Possible Evidence of the Southern Brown Bandicoot 'Isoodon obesulus', from Deal Island, Kent Group, Bass Strait, Tasmania

2007·0.57 MB·English

by  Mark, Doran Wapstra

NaturalistNotes
Possible Evidence ofthe Southern Brown Bandicoot
Isoodon obesulus from Deal Island, Kent Group,
,
Bass Strait, Tasmania
Observations
In March 1999 the authors visited Deal although this particular structure is unlike-
Island (Kent Group) to survey the island ly to belong to this species. Further candi-
for burrowing crayfish species. The Kent dates for constructing such a shelter might
Group is located about halfway between include introduced rats such as Rattus
the southern tip of Wilsons Promontory norvegicus, which is recorded for the
and the northern tip ofFlinders Island, and island (Brothers et al. 2001), or even
comprises about six islands, themain three native rats such as Rattus lutreolus, which
beingDeal Island(c. 1577ha) andthecon- is possibly present on the island (Brothers
joined Dover and Erith islands (c. 295 ha et al. 2001). Flowever, given that the nest
and 323 ha, respectively) about one kilo- was in a remote part of the island (i.e.
metre to the west across a channel away from the main settlement) and in
(39°28’S, 147°21’E). Deal Island is a con- quite open vegetation, the possibility ofa
servation area but has been highly modi- rat nest seems remote but is by no means
fied by a long history offire, land clearing impossible.
andgrazing. Rounsevell et al. (1991) indicated that
The pictured shelter/nest (Fig. 1) was the southern brown bandicoot is wide-
located on the eastern side of Deal Island spread throughout mainland Tasmania but
in closed Allocasuarina woodland. Given is absent from all islands except Maria
the size of the structure (see watch for Island (where it is introduced), Bruny
scale), its location on the ground and the Island and “West Sisters Island” in the
type ofconstruction (“interwoven” sheoak Furneaux Group (Hope 1972), where it
needles), combined with the habitat waslastcollectedin 1987.
(grassyAllocasuarinawoodland), it ispos- Brothers et al. (2001) did note that the
tulated that the buildermightbe a southern southern brown bandicoot occurs on Deal
brown bandicoot, Isoodon obesulus. Island and the nearby Erith Island, but no
Unfortunately, no collections of scats evidenceisavailabletosupportthisobserva-
and/or hair were made from within and tion (in the form ofdatabase or museum
around the structure, and no obvious coni- records), although its veracity is not ques-
cal diggingswereobserved inthevicinity. tioned. Ifthe structuredescribed in this note
Other ground-dwelling candidates as does belong to a southern brown bandicoot,
owner ofthe structure are the Tasmanian the observation may be significant because
bettongBettongiagaimardi althoughthere the species is only formally known from
,
are no records of this species from the Inner (West) Sister Island offthe northern
Bass Strait islands (Rounsevell et al. tip ofFlinders Island. Similar structures to
1991), or long-nosed potoroo, Potorous the one pictured have been observed on
tridactylus although the structure appears nearby ErithIsland and despitecamera-trap-
,
to be too small for this species. The ping (remote-controlled nocturnal photogra-
absence ofground predators, such as the phy),theownerswerenotdetected,although
Tasmanian devil Sarcophilus harrisii and introduced rats were (D Pemberton pers.
species ofquoll (Dasyurus viverrinus and comm.), and footprints possibly belonging
D. maculatus), means that the structure to the bandicoot were also observed (D
could even belong to arboreal species such PembertonandB Lazenbypers.comm.).
as the common brushtail possum Hope (1972) and Brothers et al. (2001)
Trichosurus vulpecula or the common listed the common brushtail possum as
ringtail possum Pseudocheirusperegrinus. being present on the Deal Island and the
The latterspeciesoften buildsnests(dreys) nearby Erith and Dover Islands. Brothers
in trees but might construct a nest on the et al. (2001) indicated the long-nosed
ground in the absence of predators. potoroo as being present on Erith Island
Vol. 124 (3) 2007 179
NaturalistNotes
and Hope (1972) reported subfossil collec- Acknowledgements
tions ofthe potoroo from Deal Island from Thanks to Phil Bell, Sally Bryant, Mike
agullyaboveWinterCove. MDroioensseeyn,, SRaorsaehmaMruynkGasl,esD,aGvriedgPHeomcbkeirntgo,nNaincdk
In conclusion, in the absence of other Hans and Annie Wapstra for their thoughts on
evidence such as scats or hairs, it is not the owner ofthe structure. David Pemberton
possible to confirm the identity of the commented on an earlier draft ofthis note, and
owner of this structure. However, the comments ofan anonymous reviewer clarified
information is presented to allow discus- sKeivnegralfoproitnhtesi.r aTshsainsktsancteo dRuorbinKginthgeabnudrrSoewriennga
sion ofits possible significance, especially crayfish surveys, and in particular the inex-
iffurtherevidence comes to light ofsouth- haustiblescrub-bashingeffortsofRob.
ern brown bandicoots, common ringtail
possums orlong-nosed potoroos being pre- References
sent on Deal Island itself or on nearby Br(o2t0h0e1r)sTNa,smPaenmiba’esrtOofnfsDh,orePrIysolrandHs:anSedabHiarldlseyanVd
Erith and Dover Islands. Further surveys other NaturalFeatures. (Tasmanian Museum and
for mammals on the Kent Group using a ArtGallery,Hobart)
variety oftechniques (e.g. hair-tubes, cam- HoPpreocJeeHdi(n1g9s72o)fMthaemRmoavlalsSoofcitehteyBoafsVsicSttorraiiat8i5sl.a1n6d3s-.
era-traps, small and large cage traps, spot- 195.
lighting, scats and tracks survey) appears RoDuinssterivbeultlionDEr,ecoTradysloorfnRaJtiavendterHroesctkriianlgmaGmJm(a1l9s91i)n
tobewarranted. TrTiagsgmsanBia(.19W9i6ld)liTfreaRcekss.eaSrccahts18a,n69d9-O7t1h7e.r Traces: a
ECOtas,M28aSrunkcrWesatpAsvtenruae FUniievledrsGituyiPdreesst,oMAeulsbtoruarlniea)n Mammals. (Oxford
LenahValley,Tasmania7008
Email:[email protected]
and Niall Doran
ResourceManagementandConservation
DepartmentofPrimaryIndustriesandWater
GPOBox44,Hobart.Tasmania7001
eFixgt.en1d.sSftorrucatbuoruetm2a0-d3e0pcrmedboamciknainnttloythoefismhaegoea.kTnheeedrlaeiss.edTShheeoenatkranneceedliessca.t1t0hectmopdcieanmterteeorfatnhde
image are where they rest against a small diameter Sheoak stem. The watch provides a scale. It is
notedthatthestructure isremarkablysimilartothenestofaLong-nosed BandicootPeramelesnasu-
tapictureonpage216ofTriggs(1996).
The Victorian Naturalist
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