Posted on May 31, 2012 at 4:20 AM |
MEGALANIA PRISCA: DRAGON OF THE AUSTRALIAN OUTBACK
By Aaron Justice
In this day and age, Australia is thought of as desert filled with eucalyptus trees and cotton plantations. The animals usually associated with this continent are koalas, kangaroo, wombats, and crocodiles, some of the largest to be found. There used to be other animals, commonly referred to as megafauna, that roamed this continent before being wiped out by plague or man.
These were nightmarish versions of the creatures that we have today. Australia once held 10-foot tall kangaroos that fed on flesh rather than vegetation, and at one time had monitor lizards that dwarfed the Komodo dragon. This was Megalania prisca, a reptile reaching 30 feet in length and weighing at least 1,000 pounds or more. The Komodo dragon is roughly the size of a lion, but Megalania was bigger than an average dairy cow.
Extinct
Megalania is listed with the many casualties of the Ice Age. Or is it extinct? The creature has been sighted many times in the last century, and some sightings suggest that it lives also in New Guinea.
During the middle of the day, a surveyor returned to his truck. Tired, he wanted nothing more than to go home. He spied what he thought was a fallen tree near his car. Blaming his fatigue for his lack of details he climbed in his car and slammed the door. The "log" suddenly bolted away! It ended up being a lizard of 15 feet in length. Australian cryptozoologist Rex Gilroy is convinced these creatures are still alive and it is only a matter of time before one is captured or killed and brought in.
As recently as the late '70s there have been Megalania sightings. In July 1979, Rex Gilroy was informed of footprints of the creature found in a recently plowed field. Across the field were 30 or so tracks from what looked like an enormous lizard. Rain had ruined most of the tracks but Gilroy was able to make a plaster cast of one that had been preserved. The footprint looked surprisingly like something that might have been made by a Megalania.
Also in 1979 a sighting of Megalania arose, this time by the best possible witness. Herpetologist Frank Gordon, after conducting some field work in the Wattagan Mountains in New South Wales, returned to his vehicle. After starting his engine he saw, what he at first thought was a log, scampering off. It ended up being a lizard of some 30 feet or more in length.
Another incident includes a farmer who observed a gigantic lizard walking along one of his fields. It walked along a wire fence, so the farmer used a set of fence posts as a guide. His estimate of the beast was a length of twenty to twenty-five feet. The size corresponds with Megalania.
Megalania might not be constrained only to Australia—some sightings suggest it may live in New Guinea. A French priest in the 1960's was traveling up river with a native guide in order to reach his mission. During the trip he spotted a large lizard lying on a fallen tree in the sun. He told the native to stop, but being badly frightened, the native continued the journey. The priest returned to the spot the following morning and measured the tree. It was 40 feet long, yet the lizard almost matched it.
Whether or not Megalania is still alive today is uncertain, but until a dead body, or perhaps a living one, is brought in we will forever find it in textbooks as an extinct animal of prehistoric times.
Some years ago a Central Queensland farmer recovered a number of unusual bones on his property. Believing he had made an important find he gave the bones to university paleontologists in Brisbane. The bones caused a sensation among Australian paleontologists; not because they were from the giant Australian monitor lizard Megalania prisca Owen, believed extinct at least several thousand years, but because they dated as recent as 300 years old!
This disclosure implies that, if these huge monsters were still roaming Queensland's interior a mere 300 years ago, then claimed sightings of these reptiles in modern times in remote areas of Australia suggest Megalania is far from extinct. Needless to say, the find was quickly "hushed up".
After all, it is embarrassing to have a 23 foot (7 meter) or more, 1,300 pound giant monitor lizard species already declared 'extinct' by 'competent' scientists, continuing to survive, when 'expert' opinion dictates it died out with the rest of the Australian megafauna at the close of the last ice-age!
That is the reasoning of the conservative scientific community, who continue to argue that no animal species remain undiscovered, because the entire continent has been completely explored and mapped long ago, making it impossible for any 'unknown species to have escaped detected by science.
This dogmatic view is in error. True, Australia has been explored and mapped from the air; yet there still remain thousands of square kilometres around this continent, consisting of virtually inaccessible mountainous forest country where any 'unknown' or 'extinct' species could easily survive, hidden from modern human detection.
Australia is not alone in traditions of giant lizards. The Komodo Dragon of Indonesia can reach up to 3 metres in length, while in New Zealand Megalania-sized monsters are a commonplace tradition among the native population. it is claimed that similar lizard monsters still inhabit the Solomon Islands.
The average skull of a full-grown Megalania was about 2.5 feet in length (compared to the 2 inch long skull of a living goanna) and housed ferocious teeth. Little wonder it has been named the "ancient giant butcher". This reptilian nightmare preyed upon animals large and small, including stone-age-man.
Megalania was once believed to belong to a distinct monotypic genus and called Megalania prisca, (Greek for "giant roamer"), "in reference to the terrestrial nature of the great Saurian" (Owen, 1859)). Its placement as a valid genus remains controversial, with many authors preferring sinking the genus into Varanus (Molnar, 2004), which encompasses all living monitor lizards. The first aboriginal settlers of Australia would certainly have encountered living Megalania.
Size of the Megalania
Lack of enough fossil material has made it very hard to determine the exact dimensions of Megalania . (Molnar, 2004). Conservative estimates place the length of the largest individuals at a little over 7 meters (23 ft), with a maximum conservative weight of approximately 1940 kg (4,268 lbs [Molnar, 2004]). Average sized specimens would have been a leaner, but still impressive, 320 kg (704 lbs). Megalania was the largest land-dwelling lizard to have ever lived, and a fearsome predator as well as a scavenger. Judging from its size, Megalania would feed mostly on medium to large sized animals, including any of the giant marsupials like Diprotodon along with other reptiles, small mammals, and birds and their eggs and chicks.
It had heavily built limbs and body and a large skull complete with a small crest in between the eyes, and a jaw full of serrated blade-like teeth. Due to its size and similarities to the Komodo Dragon, a relationship between the two species has been suggested. In reality however, Megalania's closest living relative is the perentie, Australia's largest living lizard, not the Komodo Dragon.
Live Megalania
There have been numerous reports and rumors of living Megalania in Australia, and occasionally New Guinea, as recently as the mid 1990s. Australian cryptozoologist Rex Gilroy has stated that Megalania is still alive today, and it is only a matter of time until one comes in. Aside from stories and eyewitness accounts, the only suggestion that Megalania might still be alive today is plaster casts of possible Megalania footprints that Gilroy made in 1979. However, this view is not accepted by most scientists, and it has been pointed out that supposed sightings of this lizard did not begin until after its initial discovery.
References
Molnar, R. 2004. Dragons in the Dust: The Paleobiology of the Giant Monitor Lizard Megalania. Indiana University Press.
Owen, R. 1859. "Description of Some Remains of a Gigantic Land-Lizard (Megalania prisca, Owen) from Australia." Philosophical Transactions of the Royal Society of London. 149: 43-48. [1]
Wroe, S.: A review of terrestrial mammalian and reptilian carnivore ecology in Australian fossil faunas, and factors influencing their diversity: the myth of reptilian domination and its broader ramifications. Australian Journal of Zoology 50: 1–24. doi:10.1071/ZO01053 PDF fulltext
GIANT REPTILIAN MONSTERS IN THE AUSTRALIAN BUSH
New South Wales Reports
According to Aboriginal tradition, a 'horny-skinned goanna bunyip" is said to have existed in New South Wales and elsewhere across Australia under a variety of different names in the long-ago Dreamtime. It was described as being of enormous size and smelling "terrible". Their rock engravings and cave paintings across the continent clearly depict these and other reptilian monsters, but more on that matter later.
Aboriginal rock engravings depicting Megalania near Sydney and the central coast of New South Wales date as recently as 3,000 years—the age of some fossil fragments of the creatures found in various parts of eastern Australia, if not elsewhere.
We now turn to the north coastal and inland districts of New South Wales where Aboriginal people from most ancient times were well-acquainted with the giant monitors which they called "Mungoon Galli".
However, they appear to have confused these up-to-30-foot-long reptiles with another, larger beast, which they claimed to have reached the astounding length of 50 feet! That such a monstrous form could still survive out there in those wilds seems preposterous, but there are Aborigines who claim they do!
Even if extinct today, perhaps long ago in ice-age times, and earlier, such a species existed. And, if so, perhaps its fossil remains may yet turn up. These monsters were monitors in every detail. Aborigines say their legs were as much as six to seven feet tall when standing and in the walking position. They had a massive head at least four feet in length and a long thick neck, much like a monitor's, which reached a length of around 10 feet. The body reached about 20 feet in length, matched by a long thick tail of the same length.
"These monster-goannas once roamed the whole continent far back in the Dreamtime. Our people used to hunt these monsters in big parties, but hunters had to be careful; for if you were caught, these big fellas would pick you up in their mouths and eat you," said one old Taree Aborigine to a researcher back in the early 1950s.
Like their smaller 30-foot counterparts, they were said to overturn trees of reasonable size. Even today, when a large tree is heard to fall in the forest depths by day or night, Aborigines will say it is the work of a "Mungoon Galli".
Over the years some people have claimed to have found massive footprints of these creatures, but if so, no photographs or casts have been forthcoming. But there are genuine traditions of the monsters among the Aborigines, and until the terrain in which they are said to live can be explored properly, let us at least keep an open mind on the matter.
Aborigines say that strange noises heard near waterholes and certain forest areas near Taree and back of Kempsey are the sounds made by giant monitors, and they will not go anywhere near these places for fear of being caught and eaten by one of these reptiles.
There is a story from the Cessnock district about an incident said to have taken place in late December 1978. In a far paddock on his property, a farmer spotted a gigantic goanna-looking reptile ripping up a cow with its massive jaws and teeth.
The farmer (who did not wish his name to be known) was in a Jeep at the time. He raced off for the house and phoned up mates who, within the hour, descended on the property with their cattle dogs in pick-ups and Land-Rovers, armed with rifles. The location borders swamplands on the edge of thick-forested valleys and mountain country, and it was from there that the monster had obviously emerged.
By the time the search party arrived, all they could find was the half eaten cow, much blood, and many large indistinct tracks in the grassy ground. However, other squashed-about tracks and the marks of a massive tail could be seen on the swamp edge leading into the water. The dogs, as well as the men, refused to go any further.
Using nearby fence-posts to line up the creature at the time of his sighting, the farmer estimated that it was a good 35 feet (10.6 metres) in length, and nine feet or so tall on all fours, counting the great body of the creature. However, few people believed him. Some argued that he must have butchered the cow himself and manufactured the tracks. If this was so, he certainly did a good job. But there are some strange things happening out in those mountains, and I for one am not laughing.
Over the years, inhabitants of the Cessnock district have often talked about enormous 30-foot reptiles that they maintain inhabit the dense forests that cover the full extent of the nearby rugged Wattagan mountain range. And these monstrous beasts have been known to stray from their mountain homes onto properties on Cessnock's outskirts.
During the last week of December 1975, a Cessnock farmer, tending cattle on his property, caught sight of one of these reptiles moving in scrub nearby his barn. He said it was at least 30 feet in length, was of a mottled greyish colour and stood up to three feet off the ground on four powerfully built legs.
During the previous year of 1974, at least 10 detailed accounts of giant lizard activity reached reporters in Newcastle.
As a cryptozoologist with an interest in all manner of 'unknown' animal reports, I have long been interested in the giant lizards of the Watagan Ranges. However, they are by no means confined to the Wattagans, as we have seen.
What also interests me is the sheer bulk of reports that have come from the north coast and inland New South Wales region-and no wonder, when one considers the vast mountainous regions hereabouts in which they lurk and which could quite easily hide an 'army' of Megalania.
Yet, despite repeated sightings reports, often from quite reputable people, the giant Australian Monitor's existence goes ignored by university herpetologists. "Megalania is extinct!", and that is that!
Mr. Mike Blake does not think Megalania is extinct. During 1974 he was sitting on his farmhouse verandah one day with his utility van parked right in front of his house, situated near bushland outside Cessnock. Suddenly, from around the side of the farmhouse, one of these monstrous beasts walked around in front of his verandah between him and his parked utility.
Mike remained terrified and "glued to his chair", as he said later, while the enormous beast turned and looked at him before moving on leisurely across a nearby paddock toward scrub. Mike compared the lizard's length to his utility which was 18 feet in length. The lizard was at least 20 feet long and stood three feet from the ground.
For as long as residents of the Watagan Mountains have known of these giant lizards, so too have the inhabitants of the Port Macquarie-Wauchope district much further up the coast. Attacks upon cattle by giant goanna monsters are part of local folklore going back into last century.
Queensland Reports
The world-famous Riversleigh fossil beds, situated north of Mount Isa in far north-western Queensland close to the Gulf of Carpenteria, have lately revealed further fossil remains of Megalania together with other remains of giant emus and other 'megafauna' dating from Miocene times.
Before examining the mass of evidence for living Megalania gathered from New South Wales, we shall study some equally astounding reports from Queensland. "Big goannas live in the Kuranda forests," some of the more talkative locals of this little community perched high up on the Atherton Tableland above Cairns, will tell you.
The creatures have left their large tracks across properties on the edge of jungle and taken the odd calf or two, even poultry. Some locals have even sighted these creatures but few talk about these things, no doubt fearing ridicule. Aborigines claim the reptiles wander a wide area of the Cape York and Gulf country forests.
It was while researching on the Atherton Tableland that I met retired Australian Army Major [name witheld] who informed me that when he was about 20 years old, around 1913, he saw a 10-foot-long goanna at Emerald Creek in Queensland.
During the summer of 1963, Mr and Mrs [name witheld] reported seeing a 15 foot-long goanna near Beenleigh, between Brisbane and the Gold Coast, while driving their Renault car on a bush road. "The goanna appeared from out of a gully and dashed across the road into scrub. It stood a good three feet tall on all fours. It was bigger than the nine-foot-wide dirt road we were on," Mrs Karlsen informed me many years later in 1978.
The Karlsen goanna, however, is dwarfed by the following two reports:
Back in August 1981 I was visited by a Queensland soldier, Private Steve" (he did not want his full name published), who related the following incident to me. "During October 1968 I was with my unit on a jungle training exercise deep in forest country, inland from Shoalwater Bay on the Normanby Range north of Rockhampton, when we came upon a dead cow in a remote swampy area.
The cow had been torn apart by some massive beast which, by the cow's appearance, would have been of considerable size and strength to have literally ripped the cow in half the way it had. We found large reptile tracks and tail-marks in the mud about the area of the 'kill'. It now became obvious to us all that the cow had been killed elsewhere, on some pastureland far off, and dragged through the forest to this swamp where it had been devoured. My mates took fright. So did I.
We left the area in some haste. The cow was a fresh 'kill', not even hours old. The 20-inch-or-so width of the claw-marks in the mud, their distance apart, plus the tail-marks, suggested to us that the reptile was up to 30 feet long. We had also examined the drag-marks for some distance through the forest, and the path tramped through the foliage in the opposite direction by the monster perhaps only half an hour before.
If the monster had been up to 30 feet in length, it must have been of considerable weight," said Steve. Perhaps this reptile was a fully grown Megalania, but unless Megalania could grow larger than 30 feet (10 metres), the next reptilian giant might be something else.
1977
One day in 1977, teenage sisters Karen and Susan [name witheld], together with two boys, Alan Johnson and Tom Carrol, were walking along a jungle track in mountain country near Townsville when they saw a huge reptile emerge 100 yards ahead of them from out of dense forest on the edge of a swamp.
"We took fright and hid behind some bushes watching the creature", said Karen to me some years later. "It looked just like a goanna, only it was far, far too big for that. It had a large, goanna-like head, long neck, a huge, almost elephant-like body, enormous legs and big claws, and a long, thick tail. The creature was covered throughout with large scales of a mottled grey colour.
It stood parallel with the swamp, and we estimated its length from head to tail to be a good 40 feet, and its height about six feet tall standing on all fours. We watched as the monster began moving off, trampling foliage as it moved back into the forest. We then got out of there fast. No one believes us to this day, but we know what we saw," she said.
Obviously, if this story is true, the creature was some monstrous goanna, but could it be Megalania, or some other related species?
http://www.mysteriousaustralia.com/australian_giant_reptilian_monsters-qld.html
Northern Territory Reports
In 1978, author Martin McAdoo related to me the experience of friends of his on a dirt road in Arnhem Land, Northern Territory, back in1970.
His mates were in a four-wheel-drive vehicle at the time. As they travelled along the dirt road in a remote area, they were suddenly forced to stop when an enormous goanna appeared on the road ahead of them and rose up on its hind legs a good eight feet from the ground! The creature's tail was about 16 feet long. The reptile then turned and ran off on its hind legs at about 20 miles an hour!
Martin McAdoo learnt at the time that giant monitors of lengths up to and exceeding 20 feet were frequently seen by travellers in remote parts of Arnhem Land and the Gulf country.
One day in early January 1979, Mr Bob Pike, then 25 years old, was driving his four-wheel Land Rover through some rough country near Pindara. He was on a remote dirt track when he saw, emerging from scrub onto the track barely 50 feet ahead of him, a "monstrous lizard' walking upon two powerful pairs of legs, fully four feet off the ground.
"By now I had pulled up, and the reptile eyed me off as it crossed the track a mere 15 feet away from the vehicle. I quickly wound the windows up. Secure inside the vehicle, I watched as the long body and tail passed across the track and into the opposite scrub. I lost no time in driving off. As I did, I could see the reptile vanishing deeper into the bush. I reckon it had a body almost two feet thick and was about 25 feet length in total", he informed me two years later.
Two Aboriginal men reported seeing a 15-foot long lizard in the same area in February that year. Obviously, more than one of these giant-sized monitors existed in that region at that time, and present indications are that others still inhabit the area.
Back in late 1979, Western Australian press and radio publicity about my researches into the giant monitor lizards (or goannas, to give them their Aboriginal designation), resulted in many letters from people over a wide area of the state. Not all these letters concerned reptiles of enormous size, but creatures ranging between 10 and 15 feet in length. Typical was the letter of Mrs Phyllis [last name witheld] [15/11/79]:
Dear Mr Gilroy,
The following incident happened about 47 years ago when I was 10 years of age. I lived with my family on farm situated at Gorge Rock, a small district near Corrigin. Our place was about 11 miles from the town of Corrigin which is in the wheat-belt area.
One day when I was out in the bush, I jumped over a log and nearly jumped on a large reptile I virtually jumped right over it. I got such a fright I ran home and told my parents I had seen what I thought was a type of crocodile. I did not know what else it could have been because it was unlike anything I had seen before, such as the racehorse goanna as we called it..
It appeared to be about 12 feet long, thicker-set like a crocodile, rough skinned and a similar colour to the log. It was apparently resting so I did not see how high it was. I didn't stop around long enough to observe it any more. My parents said I imagined the size, and dismissed my views, but I can still see it in my mind today. Perhaps, with fright, I could have imagined it was larger than it was.
No one ever believed me, and over the years I have mentioned it, but no one ever suggested it could have been one of these monitors. Crocodiles would not be in that dry area. It was not long, and with a thin tail like the racehorse goanna we knew in that area. It was not a little bobtail which we used to pick up and make a pet of.
Yours faithfully,
Mrs Phyllis [last name witheld]
Victorian Reports
Giant reptilian monsters in the Australian bush were known even to our early European settlers and have been discussed around countless outback campfires for generations. Accurate descriptions of them can be found in Aboriginal myths and legends dating back untold thousands of years.
These reptiles have been claimed seen in every mainland Australian state, and are also referred in ancient Tasmanian Aboriginal folklore. Early European settlers claimed to have had numerous encounters with these monsters, and the sighting of one near any bush town was likely to create a wave of terror among the populace.
1890's - 30 Feet in Length
A good example of this can be seen in one famous case which took place during 1890, when a huge reptile, 30 feet in length, instituted a brief reign of terror among the inhabitants of the village of Euroa, Victoria. It tramped its way across properties, leaving behind its gigantic footprints to confirm its awesome size. It was described as a monstrous goanna by those who had happened to see it roaming the bush.
A search party of forty men was formed. Armed with nets and guns, and with cattle dogs to the fore, they ventured off into the surrounding bushland in an attempt to trap the fearsome reptile; but it just disappeared or moved on to another area, never to be seen again in the Euroa district.
Euroa, Victoria 1978
During the first few months of 1978, the town of Mallacoota, situated on the coast just inside the Victorian border with New South Wales, was gripped by 'lizard fever'. A female motorist claimed to have seen a 20 foot-long goanna one afternoon on a road outside the town on the edge of scrub.
This and other claims soon attracted the media, including the Channel 9 network's "A Current Affair" whose journalists, as was to be expected, made light comedy relief of the matter.
One incident the journalists could not make into light entertainment was the case earlier this century of a local man who was said to have been killed and eaten by two of these lizard monsters on a property out of town. Searchers later found what was left of him in nearby scrub.
Euroa, Victoria 1981 -1986
This state has been the scene of a number of more recent giant lizard reports, such as Mr. Ian Hay's 'close encounter' in January 1981.
Mr Hay was rabbit-shooting with a .22 rifle near the town of Bright, situated east of Wangaratta on the Ovens River. As he stood on the river-bank on this particular day, he spotted a large 'log' about 85 yards away further down the river-bank-at least he thought it was a log, greyish-brown in colour. He walked away for a few minutes, but by the time he returned, the 'log' had gone. The 'log' was 15 feet in length.
A young couple told a similar story of what they saw on that same river a few years later in 1986. Across the river they could see, half hidden by grass, a large 'log', but took no further notice of it-that is, until it suddenly rose up and began walking away into dense scrub! They later described the creature as being around 25 feet in length.
What Species?
By now the reader must be wondering what species of monitor lizard we are dealing with. This is a fair question. Certainly they are no ordinary species.
Today, the largest living monitor species accepted by scientists is the notorious Komodo dragon, Varanus komodoensis, found on Komodo Island and one other in the Indonesian chain. But the Komodo dragon is a mere three metres (10 ft) in length, compared to the 6.6, 8.3 and 10-metre lengths (21.5, 27 and 33-ft) given for some giant-sized Australian monitors. Of course there are the occasional over-large Komodo specimens noted, the record length being four metres (13 ft).
Next to the Komodo dragon is the Australian perentie monitor, Varanus giganteus, which, at 2.6 metres (8.5 ft), is claimed to be the second largest monitor in the world. Its distribution is said to be on the western side of the Great Dividing Range. They are not found in Victoria.
Winter of 1979
During the winter of 1979, a 'huge goanna' [as the locals were describing it], mottled greyish skin-coloured and at least 6m (20 ft) in length, was reported seen around the Moruya area, on the New South Wales south coast. A farmer 'John' who found fresh tracks of the monster, embedded in the soil of his recently ploughed field, phoned me and at my request covered them while Heather and I drove down there from Katoomba the next day.
John covered all but one with coatings of grass, the other track he covered with a large bucket. Our hopes of photographing and casting a large number of giant monitor tracks were, unfortunately, largely dashed by heavy rain which fell before our arrival, obliverating all but the specimen beneath the bucket. I was able to prepare a good plaster cast of this track, a five-toed impression measuring 30 cm (11.8 in) in length from middle claw to back of pad, by 31 cm (12.2 in) wide from outstretched left to right claws.
The track was impressed 7 cm (2.7 in) into the soil Sightings of 3 to 6 metre (9.8 to 19.6 ft) length giant goannas continue to be reported from Moruya and other nearby south coastal New South Wales districts.
VARANUS GIGANTEUS: AUSTRALIA'S LARGEST LIZARD
by Eric Pianka at the Section of Integrative Biology, University of Texas at Austin.
The perentie, Varanus giganteus, is Australia's largest species of lizard. These lizards can sometimes exceed eight feet in total length, although the average length is around six feet. They are top predators, eating many other species of vertebrates, including smaller individuals of their own species as well as other species of monitor lizards.
Monitor lizards are large and impressive. They are often the centerpiece of reptile house exhibits. Monitors are not particularly tractable research subjects, but these magnificent lizards have received an extraordinary amount of attention from devoted students. All but one species, the frugivorous Varanus olivaceus of the Philippines (Auffenberg 1988), are active predators that eat quite large prey relative to their own body size. Many monitor lizards are top predators. Some species are aquatic, others terrestrial, while still others are saxicolous and/or semi-arboreal or truly arboreal. Monitor lizards live in a wide variety of habitats, ranging from mangrove swamps to dense forests to savannas to arid deserts.
Currently, 53 extant species are recognized. All occur in Africa, Asia, southeast Asia, and Australia (the new world is sadly impoverished). Some 27 described species are found in Australia, including one lineage that has evolved dwarfism (hatchlings of the smallest species V. brevicauda weigh only one gram). A Pleistocene fossil monitor from Australia (Megalania prisca) is estimated to have reached 16 feet in total length and to have weighed over 1300 pounds. Although monitors are morphologically conservative, they vary in mass by five orders of magnitude. There is proportionately almost as much difference in mass among species of monitor lizards as there is between a mouse and an elephant. No other terrestrial animal genus exhibits such a range of size variation (Pianka 1995).
Sands constitute a natural event recorder, leaving a record of what creatures have moved past. Strong winds regularly dull and erase all tracks. Although it took quite a while, I eventually became fairly skilled at reading the record in the sand. Tracks are difficult to see during mid-day when the sun is high or on overcast days. Morning and afternoon are prime times for tracking when the sun is low in the sky and shadows are long. Tracks are best seen by looking into the light. After a bit of experience, one begins to be able to judge the "run" of the track, that is where the animal is headed. It is almost like becoming the lizard yourself. This allows one to move ahead quickly, cutting the track at intervals, to find the lizard rapidly. You can even tell the approximate age of a track by its crispness and whether or not other tracks, say those of nocturnal species, cross over the track in question. Nothing is much more exciting than finding a crisp new track less than an hour old, for you know that the maker of that track is close by at the end of the track. It is like finding a line guaranteed to lead you to a neat lizard! On a very hot trail I always walk as quietly as possible, barely breathing, scouting ahead to look for the lizard itself. Tracking large lizards across sandy areas has become one of my favorite pastimes. You can learn a great deal about wary unobservable species such as Varanus in this way. It is an incredible thrill when the track suddenly becomes the magnificent animal, captured in mid-stride and frozen in time. More often than not, however, before you see it, the animal breaks into a run and dives down a hole or climbs up a tree and escapes into a hollow. The track of a running animal is often harder to follow than that of one walking.
Statements about Varanus giganteus to follow are based upon impressions I have gained while following literally hundreds of kilometers of giganteus tracks on foot. Individuals usually cover great distances when foraging. I have often followed a fresh track for distances of several kilometers. Tracks indicate little tendency to stay within a delimited area; home ranges of these lizards would appear to be extremely large.
The perentie, Varanus giganteus, attains a total length of more than 6.5 ft. They have been hunted by Aborigines and are exceedingly unapproachable. Their food may once have included small hare wallabies and other mid-sized marsupials, many of which have become extinct. Nowadays, perenties feed on other species of lizards and on introduced European rabbits (several scats examined contained large amounts of hair). An assistant and I flushed the stomach of a medium-sized lizard, which contained a half-digested Varanus gouldi, estimated probable body mass about 14 oz, about 20% of the perentie's overall body mass.
During 207 days in the field in over 16 months in 1966-68, I encountered only two live perenties, one at the edge of sandplain country near a breakaway and the other at a tourist area south of Sandstone, and found no evidence of perentie tracks in the sandy desert. In 1979, I found one perentie, far away from rock outcrops at my sandridge desert site Red Sands. This animal had several deep burrows. A decade later, during 1989-91, perenties were more abundant at Red Sands. I tracked four different individuals, and judged that several others were present by the size of their footprints and lengths of stride. In addition, I saw a dozen other individuals, several in sandy habitats, while driving to and from my study sites. I speculate that perenties have increased in abundance in the Great Victoria desert over the past 25 years, probably in direct response to the increased abundance of introduced European rabbits (Oryctolagus cuniculus). Rabbits were scarce in the Great Victoria desert during 1966-68, were moderately abundant during 1978-79 (pers. obs.), and had become quite common by 1988-93. Perenties could also be expanding their geographic range southwards and eastwards. I have positively identified two very large individuals crossing the road between Menzies and Leonora, one near Lake Goongarrie (30 o 01' S x 121 o 10' E), and the other 28.5 miles South of Leonora.
References
Pianka, E. R. 1982. "Observations on the ecology of Varanus in the Great Victoria desert." Western Australian Naturalist 15: 37-44.
Pianka, E. R. 1986. Ecology and Natural History of Desert Lizards. Analyses of the Ecological Niche and Community Structure. Princeton University Press, Princeton, New Jersey. 208 pp.
Pianka, E. R. 1994. "Comparative Ecology of Varanus in the Great Victoria desert." Australian Journal of Ecology 19: 395-408.
Source: http://uts.cc.utexas.edu/~varanus/giganteus.html
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