The Northern Hairy-nosed Wombat: A Brief History

Presented by Dr Alan Horsup Department of Environment and Resource Management This paper was presented at the 2011 National Wombat Conference

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Dr Alan Horsup Alan Horsup was born in the Shaky Isles across the Tasman. He pursued a few careers from baker to pilot to industrial radiographer before being inspired to join the environmental field in 1983. After completing a Zoology degree at Auckland University, he came to Australia in 1986 to undertake an Honours project on the Allied Rock-wallaby near Townsville. This expanded into a doctoral study the fol-lowing year when he investigated the behaviour and ecology of the species. Alan joined the Queensland Parks and Wildlife Service in 1991 in Rockhampton. For the last 20 years he has managed the recovery program for the endangered northern hairy-nosed wombat. During this time he has overseen a doubling of numbers and been part of the team that established the second population of northern hairy-nosed wombats. Alan lives in Yeppoon on the central Queensland coast with his wife and two daughters.

The Northern Hairy-nosed Wombat: A Brief History

Dr Alan Horsup

Department of Environment and Resource Management

PO Box 3130 Red Hill, Qld 4701

Abstract

The northern hairy-nosed wombat is Queensland’s and one of the world’s rarest mammal

species. Prior to the arrival of Europeans in Australia, the species was distributed throughout

inland eastern Australia from Victoria to central Queensland. By about 1910, the species had

contracted to a small area of central Queensland and in 1971, Epping Forest National Park

(Scientific) was gazetted to protect the last known population. By the mid-1980s, only 35

northern hairy-nosed wombats were believed to survive in this population. Although numbers

had increased to 65 wombats by the mid-1990’s, the population was dominated by older

animals, with males outnumbering females by a ratio of two to one, as evidenced by trapping

studies. In 2000, the first census based on extracting DNA from remotely collected wombat

hair produced a population estimate of 113 wombats. At about the same time, a pack of wild

dogs moved onto the park and killed at least ten wombats. A 20 km predator-proof fence was

built in 2002 to prevent this ever happening again. Two ’hair censuses’ since the fence was

completed have charted an impressive recovery with the 2007 census producing a population

estimate of 138 wombats and a near equal sex ratio. Samples from the most recent hair

census, in late 2010, are currently being analysed.

The increase in numbers and balancing of the sex ratio appears to be mainly due to the

construction of the predator fence. The fence not only prevents predation but also halts

emigration of wombats into unsuitable habitat off the park. As permanent dispersal is mainly

undertaken by females in all three wombat species, prevention of dispersal has helped balance

the sex ratio. Ongoing management actions that are assisting the recovery include

manipulation of pasture in wombat habitat, provision of supplementary feed and water in

wombat habitat, and a full-time caretaker presence on the park to help monitor the wombats

and maintain important infrastructure.

In 2009, the future of the species received a major boost when a second population was

established in south-western Queensland.

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Ancient History

Wombat remains are rare in the fossil record, possibly because their burrowing lifestyle

means that they didn’t travel far from their burrows and rarely visited waterholes or

riverbanks. The semi-arid environment that hairy-nosed wombats inhabit would also not

conducive to sedimentation (Murray 1998). The ancestor of modern wombats, the

Diprotodon, Diprotodon opatum, was a wide-ranging herbivore that grew as large as a small

rhinoceros. It seems unlikely that an animal this large could have created burrows like those

of the modern wombats. The energetic costs of burrow construction and burrow maintenance

would have been prohibitive and the likelihood that even short burrows will collapse increases

with increasing diameter (Woolnough and Steele 2001). The advent of burrowing may have

been promoted by the drying out of the Australian continent during the Pleistocene. Johnson

(1998) argues that a burrowing lifestyle would have been predisposed by the ancient wombat

body form of stout limbs and broad feet with strong claws and by the ancient wombat

digestive system which was adapted to low-quality forage. The reduction in wombat body

size may have occurred just to the point where the physical constraints on burrow size no

longer prevented burrowing. The energy and water saving benefits of constructing burrows

allowed the hairy-nosed wombats, in particular, to occupy those drier areas of the continent

where there was a year-round grass supply.

The ancestors of the modern wombats inhabited all states and territories of Australia (Murray

1998). Ancient hairy-nosed wombat species have been found in the Australian fossil record

dating back 200,000 years into the late Pleistocene Epoch. Recent discoveries of hairy-nosed

wombat fossils in the Northern Territory, dated around 12,000 years old, indicate that hairy-

nosed wombats occurred across all mainland states and territories except Western Australia

(Megirian et al. 2002). There is recent evidence that hairy-nosed wombats occurred as far

west as Winton in western Queensland after a complete skeleton was found in a dinosaur dig

near Winton in 2002. It appears that this wombat had burrowed down amongst 95 million

year old dinosaur bones and then died inside its burrow. Its discovery was met with

excitement, because it was presumed to be a new species of small dinosaur, and then surprise,

when it was realised it was a mammal and then later, a wombat. Uranium isotope dating

suggests that the wombat died at least 26,000 years ago (Hocknull 2005).

Genetic analysis of Lasiorhinus material indicates that the northern and southern species “are

as closely related as other species known to hybridise in the wild” (Taylor et al. 1998). Taylor

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et al. (1998) found that the Epping Forest population possessed only 41% of the

heterozygosity and 36% of the allelic diversity of a comparable sample of southern hairy-

nosed wombat, indicating it had gone through a genetic bottleneck.

It is suspected that prior to the arrival of Europeans in Australia, the northern hairy-nosed

wombat was thinly scattered throughout its range. Based on the few confirmed records the

species’ range covered a narrow inland arc from the Victorian-New South Wales border to

central Queensland (Fig. 1). Its preference for deep alluvial soils with a year-round grass

cover would have further restricted its distribution within this area. To the east it would have

been outcompeted by the bare-nosed wombats, and conditions further west would have been

too dry and hot. There is no evidence that aborigines hunted the species, although the

wombat’s grass diet would have made them good eating. They would have been much more

difficult to catch than kangaroos and wallabies. In south-western Queensland the species was

known as the Yaminon by the local aboriginals.

Post-European History

The 19th Century explorers, Ludwig Leichardt and Thomas Mitchell, almost certainly

observed the burrows and trails of northern-hairy-nosed wombats. In a letter published in the

Sydney Morning Herald on 11 October 1847, Leichardt reports “In this puffy ground, near

clusters of cypress pine, we observed the deep burrows of a probably unknown animal. The

entrance is a large hole four or five feet deep, from the bottom of which passes horizontally

underground. It was about one and a half foot in diameter, and would indicate an animal about

the size of a beaver. Its tracks resembled those of a child two or three years old according to

the observations of my companions. Its dung resembled that of the kangaroo and indicated an

herbivorous animal’s.” (Leichardt 1847). These observations were made near Yuleba Creek

east of Roma in central Queensland.

There is anecdotal evidence of wombats in the Maranoa catchment, particularly in the vicinity

of Mitchell, which is 150 km west of Leichardt’s report of wombat burrows. Thomas

Mitchell, in the diary of his travels through the area, records that near Mt Redcap “the ground

was hollowed out by some burrowing animal, whose tracks had opened the way through the

thick thorny scrub, enabling us to lead our horses” (Mitchell 1848). There are areas along the

Maranoa River with similar geology and vegetation to that recorded along the Moonie River,

the location of the first northern hairy-nosed wombat record in Queensland (see below).

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The first record of a northern-hairy nosed wombat came from a cranium found in Wellington

Caves in NSW. This species was named Phascolomys krefftti and was presumed to be extinct

(Owen 1872). In 1884, four wombat specimens were collected from near Deniliquin in

southern NSW and identified as Phascolomys latifrons, the southern hairy-nosed wombat, and

stored in the National Museum of Victoria (Kershaw 1909). These specimens were later

found to have strong genetic affinities with the northern hairy-nosed wombat, Lasiorhinus

krefftii (Taylor et al. 1994).

In the late 1800’s, a wombat population was discovered on Bullamon Station, on the Moonie

River in south-western Queensland (Fig. 1). Based on the characteristics of the two specimens

collected this wombat was determined to be unique and was named Lasiorhinus gillespiei by

De Vis (1900) in honour of the station manager who sent the specimens to the Queensland

Museum. Further study showed that Lasiorhinus gillespiei (Moonie River) and Phascolomys

krefftti (Wellington Caves) were the same species. The latter ‘fossil species’ was therefore

considered to be still alive again (Kershaw 1909; Dawson 1983). Few specimens were ever

collected from the Deniliquin or Moonie sites and both populations are believed to have gone

extinct by about 1908. The decline of Deniliquin population was apparently hastened by the

gassing and filling of burrows to eradicate rabbits (Dawson 1983).

The first northern hairy-nosed wombat from central Queensland was collected in 1937, but

the species' existence had been known since the area was first settled in 1860 (Crossman

1988). The Queensland Museum contracted a pair of naturalist brothers, Charles and Greensill

Barnard, from Duaringa in central Queensland, to collect a wombat specimen from Epping

Forest Station west Clermont (Fig. 1). The brothers found many burrows on “sandy ridges in

fairly well-timbered country, but carrying very poor grass” but found very few tracks and saw

only three wombats including the one they sent to the museum. Charles Barnard wrote that

“We could see no trace of them feeding out anywhere. They made light pads running from

one burrow to another. The burrows were generally not more than one hundred yards apart

and were mostly in groups of three or four.” (Longman 1939). Longman (1939) concluded

that the Epping Forest wombat was “obviously of the latifrons-gillespiei type” and described

it as the new sub-species Lasiorhinus latifrons barnardi. In took until 1983 for the three taxa,

Phascolomys krefftti, Lasiorhinus gillespiei and Lasiorhinus latifrons barnardi to be placed in

the same species, Lasiorhinus krefftii (Dawson 1983).

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Major reductions in the range of the Epping Forest wombats in the early 1920s, late 1930's,

and mid-1960s, correspond with periods of below-average rainfall in the Epping Forest area

(Crossman 1988, Fig. 2). The most recent contraction of the Epping Forest colony occurred to

the north of the present colony during a drought in the mid-1960's (Crossman 1988). Declines

during droughts were not reversed during better rainfall years, apparently because of

continued grazing pressure by cattle (Crossman et al. 1994). Competition with domestic

cattle, especially during droughts, appears to have been the major reason for the decline of L.

krefftii in the Epping Forest area (Crossman 1988).

Surveys in the 1970s indicated that wombat numbers were highest where cattle grazing was

least heavy. Competition for food, particularly during droughts would have had a major

impact on the wombats. Cattle like to camp under shady trees that large burrows are often

built under and they would have therefore disturbed the wombats and sometimes collapsed

these burrows (Crossman 1988). In severe droughts, when no grasses remained, cattle could

move on to other areas. But because the wombats were dependant on their burrows they either

starved or, if forced to move in search of food without the shelter of burrows, would probably

have perished.

A number of anecdotal reports exist for other Queensland sites in the Tambo, Injune and the

Carnarvon Ranges areas of central Queensland that coincide with areas of sandy soil along the

Belyando and Balonne-Maranoa River systems (Crossman 1988). A second colony may have

existed on the Belyando River near Mt Douglas (80 km north of Epping Forest) until the late

1930s (Fig. 3). This colony is believed to have been distinct from the Epping Forest

population as it was separated from it by a belt of unsuitable habitat dominated by gidgee

scrub and eucalypt forest on clay soils (Crossman 1988). These unconfirmed reports, and the

preference of the Epping Forest population for sandy soils (Gordon et al. 1985), suggest that

the Queensland distribution of L. krefftii was once quite extensive but always patchy (Fig. 3).

Today the northern hairy-nosed wombat is restricted to a single wild population at Epping

Forest National Park (Scientific) in central-western Queensland and one reintroduced

population at Richard Underwood Nature Refuge near St George in south-western

Queensland.

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Gazettal of Epping Forest National park

It was not until the mid 1960’s that further interest was shown in the Epping Forest wombat

population. A Queensland Museum trip in 1965 documented a major contraction of the

species’ range and found that it was restricted to only one location on Epping Forest Station.

The Queensland Government recognised the severity of the situation and the then Queensland

Forestry Department oversaw the gazettal of Epping Forest National Park in 1971 (Gordon et

al. 1985). Epping Forest National Park is located 120 km north-west of Clermont in the

Belyando River drainage system. Gordon et al. (1985) report that the colony previously

extended a few kilometres along several watercourses outside the boundaries of the National

Park. Cattle continued to graze the park until 1981 when a cattle fence funded by the then

World Wildlife Fund was built around the entire park.

The small size of the northern hairy-nosed wombat population at Epping Forest National Park

makes it vulnerable to catastrophes such as drought, flood, disease, and wildfire, and to loss

of genetic diversity, demographic stochasticity, and parasites. Competition with native

herbivores, such as the eastern grey kangaroo, Macropus giganteus, and predation by wild

dogs, Canis familiaris, also pose threats. Because of the highly endangered status of the

wombats, no public visitation is allowed to Epping Forest National Park.

Research on the northern hairy-nosed wombat

1970’s

The first field research on the northern hairy-nosed wombat occurred in the 1970’s when Greg

Gordon and several staff from Queensland Parks and Wildlife Service monitored burrow

activity and distribution on Epping Forest NP from 1975-1982 (Gordon et al. 1985). They

found that burrows were restricted to areas of deep sandy soils and estimated the population

to contain as few as 20 to 30 wombats. They recommended a range of research and

management actions including exclusion of cattle from the park, control of wild dogs, a study

of dietary overlap between wombats and kangaroos, development of an appropriate fire

regime, contingency plans for severe drought including provision of supplementary food, and

a research program to determine population size, structure, reproductive output, and

survivorship.

1980’s

To address some of the recommendations of Gordon et al. (1985), Doug Crossman (1988)

undertook a major trapping study of the wombat population from 1985-87. Fifty-five

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wombats were trapped (26 males, 29 females), of which 29% were sub-adults. During the

study, 81% of females showed evidence of breeding with 56-83% breeding in any one year.

There was evidence that mortality (based on wombat remains found) had decreased since

construction of the cattle fence in 1982. In a brief dietary study, high overlap was found

between wombats, cattle and eastern grey kangaroos. Crossman (1988) estimated that the

population contained about 70 wombats with equal numbers of males and females.

This study was followed by a trapping and radio-tracking study by Chris Johnson in 1988 and

1989. Northern hairy-nosed wombats fed within small home ranges concentrated in the dry

bed of an ancient watercourse and built their burrows along its banks. Wombats had small

core feeding ranges of only 6 ha in winter (dry season) and less than 3 ha in summer (wet

season). Total home range size averaged 25 ha. Wombats averaged 2-6 hours above ground

per night and were least active after summer rains and most active by day in late winter and

spring (Johnson 1991a).

Burrows were arranged in loose clusters and occupied by a group of 4-5 wombats. Each group

member used most of these burrows at some time but simultaneous use of burrows was rare.

Body condition did not vary seasonally, suggesting an impressive ability to survive on a food

resource (grass) which is of low quality, particularly in the long dry seasons. Casual

movements between groups were rare but the incidence of dispersal was quite high,

particularly among adult females. Johnson and Crossman (1991a) suggested that this

behaviour would prevent close inbreeding and may be a form of maternal investment where

females leave their burrow to their young, who are not as capable of creating new burrows. As

for Crossman (1988), Johnson found high incidences of breeding and an increasing proportion

of young animals in the population. Johnson suggested that the habitat at Epping Forest NP

was capable of supporting 3-400 wombats (Johnson 1991a). Females were slightly larger than

males in all dimensions but males had thicker necks, which Johnson and Crossman (1991b)

theorised might be an advantage when males fight inside their burrows.

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1990s

The 1990s was a time of major drought in central Queensland and throughout much of eastern

Australia. Belyando Shire, which contains Epping Forest National Park, was drought-declared

for 78 continuous months from 1 September 1992 to 15 March 1999 (DERM 2011). The

trapping studies of Johnson and Crossman in the 1980s had produced optimistic results

relative to population structure and reproductive levels. However, the next trapping study in

1993 (Horsup 1998) revealed major declines in the proportion of females (1.6 males: 1

female), pouch young, young-at-heel and juveniles in the population (Table 1). The decline in

reproductive levels was clearly drought-related. It was hoped that the skewed sex ratio was an

artefact of trapping but there was no obvious reason why this would not have also occurred in

the 1980s, unless the drought was causing some form of female-biased mortality.

A full mark-recapture analysis of population data collected during the trapping studies of the

1980s (Crossman 1988; Johnson 1991b) and 1993 (Horsup 1998) produced population

estimates of 67 (1985-86), 62 (1988-89) and 65 (1993), respectively (Hoyle et al. 1995). The

lack of any increase in numbers over this period, the male-biased sex ratio and the declining

proportion of breeding females and juveniles were worrying trends. These and the continuing

drought led to the decision to establish a captive breeding population of northern hairy-nosed

wombats at Western Plains Zoo in 1996. The first wombat transferred to the zoo did not settle

well into captivity and tragically died of a twisted bowel. This brought the captive program to

an end.

A fourth major trapping study was undertaken in 1999 (Horsup, unpublished data). The

worrying decline in the proportion of females had worsened, with 28 males and only 13

females captured (2.15 males: 1 female). However, a comparison of reproductive data

between the four trapping studies provided a more optimistic result (Table 1). While there was

a major decline in reproductive levels from the 1980s to 1993, there were signs of a recovery

by 1999, particularly in the proportion of juveniles in the population. This indicated that the

population was responding to the better rainfall and pasture conditions.

2000s

After several years of development, the first full ‘hair census’ was undertaken in September

2000. The technique, developed by Andrea Taylor (Sloane et al. 2000) is based on extracting

DNA from wombat hair collected on double-sided sticky tape strung at about wombat

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shoulder height across the entrances to active wombat burrows. The theory is that as the

wombat crouches to pass under the tape, some hairs with follicles attached are removed by the

sticky tape. The seven day sampling technique was developed to produce more accurate

population estimates without the need for stressful (to the wombats) six month-long trapping

studies.

Unfortunately, the sex ratio revealed by the 1999 trapping study (2.15 males: 1 female) was

confirmed by the 2000 hair census (2.25: 1). On a positive note, the 2000 hair census

produced a population estimate of 113 northern hairy-nosed wombats, a 74% increase on the

1993 estimate of 65 (Banks et al. 2003). Tragically, however, the 2000 hair census coincided

with the arrival of a pack of wild dogs on Epping Forest National Park. Over a two-week

period, the remains of seven wombats were found. Genetic analysis of tissue from the

carcasses indicated the wombats were six males and one female. Three wombats were known

from trapping: the two males were at least 18 and nine years old and the female was at least

17 years old. Three wombats were unknown from trapping studies but skull size indicated one

was a sub-adult and the other two were adults. Five of these six wombats were therefore

adults. The seventh wombat was represented by a piece of intestine. This wombat had not

previously been trapped and no estimate of size could be made. The absence of juvenile

carcasses was unexpected but if predation of juveniles did occur it would suggest that these

were not found because they were totally eaten or carried away and not found by DERM staff.

The number of carcasses found was therefore considered a minimum.

Upon discovery of the first dead wombats, a major wild dog baiting and trapping program

was instigated. In addition, a permanent presence in the form of caretakers was established on

Epping Forest National Park to monitor sand plots at major park intersections. Despite the

heightened alertness and control program, three more northern hairy-nosed wombats were

killed by wild dogs (one in April 2001; two in August 2001). At least 10 northern hairy-nosed

wombats, or 10% of the population, were therefore lost to predation in less than one year.

As a result of the predation events in 2000 and 2001, the Queensland Government provided

funding to build a 20 km x 1.8 m wild dog fence around all wombat habitat on Epping Forest

National Park. This was completed in 2002 and has been a major success. In addition to

excluding wild dogs, the fence also serves to prevent wombats from dispersing off the park.

The park is surrounded by cleared cattle country on black soil plains and there is no intact

wombat habitat for many kilometres in any direction. The prevention of dispersal off the park

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may be the reason for the rapid return of the sex ratio to parity that has been documented in

subsequent hair censuses.

There have been three more hair censuses since 2000. The census immediately after the

predation event recorded a decline from 113 to 90 wombats (Taylor, unpublished data).

However, the 2005 and 2007 censuses documented an impressive recovery to 115 wombats

(Taylor 2007) and then 138 wombats, respectively (Taylor 2009; Fig. 4)). Equally as pleasing

has been the recovery of the female proportion of the population (Fig. 5). From a ratio of 2.23

males: 1 female in 2000, the sex ratio had returned to near parity in 2005 (1.23: 1) and to a

slight female bias in 2007 (1: 1.13).

It has been shown in all three wombat species that females are the permanent dispersing sex

(northern hairy-nosed wombat: Johnson 1988; bare-nosed wombat: Banks et al. 2002;

southern hairy-nosed wombat: Walker et al. 2008). The return to parity of the sex ratio

appears to be strongly linked to the inability of females to disperse off the park. Wombats

regularly dig holes under the predator fence at Epping Forest National Park. None have ever

escaped and it is difficult to sex wombats using infra-red remote cameras. However, we have

proof that one wombat digging under the fence was a female because she wore a left ear tag

(all adult wombats trapped in 1999 were tagged: females on the left ear, males on the right).

The predator fence also created the need for a permanent human presence on the park to

monitor the fence. The subsequent caretaker program has also provided the ability to

undertake other important conservation actions. These include providing supplementary feed

and water to the wombats. Water was provided inside the predator fence because the fence

prevents access to water sources previously available to the wombats and was considered

important for maintaining the population during times of drought. Getting the wombats to

take supplementary food and water had never succeeded, partly because of the conservative

nature of northern hairy-nosed wombats and partly because of the irregularity of park visits by

researchers and rangers. It didn’t take long for the wombats to learn to use the feed and water

stations once these were provisioned regularly. This has a direct benefit for the wombats but

also means that in the event of a major drought or wildfire, and when being translocated to

new sites, the wombats are already attuned to supplementary feed.

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The introduction of disease into the northern hairy-nosed wombat population is considered a

major threat to the species. Measures taken to alleviate this threat include restricting entry to

Epping Forest National Park to personnel directly involved in the recovery program and

ensuring the health and cleanliness of these people, their clothes and vehicles, the use of

sterile techniques when handling wombats, including the wearing of sterile gloves, and

disease monitoring of trapped wombats.

Existing Conservation Measures

The focus at Epping Forest National Park is now on protecting and managing the wombat

population to maximize its reproductive growth and provide recruits for new wombat

populations as they are established. The major management actions being implemented to

achieve these aims are:

• exclusion of cattle (since 1981)

• exclusion of wild dogs (since 2002)

• exclusion of wild fires, weeds and disease

• provision of supplementary food and water

• manipulation of pasture in wombat feeding areas

• monitoring of wombat activity at burrows and feed stations

• monitoring of wombat diet

• restriction of access to management and research personnel only

In 2006 a successful trial translocation was undertaken on Epping Forest National Park. In

2009, the first northern hairy-nosed wombats were reintroduced into south-western

Queensland where they had disappeared 100 years previously. These conservation actions are

reported by Harper (2011) in this volume.

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References

Banks, S.C., Skerratt, L.F., and Taylor, A.C. (2002). Female dispersal and relatedness structure in common wombats (Vombatus ursinus). Journal of Zoology London 256: 389-399. Banks, S.C., Hoyle, S.D., Horsup, A., Sunnucks, P., and Taylor, A.C. (2003). Demographic monitoring of an entire species (the northern hairy-nosed wombat, Lasiorhinus krefftii) by genetic analysis of non-invasively collected material. Animal Conservation, 6, 101-107. Crossman, D.C. (1988). Population ecology and diet of the Northern Hairy-nosed Wombat, (Lasiorhinus krefftii (Owen)). Report to World Wildlife Australia. Crossman, D.C., Johnson, C.N., and Horsup, A. (1994). Trends in the population of the Northern Hairy-nosed Wombat Lasiorhinus krefftii in Epping Forest National Park, central Queensland. Pacific Conservation Biology 1: 141-149. Dawson, L. (1983). The taxonomic status of small fossil wombats (Vombatidae: Marsupialia) from Quaternary deposits, and of related modern wombats. Proceedings of the Linnean Society of New South Wales 107: 99-121. DERM (2011). Drought situation reports for Queensland shires http://www.longpaddock.qld.gov.au/queenslanddroughtmonitor/queenslanddroughtreport/index.php De Vis, C.W. (1900). A new species of hairy-nosed wombat. Annals of the Queensland Museum 5: 14-16. Gordon, G., Riney, T., Toop, J., Lawrie, B., and Godwin, M.D. (1985). Observations on the Queensland Hairy-nosed Wombat Lasiorhinus krefftii (Owen). Biological Conservation 33: 165-95. Hocknull, S. (2005). Poor Wally. Australian Age of Dinosaurs Annual 3: 66-83. Horsup, A. (1998). A trapping survey of the northern hairy-nosed wombat, Lasiorhinus krefftii. Pp 147-55 in Wombats (Ed.s R.T. Wells and P.A. Pridmore). Surrey Beatty and Sons, Chipping Norton 1998. Hoyle, S.D., Horsup, A., Johnson, C.N., Crossman, D.C., and MacCallum, H. (1995). Live trapping of the northern hairy-nosed wombat (Lasiorhinus krefftii): Population-size estimates and effects on individuals. Wildlife Research, 22(6), 741-55. Johnson, C.N. (1991a). Utilisation of habitat by the Northern Hairy-nosed Wombat, Lasiorhinus krefftii. Journal of Zoology London 225: 495-507. Johnson, C.N. (1991b). Behaviour and ecology of the northern hairy-nosed wombat Lasiorhinus krefftii. Internal Report QNPWS, 1991. Johnson, C.N. (1998). The evolutionary ecology of wombats. Pp 34-41 in ‘Wombats’ (Ed.s R.T. Wells and P.A. Pridmore). Surrey Beatty and Sons, Chipping Norton 1998.

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Johnson, C.N., and Crossman, D.C. (1991a). Dispersal and social organisation of the Northern Hairy-nosed Wombat, Lasiorhinus krefftii. Journal of Zoology London 225: 605-613. Johnson, C.N., and Crossman, D.C. (1991b). Sexual dimorphism in the Northern Hairy-nosed Wombat, Lasiorhinus krefftii. (Marsupialia: Vombatidae). Australian Mammalogy 14: 145-146. Kershaw, J.A. (1909). Notes on the hairy-nosed wombat Phascolomys latifrons Owen. Victorian Naturalist, 26: 118-119. Longman, H.A. (1939). A central Queensland wombat. Memoirs of the Queensland Museum 11: 283-287. Leichardt, L. (1847). Diary of travels in central Queensland. Letter published in the Sydney Morning Herald on 11 October 1847. Megirian, D., Murray, P.F., Latz, P.K., and Johnson, K.A. (2002). The Mygoora local fauna: A late Quaternary vertebrate assemblage from central Australia. The Beagle. Records of the Museums and Art Galleries of the Northern Territory, 18: 77-93. Mitchell, Y.L. (1848). Journal of an Expedition into the Interior of Tropical Australia: In Search of a Route from Sydney to the Gulf of Carpentaria. Murray, P.F. (1998). Palaeontology and palaeobiology of wombats. Pp 1-33 in ‘Wombats’ (Ed.s R.T. Wells and P.A. Pridmore). Surrey Beatty and Sons, Chipping Norton 1998. Owen, R. (1872). On the fossil mammals of Australia. Part VI. Genus Phascolomys Geoffr. Philosophical Transcripts of the Royal Society, 162: 173-196. Sloane, M.A., Sunnucks, P., Alpers, D., Beheregaray, L.B., and Taylor, A.C. (2000). Highly reliable genetic identification of individual northern hairy-nosed wombats from single remotely collected hairs: a feasible sampling method. Molecular Ecology 9: 1233-1240. Taylor, A.C., Sherwin, W.B., and Wayne, R.K. (1994). Genetic variation of microsatellite loci in bottlenecked species: the northern hairy-nosed wombat Lasiorhinus krefftii. Molecular Ecology 3: 277-290. Taylor A.C., Alpers, D., and Sherwin, W.B. (1998) Remote censusing of northern hairy-nosed wombats via genetic typing of hairs collected in the field. In: Wombats (Ed.s R.T. Wells & P.A. Pridmore). Surrey Beatty & Sons: Chipping Norton, pp. 156-164. Taylor A.C. (2007). Final report on 2005 hair census. Report to Queensland Environmental Protection Agency. Taylor A.C. (2009). Final report on 2007 hair census. Report to Queensland Department of Environment and Resource Management. Walker, F.M., Taylor, A.C., and Sunnucks, P. (2008). Female dispersal and male kinship-based association in southern hairy-nosed wombats (Lasiorhinus latifrons). Molecular Ecology, 17, 1361-1374.

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Woolnough, A.P. and Steele, V.R. (2001). The palaeoecology of the Vombatidae: did giant wombats burrow? Mammal Review, 31, 33-45. Figures and Tables Table 1. Comparison of reproductive data from trapping surveys of L. krefftii in 1985-87 (Crossman 1988), 1988-89 (Johnson 1991a), 1993 (Horsup 1998) and 1999 (Horsup, unpublished data). The number of young-at-heel was estimated from the number of captured females with lactating teats but without pouch young. Note that proportions of females in 1985-87 add to more than 1.00 because some individuals were captured at different times with pouch young and without pouch young but lactating. (Adult females are wombats > 1 m in body length; juveniles are < 1 m). TRAPPING ADULT FEMALES POUCH YOUNG YOUNG-AT-HEEL JUVENILES STUDY Number Number Proportion1 Number Proportion1 Number Proportion2 1985-87 22 10 0.45 14 0.64 17 0.31 1988-89 15 6 0.40 9 0.60 11 0.27 1993 10 1 0.10 3 0.30 8 0.20 1999 9 2 0.22 2 0.22 12 0.29

1 As a proportion of the number of adult females 2 As a proportion of the number of wombats trapped (excluding pouch young)

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Figure 1. The estimated distribution of the northern hairy-nosed wombat when Europeans arrived in Australia, extrapolated from the three locations at which it has been recorded.

Figure 2. The Epping Forest region, showing the ancient watercourse along which all currently active burrows of L. krefftii occur and the boundary of Epping Forest National Park. Areas formerly occupied are indicated by the approximate dates at which wombats disappeared (after Crossman 1988).

Deniliquin

Epping Forest

Moonie River

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Figure 3. The distribution of confirmed () and unconfirmed () records of L. krefftii in Queensland (from Crossman 1988).

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Figure 4. Number of active wombat burrows in each year (dashed line) and nine wombat population estimates from 1974 to 2010 (solid line; Gordon et al. 1985; trapping census, Hoyle et al. 1995; hair census, Banks et al. 2003 and unpublished data).

Figure 5. Sex ratios detected in four trapping studies (1985-1999) and three hair censuses (2000-2007). Males (white); females (grey). Dotted line represents parity of the sexes.