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Two instances in South Australia of Sleepy Lizards, Tiliqua rugosa (Gray 1825), feeding on plant species not previously recorded as part of this lizard’s diet

IRCF REPTILES & AMPHIBIANS • 26(1):54–55 • APR 2019
Two Instances in South Australia of
Sleepy Lizards, Tiliqua rugosa (Gray 1825),
Feeding on Plant Species not Previously
Recorded as Part of this Lizard’s Diet
Gerrut Norval1, Robert D. Sharrad1, and Michael G. Gardner1,2
1College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia (norv0003@flinders.edu.au, robert.sharrad@flinders.edu.au)
2Evolutionary Biology Unit, South Australian Museum, North Terrace Adelaide 5000, South Australia, Australia (michael.gardner@flinders.edu.au)
Photographs by the senior author.
54
IRCF REPTILES & AMPHIBIANS • VOL15, NO 4 • DEC 2008 189TABLE OF CONTENTS
TABLE OF CONTENTS
FEATURE ARTICLES
Chasing Bullsnakes (Pituophis catenifer sayi) in Wisconsin:
On the Road to Understanding the Ecology and Conservation of the Midwest’s Giant Serpent ...................... Joshua M. Kapfer 190
The Shared History of Treeboas (Corallus grenadensis) and Humans on Grenada:
A Hypothetical Excursion ............................................................................................................................Robert W. Henderson 198
RESEARCH ARTICLES
The Texas Horned Lizard in Central and Western Texas ....................... Emily Henry, Jason Brewer, Krista Mougey, and Gad Perry 204
The Knight Anole (Anolis equestris) in Florida
............................................. Brian J. Camposano, Kenneth L. Krysko, Kevin M. Enge, Ellen M. Donlan, and Michael Granatosky 212
CONSERVATION ALERT
World’s Mammals in Crisis ............................................................................................................................................................. 220
More Than Mammals ...................................................................................................................................................................... 223
The “Dow Jones Index” of Biodiversity ........................................................................................................................................... 225
HUSBANDRY
Captive Care of the Central Netted Dragon ....................................................................................................... Shannon Plummer 226
PROFILE
Kraig Adler: A Lifetime Promoting Herpetology ................................................................................................ Michael L. Treglia 234
COMMENTARY
The Turtles Have Been Watching Me ........................................................................................................................ Eric Gangloff 238
BOOK REVIEW
Threatened Amphibians of the World edited by S.N. Stuart, M. Hoffmann, J.S. Chanson, N.A. Cox,
R. Berridge, P. Ramani, and B.E. Young .............................................................................................................. Robert Powell 243
CONSERVATION RESEARCH REPORTS: Summaries of Published Conservation Research Reports ................................. 245
NATURAL HISTORY RESEARCH REPORTS: Summaries of Published Reports on Natural History ................................. 247
NEWBRIEFS ...................................................................................................................................................................................... 248
EDITORIAL INFORMATION ..................................................................................................................................................... 251
FOCUS ON CONSERVATION: A Project You Can Support ............................................................................................... 252
Front Cover. Shannon Plummer.
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fugiatis maionsequat eumque
moditia erere nonsedis ma sectiatur
ma derrovitae voluptam, as quos
accullabo.
Back Cover. Michael Kern
Totat et velleseque audant mo
estibus inveliquo velique rerchil
erspienimus, quos accullabo. Ilibus
aut dolor apicto invere pe dolum
fugiatis maionsequat eumque
moditia erere nonsedis ma sectia-
tur ma derrovitae voluptam, as
IRCF
REPTILES & AMPHIBIANS
CONSERVATION AND NATURAL HISTORY
Copyright © 2019. Gerrut Norval. All rights reserved.
WWW.IRCF.ORG/REPTILESANDAMPHIBIANSJOURNAL
The Sleepy Lizard (Tiliqua rugosa) is a large omnivorous
skink that is endemic to southern Australia (Cogger
2014). These lizards usually feed on the leaves, flowers,
and/or fruit of a variety of plants and will also opportunis-
tically feed on invertebrates, small vertebrates, and carrion
(Yeatman 1988; Henle 1990; Dubas and Bull 1991). Herein
we describe two instances of adult Sleepy Lizards feeding on
plants not previously recorded as part of their diet.
At 0945 h on 9 December 2018, the senior author
observed a Sleepy Lizard on Salford Road, a dirt road in
the Mid North Region of South Australia (33°58’05’’S,
139°13’23’’E; 213 m asl; datum: WGS84). The lizard was
next to a Wild Oat (Avena fatua) growing in the road and
when the lizard gaped as a threat display, the inflorescence
IRCF Reptiles & Amphibians ISSN 1098-6324
Fig. 1. A Sleepy Lizard (Tiliqua rugosa) found on 9 December 2018 eating
the inflorescence of a Wild Oat (Avena fatua).
Fig. 2. A Sleepy Lizard (Tiliqua rugosa) found on the roadside on 23 December 2018 surrounded by Wild Sage (Salvia verbenaca), which is occasionally
eaten by these lizards.
55
and leaves of the grass were observed inside its mouth (Fig. 1).
At 1115 h on 23 December 2018, the senior author noticed
another T. rugosa on the roadside (Fig. 2) of the same dirt
road but at a different locality (33°54’47’’S, 139°18’35’’E;
161 m asl; datum: WGS84). While being handled, this lizard
also gaped, and it had fragments of the leaves of Wards Weed
(Carrichtera annua) and Stemless Thistle (Onopordum acau-
lon) in its mouth (Fig. 3). The senior author also observed
signs of recent and past foraging in the vicinity of where the
lizard was caught (Fig. 4).
To the best of our knowledge, neither A. fatua or O.
acaulon have previously been recorded as part of the diet of T.
rugosa. At the time of our observations, South Australia was
experiencing a drought and plant species such as C. annua,
which is commonly eaten by T. rugosa, were either absent
or had stunted growth. Consequently, the lizards likely were
feeding on plants that they would not usually eat due to a
shortage of their preferred food. Our observations contribute
to the list of species that are utilized as food. They also illus-
trate the importance of continued monitoring. For an omniv-
orous opportunistic species such as the Sleepy Lizard, observa-
tions throughout its range, in different seasons, and among
seasons under different climatic conditions are required to
have a thorough understanding of what plant species Sleepy
Lizards exploit for food.
Acknowledgements
The observations above were made by the senior author
while conducting field work as part of his doctoral research,
which was partly funded in 2018 by grants from Friends of
Private Bushland and the Royal Society of South Australia to
Gerrut Norval. Clearance for the research were granted by
the Animal Welfare Committee of Flinders University (No.
E454/17) and the Department of Environment, Water and
Natural Resources of the Government of South Australia
(Permit No. A23436-26).
Literature Cited
Cogger, H.G. 2014. Reptiles and Amphibians of Australia. 7 ed. CSIRO Publishing,
Collingwood, Victoria, Australia.
Dubas, G. and C.M. Bull. 1991. Diet choice and food availability in the omnivo-
rous lizard, Trachydosaurus rugosus. Wildlife Research 18: 147155.
Henle, K. 1990. Notes on the population ecology of the large herbivorous lizard,
Trachydosaurus rugosus, in arid Australia. Journal of Herpetology 24: 100103.
Yeatman, E.M. 1988. Resource partitioning by three congeneric species of skink
(Tiliqua) in sympatry in South Australia. Unpublished Thesis, Flinders
University, Adelaide, South Australia, Australia.
IRCF REPTILES & AMPHIBIANS • 26(1):54–55 • APR 2019NORVAL ET AL.
Fig. 4. Stemless Thistle (Onopordum acaulon) seedlings eaten by a Sleepy
Lizard (Tiliqua rugosa) caught on 23 December 2018. The yellow arrows
indicate fresh leaf damage where the lizard bit off parts of the leaves.
The red arrow indicates old damage to a leaf, likely caused by a lizard on
another day.
Fig. 3. Part of a Stemless Thistle (Onopordum acaulon) leaf is still pro-
truding from the mouth of a Sleepy Lizard (Tiliqua rugosa) caught on 23
December 2018.
ResearchGate has not been able to resolve any citations for this publication.
Article
The diet of sleepy lizards, Trachydosaurus rugosus, from a population near Tickera, South Australia, was determined by direct observations, stomach content analysis and food choice trials. They were found to be opportunistic feeders with a diverse diet of mainly flowers and berries, selected from 27 of the 85 plant species identified on two study plots. They were also found to feed on invertebrates, mainly the introduced land snail, Thebapisana. Availability of different food types changed with season, and the lizard diet adjusted to the changes. The spring home ranges of lizards contained a higher proportion than random, of sampling squares in which common spring food plants were recorded. However, the abundance of food plants makes it unlikely that food resources influence home range size.
Resource partitioning by three congeneric species of skink (Tiliqua) in sympatry in South Australia
  • E M Yeatman
Yeatman, E.M. 1988. Resource partitioning by three congeneric species of skink (Tiliqua) in sympatry in South Australia. Unpublished Thesis, Flinders University, Adelaide, South Australia, Australia. IRCF REPTILES & AMPHIBIANS • 26(1):54-55 • APR 2019