;
remains with mother for a
variable time after
weaning.
Ten to Twelve Months
`
Becomes more confident
Grows quickly
More familiar with area
Playful
Playtime
1) Stands still, front legs stiff and straight
2) Jerks head and shoulders up, may jump
3) In any order
tosses head from side to side
jumps in the air with all four legs off the ground
rolls over on its side
races off at a gallop
comes to a sudden stop
reverses 180 degrees on the spot
races back to its mother
just stopping or diverting before collision
lies flat on its stomach
swings head from side to side, lips drawn back in a 'grin'
Digging practice
45
A Hand raised wombat will still like to stay
close to 'mum' at this stage. as a wild baby needs to stay near its
natural mum. Millie. (6) Stewart
18 months
16.8-24kg
Usually independent
Eighteen Months (3) Triggs page 139
This is a time that not much is known about. When independent of their
mother the young wombat has to:
find a vacant burrow
share a burrow
or
dig one of its own
Females may have more chance than males of living in the mother's home
range.
Males may either be driven out or move themselves to inferior areas and
live in vacant burrows or share home ranges of other wombats until
enough status is achieved to establish a home range in a better area when
a former resident vacates it through death.
By two years of age the wombat may weigh about 22 kilograms and be
ready to become sexually active.
This question (1) Triggs pages 138-139, 24-97
46
Care In Captivity: Detailed Descriptions
Unfurred Joeys And Those Needing Artificial Heat
Housing:
A soft cotton liner bag
eg pillow case, old sheet sewn into an appropriate
size.
Woollen outer pouch
Place both in a bag made of old sheepskin with the fleece to the
outside and the inner bag folded right over the top to stop chewing
of the fleece.
Synthetics should not be used; they are either too hot or too cold.
They can also rub and cause pressure sores.
If chewed synthetics do not pass as easily through the digestive
system as natural fibres.
Synthetics may crystallise in the digestive track over time.
Enclosure
Confine the joey in a suitably sized basket or box so that it
cannot move too far from the heat source and get cold.
Heating
Furless
< 600 grams 30oC to 32oC. No higher
Developing Fur
> 600 grams 28oC No higher
If the feet are bright pink the joey is too hot.
Suitable heating devices
Heating Pad
Water Bed
Pet Warming Pads
Electric blanket under a wine cask bladder partially
filled with water, this forms a waterbed.
(9) George et al page 15
47
Monitoring Temperature
A constant temperature is important and should be
monitored carefully.
Over or under heating can cause stress, long-term
problems and even death.
Digital thermometers with probes can be used.
The temperature taken is the air surrounding the
joey. Not the joey's temperature or the heat source
temperature.
How to use a temperature probe correctly
(9) George et al page16
Unfurred through to 6-7 months old
Feeding
Wombats are lactose intolerant and must not under any circumstances be fed
cows milk.
There are several choices available, Divetelact and Wombaroo being the most
commonly used.
Wombaroo is designed for a species and attempts to mimic the quality of the
mother's milk at the same growth stage.
Divetelact is a universal formula for a variety of species and growth stages.
Both formulas have been used successfully but directions for use and volumes to
feed must be adhered to.
48
The teat used must be of an appropriate size. The hole must be very small for an
unfurred wombat.
Wombaroo MTM teat for joeys up to 5.5 months of age. (top)
MFM and LD teat for a joey 4 months to 7.5 months. (middle)
FM teat for 7.5 months and over (9) George et al page 22
"It is important to feed a joey in an upright position or lying on its
side. Never feed a young wombat lying on its back as milk may be inhaled or
catch behind the soft palate. Joeys tend to lie on their sides to feed from 600
grams onwards. Sometimes mother wombats lie on their backs and the joey
then lies on its stomach to suck."
Sterilisation
It is vitally important that all feeding and preparation utensils are sterile.
Wombats of this size have had little chance to build up immunity from their
mothers and may get infections easily, which with a poor immune system could
mean death.
Hands must be washed before feeding and in-between feeds if there is more than
one joey.
All bottles and teats should be rinsed thoroughly in cold water, immediately after
use, this prevents protein setting.
Hot wash in warm soapy water with a bottle brush as soon as possible.
Rinse clean.
Bottles and teats should be sterilised in a commercial anti-bacterial solution for
12 hours.
Rinse in boiling water to inactivate the bleach.
(5) Keen page 56
49
Toileting
Stimulating the joeys cloaca (unlike in other marsupials) may have little result.
Some wombats may respond to firm but gentle pressure between the cloaca and
the tail. At this age joeys should pass faeces several times a day. The faeces may
just stain the inner liner. It is important that this is replaced as soon as it
becomes soiled.
7-8 months
Heating
Supply a heat source so that the joey can use it if necessary.
Young joeys need to be well insulated in cold weather; a sheepskin makes
a good extra layer.
Watch closely for heat stress, even a heated house in winter can cause the
joey problems
On hot days place the joey in the coolest place available
The bathroom tiles are cool.
Supply wet towels to sleep on if needed.
Millie, summer of 2003. The bathroom supplied the coolest spot. This was
where she spent most of her days. (6) Stewart
50
Enclosure
Larger than previously used
A wooden box with smooth sides to prevent climbing out.
If the wombat can't see out it is more like a burrow.
The joey can leave the pouch, if it wishes, in a safe environment
Have the pouch in a cool, dark place.
A wombat box with room, for two, to play. Grass is supplied for
eating, a log for playing and pouches are readily available if
needed. (8) Moloney
Food
Dirt and native grasses should now be a well-established part of the diet. The
joeys should be nibbling and experimenting with the grasses this aids in the
establishment of gut flora.
Sterilisation
Good hygiene is still necessary in terms of bottles and teats. Food dishes must be
washed daily and food remains removed.
Toileting
By placing the joey outside on the grass twice daily, defaecating in its box may be
avoided. If the joey defaecates in the box or in the kitty litter this must be
cleaned up as soon as possible.
51
9 months - Emerging
Housing
During this time the joey's box needs to be placed outside and the pouches
removed. The box should be filled with straw to give first burrowing experiences.
This prepares the joey for life in an outside enclosure with a burrow. A lid (with
ventilation) should be placed on the box to prevent the joey escaping and trying
to find the foster mum. One with a perspex viewing area allows the wombats to
be observed without being disturbed. Less human attention is needed,
particularly if there are two wombats.
Food
The joey should be introduced to dry native grasses. Other suitable foods are
Kangaroo pellets, steamed rolled oats, meadow hay or poor quality lucerne hay.
It is best though to provide a diet of native grasses as this is what they will
actively seek in the wild. Grasses need to be anchored as the instinct for the joey
is graze on grasses that are growing in the ground.
Note the big colour differences in these young wombats in their
outside box (8) Moloney
52
10 months - 5 kgs and over
Transfer to an outside yard
This needs to be carefully planned to be escape proof. A wombat wanting
to return to its foster mum will find any weak spot in an enclosure.
Wombats can:
climb over
dig under
chew through
a variety of materials.
Sides need to be smooth. Corrugated iron with the vertical profile, or
a large out of ground swimming pool wall are suitable. The wall needs to
be firmly attached to the ground.
Wombats climb well.
If wire is used they may tear their claws from their feet on the wire
whilst climbing.
They have been known to climb chicken wire to 4 metres.
This wombat yard has been made from a combination of a
pool wall and vertical profile corrugated iron. There is mesh
covered in dirt extending from 1 metre inside the pen to 1 metre
outside the pen. This is to help prevent the wombat digging out
and predators digging in. (5) Stewart
53
Sides need to be dug into the ground for 1 metre.
OR
Reinforcing mesh needs to be placed horizontally over the entire floor
space or at least for one metre on either side of the wall. This helps to
prevent the wombat digging out near the walls and predators from
digging in.
Cover the mesh with dirt.
Millie showing the scars acquired whilst
successfully seeking out the weaknesses
in the above yard. This fur will grow back a different
colour. (5) Stewart
Wombats should not be housed on concrete as footpads can become worn
and infected.
The yard needs to have drainage, logs and rocks for scratching and trees
for shade.
54
This yard has trees for shelter, as well as rocks and logs for exploring.
Her former box was placed in the enclosure to provide extra shelter,
because it was familiar and had her scent on it.
(5) Stewart
This view shows how the enclosure is built naturally into rock. Additional
shelter is provided by the corrugated iron jutting out from the rock. The
fencing on the top of the rock is to prevent predators jumping in.
(5) Stewart
55
Burrow
Provide a place where a long burrow with a chamber at the end can be
dug. If a slope is chosen the wombat may dig into the slope.
An interim burrow may be a concrete pipe or large plastic drum well
insulated with straw bales. Or a covering of concrete with the hole
already commenced.
Don't put these near the perimeter and ensure that they cannot be moved,
as the wombat will use it as a ladder to escape.
This burrow with a concrete covering has only been started.
It is up to the wombat to complete it. (9) Russell's Burrow
An already prepared burrow may be made.
This burrow has an entrance tunnel and a chamber
with 'mum's' T-shirt to provide comfort. (5) Stewart
56
The hole is covered with corrugated
iron supported on cross beams of wood.
It is then covered with dirt for insulation. (5) Stewart
The completed hole, which was entered reluctantly
at first, but she now uses constantly. (5) Stewart
57
12-18 months
Prepare for Release
Up until three months before release if the wombat is to be 'soft' released
orientation walks around its release area need to be continued. This lets the
wombat become familiar with the area and know where established burrows are
to escape to if there is danger or to occupy.
Three months before release human contact should cease, except to check food
and water. Don't speak to the wombat or try to touch it.
They should be aggressive.
Wombats due for release should be as
aggressive as this wild wombat with its
fearsome snarl and growl to warn off predators.
(1) page 63
58
Release
Soft Release
Have an opening in the enclosure wall, or a tunnel exiting to the outside world, so
that the wombat can come and go as it pleases. This gives it a familiar place to
return to until it is ready to move out totally on its own.
Hard Release
Wombats must go back into the same gene pool, within 100km from where it was
found.
If there are drastic changes in the habitat 20 kilometres may even be too great.
The release site should be on protected land such as National Park or
conservation area. Permission must be sought prior to release.
Don't release in areas of high population as fighting will occur.
Try to monitor from a distance for about one month after release without human
contact. If they are not feeding they will deteriorate rapidly.
Permanently in Captivity
A yard similar to the pre-release yard can be used.
The temperature needs to be monitored carefully as temperatures > 28oC can
cause death from heat stress.
Wombats can tolerate some direct heat in winter but need a burrow to return to
so as to regulate their temperature.
A permanent enclosure should be as large as possible.
Access to dirt for burrowing must be provided so that natural behaviour can
occur.
Moats as security for an enclosure may not be successful as adult wombats are
good swimmers.
Diet
Similar to a young wombat in rehab but carrots and other raw vegetables may
be added for variety.
Carrots can be fed to permanent captive wombats as there is no risk of them
being poisoned by carrots left as bait for rabbits.
A high proportion of the diet should be native grasses.
Fresh water must be provided daily.
Fresh clover, cabbage leaves or other cabbage family members should never be
fed as they cause gut disturbances which may lead to death.
59
5. Human Impact
Introduction
The human impact on wombats has been devastating. Its range has
decreased and its habitat destroyed.
This is due to a combination of the takeover by introduced animals, both
domestic and feral and land clearing to accommodate the ever increasing
need for human expansion into areas that were once native bush.
Wombats have been declared pests and eradicated; they are killed daily
on the roads and die from diseases caused by introduced animals
Only humans and their actions have eliminated wombats from large
areas.
Wombats and humans have been in conflict since the first settlement.
Wherever land was cleared wombats were killed by poisoning or
shooting.
The introduction of rabbits and their fencing to keep them out has been
one of the greatest problems for wombat populations. Wombats go
straight through the fences or dig underneath leaving the hole wide open
for rabbits to enter. The common wombat is being destroyed so as to stop
them moving within their range and allowing rabbits into pasture.
60
History of Human interaction since 1906
This is a sad tale of man not attempting to live with nature and forcing
eradication of a native animal from many areas.
South Australia
Declared feral in 1912
Full protection given in 1964, except, for damage control.
New South Wales
Considered noxious in parts of NSW until 1959, farmers
obliged to destroy them.
After 1959, unprotected, but not noxious.
After 1973, 'full protection', with exceptions.
Queensland
Protected from 1906
Permits for destruction still available
ACT
No provision for destruction of wombats
61
Western Australia
Considered vermin until the 1960's even though common
wombats don't survive there. This came from a fear of them
being introduced into the wheat belt.
Tasmania
Unprotected until 1970
Land holders may obtain permits to shoot up to 400 on
their land.
Thousands are shot illegally each year.
(1) Woodford pages 187-188
Victoria
Declared vermin in 1906
Bounty in place 1925.
Trappers were employed by local councils and
subsidised by the government.
A bounty of 10 shillings or $1 was paid on each
wombat scalp.
They were:
Trapped in heavy steeled, strong- jawed
traps.
(These snapped on the foot and held on
tightly. Traps may have only been checked
every 1-2 weeks, the wombats dying a slow
and painful death.)
Poisoned
Shot
Between 1950 and 1966 (the last 16 years of the scheme)
64,00 wombats were destroyed for their bounty. Many were
destroyed deep in the forest where they were no problem to
farmers at all.
All crests (11)
62
When the bounty was removed in 1966 they were still
considered vermin. It was obligatory for landholders to
destroy any wombats on their property.
Many farmers ignored this law and attempted to live in
harmony with wombats. As the law was not strictly
enforced some wombats still inhabit areas on or near
private land.
In 1977 they were considered protected wildlife in Western
Victoria but by now there were few left and the protection,
in fact, came too late.
Wombats are still considered vermin east of the Melbourne
to Albury railway line.
In 1984 they were considered protected in most of Victoria
but protests from farmers in 193 parishes pushed for them
to be declared unprotected wildlife,
"in these parishes landholders may take or
destroy wombats' by the use of fumigants, traps or firearms
only on freehold or leasehold property or on Crown land
within one kilometre of each property', except where the
crown land is also part of a national park, where wombats are
fully protected.
In the rest of Victoria, and in the whole of New South Wales
and Tasmania where wombats have been protected since 1974
and 1971 respectively landholders can apply to wildlife
authorities for licenses to allow them to reduce the numbers
by killing some where they are causing damage and their
destruction is necessary to relieve the situation."
(1) Triggs pg 103
Even today despite the changes in legislation many farmers still see wombats as a
pest and wish to destroy them. Many uninformed farmers blame them for the
spread of mange in farm dogs. They may shoot, use illegal traps or fumigate
burrows. A wire netting fence designed to keep rabbits out does not present a
problem to a wombat.
"which either simply pushes a hole through the netting or
digs underneath it. To do this the wombat scoops out a
shallow trough under the wire to lift it up so that the broad
shoulders and neck can squeeze beneath it. Then it stands
up , bending the wire as it does so and making a sizeable hole
under the fence, and walks through into the crop or pasture
or pine plantation or vegetable garden or anywhere else that
suits it. The wombat usually rambles some distance from its
point of entry, so when it leaves it makes another hole."
(1) Triggs page 106
63
Conventional rabbit-proof fencing present no obstacles for
wombats as shown in this picture. Unfortunately the holes
left let rabbits in. On small farms, heavy gates that rabbits
are unable to open placed on the fence in wombat tracks
are successful. For larger properties electric fencing is more
suitable as wombats avoid electric fences after two to three
contacts. (1) page 62
(6) page 62
64
Range
This has declined considerably since European settlement. See section two
on distribution for more details of the changes in range. Introduced
rabbits have contributed to this decline.
" Brian Cooke has investigated this decline and has found
that it was probably caused by rabbits. Native pastures were altered to
such an extent by these pests that wombats could no longer maintain
populations, except in the most favoured parts of their former range.
The effect on the wombat of the changes made in the last 200
hundred years, and the impact of Europeans in general, more
correctly falls under the heading of Disasters"
(1) Triggs pages 9-10
Land Clearing
Wombats live mostly in mountainous and hill areas.
Clearing for grazing continues.
usually all burrows are destroyed, this is easy with a bulldozer.
Some wombats may try to enter newly cropped areas and conflict
with farmers. Here poisons, guns and traps are likely to be used.
Clear felling still occurs for
woodchipping
timber harvesting
planting of pine trees
This all destroys more native forest.
The number of burrows left after clear felling depends upon the terrain.
Wombats often burrow on the banks near creeks and rivers.
It is illegal to clear near stream beds to reduce chances of erosion.
The distance can be 20-200 metres depending upon stream type
and vegetation.
Burrows near stream beds and on slopes too deep for bulldozers are left.
If burrows are in an accessible place destruction is total.
Studies have shown that changes in forestry habits have increased the
possibilities of wombats returning and staying in pine plantations. The thinning
of canopies now allows more native grass to grow.
Wombats can survive in pine plantations but numbers are often lower than
previously.
65
Logging and Clearfelling for Woodchipping
If enough burrows and food remains some wombats can keep a hold on the area.
Where logging and clear felling is followed by 'slash burns' wombats are unlikely
to survive the intensity of the fire and all food sources are destroyed.
This clear felling followed by 'slash burn' to clear the area is devastating
for wombats in terms of food supply even if they go survive the heat of the
fire. (12)
66
Road Kills
A dead wombat by the roadside, yet another victim of human impact. (13)
Wombats continue to use the same crossing point in a home range even if a road
has been built across it. Hundreds of wombats would be killed on our roads each
year.
This wombat continues to use a time old trail despite the attention it is attracting.
(1) page 68
They will often be attracted to roadsides, to graze on grasses planted to stabilise
the roadside.
After rain they are attracted to new growth by the roadside.
After bushfires the only green growth may be by the roadside.
67
Predators
Wild Dogs Dingoes and Foxes
The introduced European Red Fox. (14)
Foxes are capable of chasing and killing animals much larger than themselves.
The wombat can escape down the burrow if there is one nearby. It crouches with
its rump presented towards the entrance by thrusting it up or sideways it crushes
anything that is touching the wombat eg the head. Crushed fox and dog skulls
have been found in wombat burrows.
In the open the wombat can inflict a crushing bite. Its long forward pointing
incisors driven in stabbing lunges can inflict deep severe injuries.
A healthy adult wombat can hold its own against a single dog but not against a
pack.
The most vulnerable wombats are:
young at heel
newly immature, independent
old
weakened adults
68
Introduced Diseases
Sarcoptic Mange
This is spread by foxes, wolves (the dingo is an Asiatic wolf) and
dogs and is a cruel, painful, devastating and usually a death
sentence to wombats who have no natural resistance to the
introduced mite.
It is caused by the mange mite - sarcoptic scabies.
The wombat mite is Sarcoptes scabiei var, wombati. The dog
mite is Sarcoptes scabiei var. canis These mites easily
transfer between dogs, foxes, dingos and wombats.
The mite is 0.2mm- 0.4mm in size. It is easily transmitted
from animal to animal, animal to surrounds and surrounds
that the animal has contact with to the animal.
The Life Cycle.
The male and female mite mate on the skin of the wombat.
The male mite dies.
The female burrows under the skin of the wombat and lays
its eggs in honeycombed tunnels up to several centimetres
long.
The female dies at the end of the tunnel
The eggs are nurtured by the wombat's blood serum along the
tunnel wall.
Eggs hatch into larvae within 3-8 days.
The larvae moult into nymphs still feeding on the blood serum
(clear component of blood)
The nymph moults into an adult.
The adult returns to the skin surface to mate.
The entire cycle, hatching to young takes 2-3 weeks.
if dislodged from the host it can survive until a new host
makes contact with it.
Symptoms
Mange starts to occur where the wombat has come
contact with the mite
The burrowing and movement under the skin causes
scratching day and night depriving the wombat of energy.
Hair loss (alopecia) starts along with scratching and selfmutilation of the skin area.
69
The wombat will scratch until layer of skin are taken off
and it is raw.
The mite tunnels allow serum to seep to the surface of the
skin and scabs form. Lesions and ulcerations occur
The continual scratching for relief opens the wounds to
infection and irritation by insects and f]lies which are
attracted to open wounds.
In severe cases the wound scabs over in a thick layer whilst
the mite continues to breed underneath. The skin becomes
bald and thickened.
The eyes are closed by lesions.
Most of the hair is lost.
Bacterial infection causes pus, which further encourages
insects and fly strike.
Mange is stressful, particularly in juveniles without the
energy or body reserves of adults.
The wombat loses condition very fast:
`
Can't travel far to eat.
Lacks the energy to look for food, water and shelter.
Causing further weakening and a downward spiral in
health.
Secondary infections are occurring and the sustained
increase in the white blood cell count do not kill the mite
but instead lower the immune system and attack the liver
and kidneys causing damage and failure.
70
Ruswell's Burrow
The wombat becomes weak, emaciated and dies
Once infected the wombat can transmit the mite to others. Transfer is made
worse by the sharing of burrows and foxes using wombat burrows.
Mange was not seen in Wombats in Tasmania until 2001 after the illegal
introduction of the European Red Fox across Bass Strait.
(1) Woodford pg 203
Liver Flukes
An infectious bacterial disease where introduced cattle and
sheep are the principle hosts.
Leptospirosis is found on pasture ( particularly swampy)
grazed by contaminated stock. Wombats may share this
grazing area.
It causes serious kidney and liver damage.
71
Toxoplasmosis
This is carried by feral cats.
Wombats are infected by ingesting microscopic toxoplasma
oocysts passed in the faeces of cats.
It develops suddenly and severely, resulting in death.
Poisoning
Rabbits are indirectly responsible for wombat poisoning.
1080 is baited in carrots, oats and pellets.
Wombats may take these and if enough is eaten they may
die.
It is important that hand raised wombats are not fed
carrots as they may develop a taste for them and later be
poisoned.
Trapping
Wombats are subject to slow, painful deaths as a result of
dog, fox and rabbit traps.
Fire
Once again, humans paly a part in this with either illegal
deliberate burns or people who start fires for 'fun',
Wombats if they are down their burrows may survive as the
insulation is good and the temperature is low.
An intense fire will deprive the air of oxygen and even the
wombats deep in burrows will die.
Burrows can be destroyed if they are made under uprooted
trees, if the tree burns the whole structure collapses.
If a wombat survives the fire all familiar scents, food and
many landmarks are gone.
Food sources may now be a long way from the usual range,
causing the wombat to travel, encounter territorial fights
and increase the population burden on the new range.
72
Impact on tourism
At this point the wombat is not important to our tourist industry so there
is not the outcry over loss of habitat and introduced disease and control
by farmers that there tends to be with kangaroos and koalas.
It could be made important though as it has an image of a quaint cuddly
creature not often see. Many overseas visitors request to see a wombat.
Perhaps, as in Tasmania where there is a developing tourist industry
around nocturnal viewing of the Tasmanian Devil a similar niche could be
found with the wombat, creating income for farmers who would then
choose to protect rather than kill wombats.
To the Future
Wombats will never be able to regain the territory and numbers it once
had but we must work to ensure that it at least, stays at the current
population level.
All the human impacts discussed above still exist today, legally or
illegally. The Common Wombats future is not grim but it is far from safe
as humans continue to take habitat and foxes spread mange.
73
BIBLIOGRAPHY
TEXT
1. Triggs. Barbara. The Wombat Common Wombats in Australia University of
New South Wales Press Ltd Revised Edition 1996.
2.Woodford. James. The Secret Life of Wombats The Text Publishing Company
Melbourne Victoria 2001.
3. Lardner- Smith. Jodie. Zoo Vet Nurse Wombats: Handraising, Housing and
Feeding. Wildlife Training Course for Veterinary Nurses 23rd-24th May 1998.
Western Plains Zoo Dubbo.
4.George Helen, Parker Gaylene, Coote Peter, Common Wombats: Rescue,
Rehabilitation, Release 1995
5.Keen, Kathryn Possum and Glider Rescue and Care June 2003
6. Reardon, Mitch Secret World of the Wombat. Australian Geographic, The
Journal of the Australian Geographic Society. Number Thirty April-June 1993
pages 56-69
7. Russell' Burrow Sarcoptic Mange. 2001-2003
www.netspeed.com.au/wombadilliac/mange.htm (permission given in writing by the
author of the website)
8. New England Ecotourism Society
http://www,ecotourism.com.au/wildlifefactsandfigs.asp
(18)
74
BIBLIOGRAPHY
PICTURES
1. Reardon, Mitch Secret World of the Wombat. Australian Geographic, The
Journal of the Australian Geographic Society. Number Thirty April-June 1993
pages 56-69
2. Australian Museum Online. Wombat Skeletons.
www.amonline.net.au/mammals/gallery/gallery12htm
3. Triggs. Barbara. The Wombat Common Wombats in Australia University of
New South Wales Press Ltd Revised Edition 1996.
4.Lewis. Gary, Museum Victoria
www.museum.vic.gov.au/bioformatics/mammals/images
5. Stewart. Sandra and Nunn. Jeremy Rocky Creek Wildlife 2003
6. Common Wombat Footprints Tasmanian Government
www.dpiwe.tas.gov.au/inter.nsf/WebPages/BHAN53F7K7open
7. Wombat Distribution Map
www.geocities.com/csean_au/map.htm
8. Moloney Robyn. General License Holder. Berkeley Vale New South Wales.
1998-2003
9. George Helen, Parker Gaylene, Coote Peter. Common Wombats Rescue,
Rehabilitation, Release. 1995 Illustrations by Anne Bowman.
10. Russell's Burrow 2001-2003
www.netspeed.com.au
11. State Crests Australiana deluxe. True Blue Clip Art. New Horizons
Educational Computing Services. Armidale. Australia
12. Clearfelling
www.wilderness.org.au/.../post-apocalyptic.devistatio.jpg
13. European Red Fox
www.burkesbackyard.com.au/.../images/fox_41.jpg
14. Wombat Trap Karsyl Cottage
www.karsyl.com/traps.phtml
15. Bushfire
www.millhouse.nl/graphics/0207615.jpg
75
BIBLIOGRAPHY
PICTURES cont.
16. Wombat cyberkids
www.kidcyber.com/au/topics/wombat. 2000
BIBLIOGRAPHY
VIDEOS
Video 1: Wombats: Bulldozers of the Bush ABC Video 1993
Video 2: Wee Willie and the Wombat Finishing School
This was recorded by myself from television (without credits) an ABC
production, I think. It tells the story of a wombat from rescue to release at the
home of Gaylene and Rob Parker (WIRES members) in New South Wales
Our Millie, the reason I chose this species. She is our first, but hopefully not
our last, wombat which we are to hand raise.
76

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