predation by a Black-palmed Monitor Varanus glebopalma (Mitchell, 1955).
The Black-palmed Monitor Varanus glebopalma
is a moderately large, streamlined monitor confined to tropical far
northern Australia. Saxicoline, the species inhabits
(also quartzite rock e.g. Mt Isa district, Qld) ranges and escarpments,
particularly those adjacent to watercourses within gorges (pers. obs.). The
following account is based on an adult specimen running down and
subsequently consuming a sub-adult female Gilbert’s Dragon Amphibolurus gilberti.
Gorge Nature Reserve in the ‘Top End’ of the Northern
The reserve is located 32km via unsealed road south-west of the mining
township of Pine Creek (13°49’, 131°50’).
sandstone escarpment with intersecting gorge falling away to stepped
cliffs with attenuated slopes. Vegetation cited from Kerle,
1996; “On the undulating plateaux and plains are open forests
with mixed stands of Darwin woolly butt Eucalyptus miniata
and stringybark E.
tetrodonta, with a shrub layer and ground layer dominated
by sorghum species. Other species include fan palm Livistonia humilis
and zamia palm Cycas
armstrongii. Other associations on the
undulating country include northern box E. tectifica,
round-leaved bloodwood E.
latifolia and ironwood Erythrophleum chlorostachys
with fan palms and tall grasses such as sorghum and giant spear
10th November 1991. Time:
18:30-19:00hrs (Central Standard Time). Temperature:
34°C, clear, no breeze, relative humidity 80% (approx.). An adult Varanus glebopalma
was observed actively foraging along the Umbrawarra creekbed at
twilight. The species is opportunistic in regards to activity
patterns. Individuals may be sighted diurnally active at any
period (per. obs.), in addition to crepuscular and nocturnal behaviour
(Shea et al., 1988).
hiking along a walking track running parallel to the creekbed, my
attention was drawn by the rustling of foliage a few metres to my
left. A medium-sized agamid subsequently burst through the
undergrowth and bolted across the path less than one metre in front me
with an adult Varanus
hot on its heals. Both lizards covered some thirty metres of
terrain; along the sandy creekbed, across a sandstone overhang and atop
a boulder strewn slope where the chase ended abruptly. Amphibolurus gilberti are
very swift runners and the distance covered took no longer than five
The goanna had seized the agamid around the mid-body and lowered its head
into the sandstone in a manner that pinned the victim onto the
substrate. It then manipulated the dragon’s anterior half
the jaws and swallowed the prey head first and struggling. It
during the swallowing process that the species of unidentified agamid
A sight and subsequent
run down feeding approach is employed by all the swift species of
Varanids and some Elapid genera (eg.; Pseudonaja, Demansia).
are highly adapted in regards to this technique due to their slender
build and extreme agility when mobile on uneven surfaces.
Encyclopedia of Australian Animals - Reptiles. Collins/Angus
and Robertson Pty Ltd, Pymble, NSW, Australia. 495pp. Kerle,
J.A. 1996. Bioregions
of the Northern Territory. Draft report Conservation Commission of
Northern Territory, Palmerston, Northern Territory. Shea,
G., Weigel, J., Hardwood, A., Floriani,, H. Hemsley, C. 1988. Notes on the
Herpetofauna of Mitchell Plateau, W.A. Herpetofauna 18(1):16. Wilson,
S.K. and Knowles, D. 1992.
Australia’s Reptiles - A Photographic Guide to the Terrestrial Reptiles
of Australia. Collins/Angus and Robertson Pty Ltd, Pymble,