Ornithorhynchus anatinus

Along with the kangaroos, the Platypus is totally identified with Australia. It is an animal which suckles it young, has fur, but also has a bill like a duck and it lays eggs. Not surprisingly with such an unusual animal, legends and myths about it abound.

It is a beautiful, secretive and shy creature.

The Platypus (Ornithorhynchus means 'birdlike snout' ) is streamlined like other mammals which live in water, such as otters and beavers, but it is much smaller than these animals. It is roughly half the size of an average household cat.

It is seldom seen except when resting at the water surface. It can be identified by its duck-like beak, domed head, white fur around the eyes, outspread limbs and broad, flattened tail. It has a covering of dense waterproof fur over all of its body except for its feet and bill. The outer hair is dark brown on its back and yellowish on its underside. Behind the beak (or bill as it is called) are two grooves which house the ear openings and the eyes, both of which are closed while the animal dives.

The tail of the platypus is mainly made up of a fatty tissue that is used to store energy supplies which the animal can use when there is a shortage of food, such as in the winter months.

Its webbed feet could be the reason why the platypus is called a platypus because the webbed feet give the impression that the platypus is flat-footed, which is what platypus means.

One of three living species of egg-laying mammals (order Monotremata), it is amphibious and it swims with its webbed forefeet while using its webbed hindfeet to steer or to brake.


An underwater view


When the Platypus is walking or digging, the webs of the fore feet fold back to expose broad nails. Each rear leg in the male also bears a horny spur on the ankle, about 1.5 cm in length, which is attached by a duct to a poison gland in the thigh area. This gland produces venom, particularly in the breeding season. The platypus is the only Australian mammal known to be venomous. Its venom is not considered to be life-threatening to a healthy human. However, spurring is painful - in part, because platypus spurs are sharp and can be driven in with great force. As well, platypus poison triggers severe pain in the affected limb and can result in quite spectacular localised swelling.

The Platypus is a warm-blooded mammal which lays and hatches eggs. A female platypus produces a clutch of one to three eggs in late winter or spring. The eggs are 15-18 millimetres long and have a thin, leathery shell, like those of snakes and lizards. The mother is believed to incubate them between her lower belly and curled-up tail for a period of about 10 or 11 days as she rests in an underground nest made of leaves or other vegetation collected from the water.

A female platypus does not have nipples. Instead, a rich milk is secreted from two round patches of skin midway along the mother's belly. It is believed that a baby platypus feeds by slurping up milk with rhythmic sweeps of its stubby bill. When the juveniles first enter the water at the age of about four months, they are nearly (80-90%) as long as an adult.

Male platypus do not help to raise the young.

It eats caddis-fly larvae and mayfly larvae and a few other tpes of river bottom-dwelling invertebrate animals such as adult horsehair worms and shrimps, even small snails and pea-shell mussels in some cases.

Fossil evidence shows that a type of platypus may have been present in Australia as long ago as 110 million years (during the geological Cretaceous Period). Ornithorhynchus anatinus has been part of the Australian fauna for at least 50,000 years, occupying the rivers of the Australian mainland and Tasmania, in an area ranging from Cooktown in Queensland - along the eastern coast of Australia- down to Melbourne and King Island, and Hobart. It is much more common in the Southern parts of Australia than it is in the Northern parts. This could be due to two factors, these being the presence of crocodiles in the North and a greater threat from flooding.

Platypuses were severely reduced in numbers during the 19th century when they were being killed for their fur, and some simply 'for sport.' Many of these animals were turned into slippers and apparel for women. Fortunately for the Platypus, though, its fur was not particularly valued as an export item because its thick skin made it very difficult to work into garments. Even more fortunate was its protection in all Australian states around the turn of the century.


Looking down on a Platypus from a bridge



Tommy Grant, The Platypus: A Unique Animal, with illustrations by Dominic Fanning, UNSW Press, 1995.

Barbara Triggs, Tracks, Scats and Other Traces: A Field Guide to Australian Mammals, Oxford University Press, Melbourne, 1996.

Ronald Strahan, A Photographic Guide to Mammals of Australia, The Australian Museum and New Holland Publishers, Ltd., 1995.

The Complete Platypus,

Australian Platyus Conservancy,

Australian Fauna: The Platypus,



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