The Australian water dragon (''Intellagama lesueurii''),
which includes the eastern water dragon (''Intellagama lesueurii lesueurii'' ) and the Gippsland water dragon (''Intellagama lesueurii howittii'' )
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
, is an
arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
agamid
Agamidae is a family of over 300 species of iguanian lizards indigenous to Africa, Asia, Australia, and a few in Southern Europe. Many species are commonly called dragons or dragon lizards.
Overview
Phylogenetically, they may be sister to the I ...
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
native to eastern
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
from
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
northwards to
Queensland
)
, nickname = Sunshine State
, image_map = Queensland in Australia.svg
, map_caption = Location of Queensland in Australia
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, established_ ...
. There may be a small introduced population on the south-east coast of
South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
.
Etymology
The
specific name, ''lesueurii'', is in honor of French
naturalist Charles Alexandre Lesueur
Charles Alexandre Lesueur (1 January 1778 in Le Havre – 12 December 1846 in Le Havre) was a French Natural history, naturalist, artist, and explorer. He was a prolific natural-history collector, gathering many type specimens in Australia, ...
.
Description
Australian water dragons have long powerful limbs and claws for climbing, a long muscular laterally-compressed tail for swimming, and prominent
nuchal
The nape is the back of the neck. In technical anatomical/medical terminology, the nape is also called the nucha (from the Medieval Latin rendering of the Arabic , "spinal marrow"). The corresponding adjective is ''nuchal'', as in the term ''nu ...
and vertebral crests.
(A nuchal crest is a central row of spikes at the base of the head. These spikes continue down the spine, getting smaller as they reach the base of the tail.)
[Australian National Botanic Gardens: Research into Water Dragons]
Including their tails, which comprise about two-thirds of their total length, adult females grow to about 60 cm (2 feet) long, and adult males can grow slightly longer than one metre (39 inches) and weigh about 1 kg. Males show bolder colouration and have larger heads than females.
Colour is less distinct in juveniles.
Species variation
The Australian water
dragon
A dragon is a reptilian legendary creature that appears in the folklore of many cultures worldwide. Beliefs about dragons vary considerably through regions, but dragons in western cultures since the High Middle Ages have often been depicted as ...
is the only
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of the genus ''Intellagama''.
[
There are two ]subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
; ''Intellagama lesueurii lesueurii'' (eastern water dragon) and ''Intellagama lesueurii howitti'' (Gippsland
Gippsland is a rural region that makes up the southeastern part of Victoria, Australia, mostly comprising the coastal plains to the rainward (southern) side of the Victorian Alps (the southernmost section of the Great Dividing Range). It covers ...
water dragon). ''Intellagama lesueurii lesueurii'' tends towards white, yellow and red on the throat and possesses a dark band behind its eye; ''Intelligama lesueurii howitti'' lacks this and instead has dark bands on either side of its throat, which is blotched with yellow, orange, or blue. Both subspecies are light greenish grey in overall colour with black bands running across their back, tail and legs. The water dragon can slowly change skin colour to aid its camouflage. The skin will shed during periods of growth.
Behaviour
Australian water dragons are extremely shy in the wild, but readily adapt to continual human presence in suburban parks and gardens. They are fast runners and strong climbers. When faced with a potential predator, they seek cover in thick vegetation, or drop from an overhanging branch into water. They are able to swim totally submerged, and rest on the bottom of shallow creeks or lakes for up to 90 minutes,[ to avoid detection.
Both males and females display typical ]agamid
Agamidae is a family of over 300 species of iguanian lizards indigenous to Africa, Asia, Australia, and a few in Southern Europe. Many species are commonly called dragons or dragon lizards.
Overview
Phylogenetically, they may be sister to the I ...
behaviour such as basking, arm-waving and head-bobbing. Fast arm-waving signals dominance, while slow arm-waving signals submission. Males are territorial,[ and in areas of higher population density, males exhibit displays of aggression toward other males including posturing, chasing and fighting.
]
Breeding
Australian water dragons living in cooler Australian climates
Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologic ...
hibernate
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...
over winter. During spring, usually in early October, the female
Female (Venus symbol, symbol: ♀) is the sex of an organism that produces the large non-motile ovum, ova (egg cells), the type of gamete (sex cell) that fuses with the Sperm, male gamete during sexual reproduction.
A female has larger gamet ...
excavates a burrow about deep and lays between 6 and 18 eggs.[ The nest is usually in sandy or soft ]soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...
, in an area open to sun. When the mother has laid the eggs, she backfills the chamber with soil and scatters loose debris over it. Australian water dragons exhibit temperature dependent sex
Sex is the trait that determines whether a sexually reproducing animal or plant produces male or female gametes. Male plants and animals produce smaller mobile gametes (spermatozoa, sperm, pollen), while females produce larger ones (ova, oft ...
determination; the sex of the hatchlings
In oviparous biology, a hatchling is a newly hatched fish, amphibian, reptile, or bird. A group of mammals called monotremes lay eggs, and their young are hatchlings as well.
Fish
Fish hatchlings generally do not receive parental care, similar to ...
is determined by the temperature of the nest site.[
When the young are born they stay near the entrance of the burrow for some time before leaving home. When they finally leave the nest, they tend to group together away from the adult population.]
Habitat
As its name suggests, the Australian water dragon is associated with water and is semi-aquatic. It can be found near creeks, rivers, lakes, and other water bodies that have basking sites such as overhanging branches or rocks in open or filtered sun. The species is very common in the rainforest section of Brisbane Botanic Gardens, Mount Coot-tha
The Brisbane Botanic Gardens (formerly the Mount Coot-tha Botanic Gardens and informally the Toowong Botanic Gardens) are located from the Brisbane CBD at the foot of Brisbane's tallest mountain, Mount Coot-tha in the suburb of Mount Coot-th ...
in Queensland, and a monument has been built to them there.
There are anecdotal reports of a small colony living on the Sixth Creek in the Forest Range
A forest range is a term used to define administrative regions containing one or more (usually) demarcated and (usually) protected or resource-managed forests. The term was in use in British India, and hence India, Pakistan and Bangladesh use thi ...
area of South Australia, hundreds of kilometers outside their natural range, which were probably introduced there during the 1980s by a local reptile enthusiast.
Predators, threats and diet
Australian water dragons are prey to carnivorous birds, snakes, cats, dogs, and foxes. Nestlings and smaller juvenile water dragons are vulnerable to predation by kookaburra
Kookaburras are terrestrial tree kingfishers of the genus ''Dacelo'' native to Australia and New Guinea, which grow to between in length and weigh around . The name is a loanword from Wiradjuri ''guuguubarra'', onomatopoeic of its call. The ...
s, currawong
Currawongs are three species of medium-sized passerine birds belonging to the genus ''Strepera'' in the family Artamidae native to Australia. These are the grey currawong (''Strepera versicolor''), pied currawong (''S. graculina''), and black cu ...
s, butcherbirds and other carnivorous birds.[Australian National Botanic Gardens: Predators of Water Dragons]
They are also prone to becoming road kill due to the attraction of warm bitumen and concrete for basking.[
The Australian water dragon's diet depends on its size. Juveniles and yearlings tend to feed on spiders and small insects such as ants, crickets, and caterpillars. When they get bigger, so does their prey. An adult diet includes small rodents, such as baby mice, other reptiles, frogs, fish, crabs, yabbies, molluscs, worms and eggs, although insects are still the most commonly consumed. Types of vegetation reportedly consumed include figs, lilly-pilly fruits, berries, and other fruits and flowers.]
Gallery
File:Physignathus lesueurii paulbrian.jpg, Australian water dragon, Brisbane
Brisbane ( ) is the capital and most populous city of the states and territories of Australia, Australian state of Queensland, and the list of cities in Australia by population, third-most populous city in Australia and Oceania, with a populati ...
File:Water Dragon 001.jpg, ''Intellagama lesueurii lesueurii'' (eastern water dragon) at Kirra, Queensland
File:1A B-DRAGON.JPG, ''Intellagama lesueurii lesueurii'' (eastern water dragon)
File:Gippsland-Water-Dragon---Physignathus-lesueurii-howittii.jpg, Swimming across river in Melbourne
File:Eastern Water Dragon Clontarf.jpg, Head detail of the eastern subspecies
File:Physignathus lesueurii lesueurii (Sydney, 2010-03-24).jpg, ''Intellagama lesueurii lesueurii'' (eastern water dragon) basking on a log in suburban Sydney
Sydney ( ) is the capital city of the state of New South Wales, and the most populous city in both Australia and Oceania. Located on Australia's east coast, the metropolis surrounds Sydney Harbour and extends about towards the Blue Mountain ...
File:Eastern water dragon.jpg, ''Intellagama lesueurii lesueurii'' swimming, Shoalhaven River
The Shoalhaven River is a perennial river that rises from the Southern Tablelands and flows into an open mature wave dominated barrier estuary near Nowra on the South Coast of New South Wales, Australia.
Location and features
The Shoalhaven ...
, New South Wales
)
, nickname =
, image_map = New South Wales in Australia.svg
, map_caption = Location of New South Wales in AustraliaCoordinates:
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, es ...
File:Water Dragon Sydney Harbour.JPG, Australian water dragon surveying Sydney Harbour
Port Jackson, consisting of the waters of Sydney Harbour, Middle Harbour, North Harbour and the Lane Cove and Parramatta Rivers, is the ria or natural harbour of Sydney, New South Wales, Australia. The harbour is an inlet of the Tasman Sea (p ...
File:1523239 10152141733016206 1259332200 o.jpg, Eastern water dragon at Brisbane Botanic Gardens
File:857853 10152141732796206 1865575802 o.jpg, Eastern water dragon at Brisbane Botanic Gardens
File:Eastern Water Dragon 20140125.jpg, Juvenile eastern water dragon in Roma Street Parkland
Roma Street Parkland covers 11 hectares in the centre of the City of Brisbane, Queensland, Australia. The Roma Street Parkland is adjacent to Brisbane Transit Centre and the Roma Street railway station from which it takes its name (the park ...
, Brisbane, Queensland, Australia
File:AndrewMercerIMG 5618 Australian Water Dragon.jpg, Eastern water dragon in Brisbane Botanical Gardens
File:AndrewMercerIMG 5585 Australian Water Dragon.jpg, Head of an eastern water dragon poking out of a pond in Brisbane Botanical Gardens
File:Male Eastern Water Dragons Fighting (IMG8022).jpg, Two male Australian eastern water dragons (''Intellagama lesueurii lesueurii'' ) fighting.
File:Australian Eastern Water Dragon basking in the sun at Blue Mountains NSW Australia.jpg, Australian eastern water dragon basking in the sun at Blue Mountains (New South Wales)
The Blue Mountains are a mountainous region and a mountain range located in New South Wales, Australia. The region borders on Sydney's metropolitan area, its foothills starting about west of centre of the state capital, close to Penrith o ...
File:Intellagama Lesueurii with Red Spots - AndrewMercer - DSC10821.jpg, A Dragon that has been marked for research purposes.
File:Adult male Australian Eastern Water Dragon in a tree.jpg, alt=, Adult male Australian Eastern Water Dragon in a tree overhanging a creek in suburban Brisbane
References
Further reading
* Boulenger GA. 1885. ''Catalogue of the Lizards in the British Museum (Natural History). Second Edition. Volume I. ... Agamidæ ...'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xii + 436 pp. + Plates I-XXXII. (''Physignathus lesueurii'', pp. 398–399).
External links
Video of male Gippsland Water Dragons fighting on Youtube
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{{Taxonbar, from=Q738712
Agamidae
Agamid lizards of Australia
Reptiles described in 1831
Taxa named by John Edward Gray