A discussion of the large extinct rodents of Mootwingee National Park, western New South Wales

4 Pages·1995·2 MB·English

by  Murray Ellis

A discussion of the large extinct rodents
of Mootwingee National Park, western New South Wales
Murray Ellis
Royal Zoological Society, Mammal Section, P.O. Box 20, Mosman, Sydney, New South Wales 2088
.4ddress for correspondence: P.O. Box 459, Broken Hill, New South Wales 2880
ABSTRACT
Four large rodent species (Greater Stick-nest Rat Leporillus conditor, Long-tailed Hopping-mouse
Nofomys longicaudafus. Plains Rat Pseudomys australis and Long-haired Rat Ranus villosissimus)
have been identified among the subfossil remains collected at Mootwingee National Park, western
New South Wales. These records are at the periphery of the published distributions for most of the
species and represent an addition to the fauna recorded for the Mootwingee area.
INTRODUCTION were then compared to similar sized material
held at the Australian Museum and descriptions
The rodent fauna of western New South
in Watts and Aslin (1981) to aid in identification.
Wales has suffered a serious decline over the
Some fragments of the House Mouse Mus
last 200 years (Dickman 1993; Dickman et al.
domesticus and the Fawn Hopping-mouse
1993). However, the full extent of the decline
Nofomys ceruinus are the only positively identified
cannot be ascertained without comprehensive
species among smaller rodents (Ellis 1993). The
distributional information on all of the rodents
bulk of the skull material is from Raltw, but at
that occurred there. The only practical methods
least three other large rodents are also present.
available to determine the pre-European fauna
Most of the bones examined have not been
of western New South Wales are the analysis of
assigned to a species as there is little comparative
subfossil material hidden in numerous caves and
material available for some of the rarer or
crevices across the inland, and the writings of extinct species, and the range of variation in the
early explorers and settlers hidden away in more common species need to be accounted for.
archives. Such work by Dickman (1993) has
already shown the diversity of rodents in western Greater Stick-nest Rat Leporillus conditor
New South Wales to be greater than determined
The remains of stick nests in caves and on
by Watts and Aslin (1981). Similar studies in the
ledges across Mootwingee attest to the original
Flinders Ranges (see Turnbridge 1991) have led
presence of a species of Leporillus in the area,
to the listing of 58 mammalian species as having
with Green et al. (1983) studying one such nest
occurred in that area.
in detail. It was during investigations of another
dozen nests that led to the original discovery of
Regurgitated owl pellets recovered from the
ranges in the Mootwingee National Park (31°10'S the owl pellet deposits in 1988 (Ellis et al. 1991).
14271'E) provide a record of the small mammal Sidney Kidman had noted the presence of stick-
nest rats near Broken Hill in the late 19th
fauna of the district (Ellis et al. 1991; Ellis 1992).
Century (Idriess 1936), although Dickman (1993)
Three deposits have been found within the
suspects that it was actually the Lesser Stick-nest
park; two on the eastern side in the Gap Hills
Rat Leporillus apicalis that was seen. Sturt (1847)
and one on the western side in the Bynguano
collected a specimen of Leporillus conditor from
Range. Several thousand bone fragments have
approximately 150 kms south of Mootwingee,
been recovered from the deposits and it will take
and found further nests to the north-west of
some years before all the species are identified
Mootwingee and assumed they were made by
and counts of the numbers of individuals are
the same species (Fig. 1). Subfossil remains have
completed. However, these deposits have
also been collected in the Flinders Rangers
already revealed the existence of bandicoot and
(Tunbridge 1991).
dasyurid species in the vicinity of the park. Many
of these species have not been captured during Maxillary fragments from the owl pellets
recent trapping exercises in western New South confirm the presence of Leporillus conditor within
Wales (Dickman and Read 1992; Dickman el the area. Ranger Sharon Davey of the NSW
al. 1993) and are now considered extinct in the National Parks and Wildlife Service recently, in
state. 1992, found a complete skull of L. conditor from
the Gap Hills in the east of Mootwingee National
The subfossil material collected from Moot- Park, near one of the owl pellet deposits.
wingee also contained a variety of rodent skulls However, the identification of one species of
and dentaries. These bones were sorted into stick-nest rat does not preclude the possibility
groups of similar size and structure. The bones that both species were present in the region.
December 7995 Australian Zoolo~isl,V oi. 30(1) 39
Fig. 1. The distribution of Leporillus conditor in southeastern Fig. 2. The distribution of Notomys longicaudatus in south-
Australia. Solid circles represent Sturt's records, the eastern Australia. The solid circle represents Sturt's
open circle the Flinders Ranges record, and the solid record, the open circle the Flinders Ranges records,
square the Mootwingee record. Stippling shows the and the solid square the Mootwingee records. Stippling
range according to Watts and Aslin (1981). shows the range according to Watts and Aslin (1981).
The combination of historical records and
subfossil materials show that this species was
once widespread in the Mootwingee-Broken
Hill area. The presence of 12 old nests within
300 m of one of the owl pellet deposits also
indicates that a substantial population exisited
within at least part of the park at one time.
Lon g-tai led H oppin g-mou se
Notomys longicaudatus
Sturt (1847) collected a live animal in 1845 in
the Coonabaralba Range, mistakenly described
as being in Queensland by Dixon (1983). This
area is adjacent to Stephens Creek Reservoir,
immediately east of Broken Hill, New South
Wales, and about 100 km south of Mootwingee.
Complete skulls of this little-known large
hopping-mouse were recovered from intact owl
pellets from within the park. Fig. 3. The distribution of Pseud,omyasu .stralisi n southeastern
Australia. The open circles represent subfossil
. This speciesw as little_known in life except that records, solid circles live collections (after Breed and
it was a minor pest in Western Australia (Watts Head (1991)), and the solid square the Mootwingee
and Aslin 1981), but has been found in other records. Stippling shows the range according to Watts
deposits in the arid zone (Smith 1977:' Copley et and Aslin (1981).
al. 1989) (Fig. 2). Given the wide range of
inland fauna. The speciesh as not been collected
locations that live animals were collected from,
alive in New South Wales for over 100 years,
and the increasing number of locations its
but in 1990 was found in northern South Aust-
remains have been found, this speciesm ust have
ralia, almost I 000 km from Mootwingee (Breed
once occupied much of the arid and semi-arid
and Head t99l).
zones of western and central Australia.
Some skulls and mandibles from the Moot-
Plains Raf Pseudomys australis wingee deposits have been assigned to the Plains
Rat. This is the only precisely located record for
The Plains Rat has had a convoluted
western New South Wales with the other kn<,rwn
taxonomic history. The species, or species
record being from the plains of the Darling by
complex, once occurred over much of the south-
easternh alf of Australia (Breed and Head l99l) John Gould (seeD ickman 1993).
(Fig. 3). However, there is a paucity of records There is some variation among the Pseudomys
for New South Wales where early settlement material and there may also be other similar
and development outstripped any study of the sized species of Pseudomyss, uch as P. gouldii or
40 AustralianZ oologistV, ol.3 0(1) December 1995
for the remains of a stick-nest rat nest from the
Gap Hills. The nest they dated was highly
decomposed, burnt and consisted of little more
than "amberat", a solid bitumenous mass,
located in a narrow crevice in a larger overhang.
Nests from nearer the Gap Hills owl pellet site
still had a large amount of stick and twig
associated with them, but only in the narrower
crevices and ledges where goals and macropods
were unable to destroy them. It seemsl ikely that
these more intact nests were much younger than
the radiocarbon dated one.
Live animals of some species found in the
Mootwingee deposits have been found within
200 km of the park over the last 20 years
(Dickman 1993; Denny 1975; M. Denny, pers.
comm.; D. Read, pers. comm.; M. Ellis, pers.
Fig. 4. Tlae distribution of Rattus aillosisshnusi n southeastern obs.) indicating that some of the pellets could
Australia. The solid circle represents Denny's (1975) have been deposited until recently and still
records, the open circle the Garnpung record, and
contain that fauna. The presence of Mus
the solid square the Mottwingee records. Stippling
shows the range according to Watts and Aslin (1981). remains in some pellets gives evidence that some
of the owl pellets were deposited post the invasion
P. glaucus, within the material. Additional of inlzind New South Wales by that species.
comparative material will need to be examined There is the possibility that Mta arrived in Aust-
before all of the bones can be assigned to ralia on early shipwrecks 300 to 400 years ago.
species. However, no Mu,sw ere collected by Sturt (1847)
or by Kreft during the Blandowski expedition
Long-haired Raf Rattus villosissimus (Kreft 1866; Wakefield 1966). This indicates
The Long-haired Rat is currently known from that Mus probably arrived in western New South
Sturt National Park in the far north-west of New Wales with European explorers and settlers in
South Wales (Denny 1975) (Fig. 4). Kidman the latter half of the 1800s, meaning that some
(Idriess 1936) records a swarm of rats, presumably of the pellet material is less than 150 years old.
this species,n ear Lake Cobham in 1883, 130 km Thus it seems reasonable to assume that these
north-west of Mootwingee. Furthermore, Steve four rodent speciesw ere part of the local fauna
Mossfield from the NSW National Parks and of the Mootwingee area at the time of European
Wildlife Service collected mummified remains of settlement of Australia. Only radiocarbon dating
this species from the wall cavity of the old will resolve this point to any greater degree.
Garnpung Homestead 280 km south of Moot-
Three of the four are now extinct in New
wingee. This indicates that the species was
South Wales, with one species being extinct
extant that far south in New South Wales within
Australia-wide (Dickman 1993). These four
the last 1I0 years (the approximate age of the
species were all predominantly vegetarian, with
building).
diets ranging from foliage to seeds (Watts and
The bulk of the skulls recovered from the two Aslin l98l). With the advent of grazing in the
Mootwingee deposits are from Rattus species, area in the 1860s, these species came into
with some being assignable to R. aillosissimw. A competition for food with sheep and goats.
skull and partial skeleton of the Long-haired Rat Human assistance for the introduced species
were also recovered from the remains of an old allowed them to dominate the area. The sheep
stick-nest located in an overhang at the top of population in the Western Division of New South
the scree slopes in the Gap Hills. The nest is Wales reached a figure almost double the current
likely to have been constructed by a stick-nest recommended carrying capacity (Caughley et al.
rat, although some nest building activity has 1987), to the detriment of the native herbivores.
been recorded for other Rattus species (Watts These native rodents fall within the critical
and Aslin 1981). The most likely explanation is weight range of Burbidge and McKenzie (1989)
that during a "plague" period individuals of this indicating that they are susceptible to predation
highly mobile species invaded the scree slopes by introduced predators. With the reduction in
from their more usual floodplain habitats (Watts plant cover due to heavy grazing pressure,
and Aslin l98l). foraging would have required increased exposure
by the animals and these species must have
GENERAL DISCUSSION
become easy prey for introduced foxes and cats
The actual age of the owl pellets is open to as well as native predators. This combination of
question. Using radiocarbon dating techniques changes has been too great for these large
Green et al. (1983) gave an age of I 800 years rodents to survive in the area.
December1 995 AustralianZ oologist, Vol. 30(1) 41
The study of subfossil material from the Burbidge, A. A. and McKenzie, N. L., 1989. Patterns in the
modern decline of Western Australia's vertebrate fauna:
Flinders Ranges is the closest comparable study
causes and conservation implications. Bid. Cm. 50:
(Smith 1977; Tunbridge 1991). The Northern
143-98.
Flinders Ranges and Mootwingee share a similar
Caughley, C.,S hepherd, N, and Short, J., 1987. Kangorom:
latitude, geology and climate (Tunbridge 1991)
lheir ec01og)i and mnagmli n the she$ rangelonds of Aut-
and so the results from the Flinders Ranges mlk. Cambridge University Press: Cambridge.
provide a good starting point for examining the
Copley, P. B., Kemper, C. M. and Medlin, G. C., 1989. The
Mootwingee fauna. The continuing study of the mammals of northwestern South Australia. Rec. S. Awt.
material from Mootwingee narrows the difference Mw. 23: 75-88.
in the number of species recorded from the Denny, M., 1975. Mammals of Sturt National Park,
ranges of the Mootwingee area versus the Tibooburra, New Sourh Wales. Awt. Zool. 18: 179-95.
better-studied Flinders Ranges (Smith 1977; Dickman, C. R., 1993. The bioiogv and rnnmgmrent o/diue
Tunbridge 1991). Some of the species from the rodmrr o/lhe and m in New Soulh Wales. NSW National
more mesic southern end of the Flinders Parks and Wildlife Service: Sydney.
Ranges, such as Common Ringtail Possum Dickman, C. R., Pressey, R. L., Lim, L. and Parnaby, H. E.,
P~erulocheirup e~egrinw,p robably did not occur 1993. Mammals of particular conservation concern in
~hWc estern Division of New South Wales. Biol. Cons-.
in the drier Mootwingee area. However, most of
65: 219-48.
the 58 species of mammals listed by Tunbridge
Dickman, C. R. and Read, D. C., 1992. The biolqgy and
(1991) were found in the Northern Flinders
monognnaf o/doqwri& ofthe a dz one in NmS oufh Wnler.
Ranges and could have occurred in Mootwingee. NSW National Park and Wildlife Service: Sydney.
Only detailed examination of the sub-fossil
Dixon. J., 1983. Long-tailed Hopping Mouse. In The
record will reveal the true composition of the
Compkle Book o f Awholian Mammalr ed by R. Strahan.
fauna of the area. Even so, the area is now Angus and Robertson: Sydney.
known to have had a richer rodent fauna than Ellis, M., 1992. The Mulgara, Dasycercvr ~Ticficaudo( Kreft
was predicted by Watts and Aslin (1981). 1867): a new dasyurid record for New South Wales.
Awt. Zool. 28: 57-58.
Ellis, M., 1993. Extension to the known range of the Fawn
. Hopping-mouse Notomyr cminur in New South Wales.
" , " Awl. Zool. 29: 77-78.
to be an underestimate, and the future for many
Ellis, M., Wilson, P. and Hamilton, S., 1991. The Golden
of the remaining arid zone mammalian species Bandicoot Isoodon aurafvR amsay 1887, in western New
is bleak (Dickman el al. 1993). If any of these South Wales during European times. Azut. 2001. 27:
locally extinct species are to be returned to 36-37.
Mootwingee then the problems of the broad Green, N., Caldwell, J., Hope, J. and Luly, J., 1983. Pollen
habitat requirements, diet and predation risk from an 1800 year old stick-nest rat (Leparillw sp.)
need to be reviewed and resolved. For some it is midden from Cnalta, western New South Wales.
@uunr&r. Aut. 1: 3141.
too late and they can be returned to Mootwingee
only as a lifeless display in a visitor centre. Idriess, I., 1936. The Calfle King Angus and Robertson:
Sydney.
ACKNOWLEDGEMENTS Kreft, G., 1866. On the verrebrated animals of the lower
Murray and Darling, their habits, economy, and geo-
I would like to thank Rangers Sharon Davey graphic distribution. Tram. Phil. Suc. NSW 1862-
and Steve Mossfield for forwarding to me the 1-33.
subfossil remains that came into their possession; Smith, M. J., 1977. The remains of mammals, including
Linda Gibson for confirming the identity of the Notomyr longicaudzfw (Could) (Rodentia: Muridae), in
Garnpung Rattw; Linda Gibson and Tim owl pellets from the Flinders Ranges, South Australia.
Aul. WiM1. Res. 4: 158-70.
Flannery for granting me access to the Austra-
lian Museum collections and space to work; and Stun, C., 1847. Nanatiue of an Expcdifion info Cmlral Awt-
the members of the RZS Mammal Section who mlia. Greenwood Press: New Yark.
attended the two field trips to collect the sub- Tunbridge. D., 1991. Thexfmy" /the Flinders Ranger Mammlr.
fossil remains of the Mootwingee fauna. Kangaroo Press: Sydney.
Watts, C. H. S. and Aslin, H., 1981. The Roden& ofAwtrolk.
REFERENCES Angus and Robertson: Sydney.
Breed, W. G. and Head, W., 1991. Conservation status of Wakefield, N. A., 1966. Mammals of <he Blandowski
rhe Plains Rat Pseudomy owtvnlir (Rodentia: Muridae). Expedition to northwestern Victoria, 1856-57. Pmoc.
Awl. Mamml. 14: 125-28. Rq. Soc. Vk. 79: 371-91.
42 Australian Zoologist, Vol. 30(1)