It looks like a duck 's bill, but is actually quite soft and covered with thousands of receptors that help the platypus detect prey. Males are also venomous. They have sharp stingers on the heels of their rear feet and can use them to deliver a strong toxic blow to any foe.
These mammals are bottom feeders. They scoop up insects and larvae, shellfish, and worms in their bill along with bits of gravel and mud from the bottom. All this material is stored in cheek pouches and, at the surface, mashed for consumption. In the south, mating is about a month later. After mating, the female eats a lot of food and builds a nesting burrow.
Experts have found that the nursing burrow can be up to 30 m long. She blocks herself into the burrow with dirt to protect herself from floodwater and predators. Blocking the burrow also helps to keep the nesting chamber at an even temperature and humidity for incubation.
After laying two sticky, soft-shelled eggs, the female curls up to incubate the eggs by holding them to her belly with her tail. Incubation for the 17 mm eggs takes about one to two weeks. Tiny young are born naked, blind and with undeveloped limbs.
After birth, the baby drags itself to its mother's belly, where it suckles on mammary patches where milk oozes onto the skin. The young stay in the burrow for weaning, while the mother leaves to forage. After about five weeks, the mother spends more time away from her young. At four months, the young venture out of the burrow and are fully grown by the time they're one year old.
If you want to see a platypus in the wild, find a creek or still pool where platypus are known to live. The best times to see a platypus are dusk or early morning. Platypus have sensitive hearing and are easily disturbed. Sit quietly and watch the water surface for ripples which usually show a platypus is present.
Look for a conspicuous bow wave caused by front feet while paddling. After mating, a pregnant female builds a nest in a long complex burrow possibly re-worked by several females in different seasons in less than a week.
She spends further days collecting wet nesting material to prevent her eggs and hatchlings from drying out. During the egg incubation period, a female holds the eggs pressed by her tail to her belly, while curled up. The female spends most of this time with her young in the burrow, and as the young grow, she increasingly leaves them to forage.
Towards the end of the summer the young emerge from the burrow and their fate as young independent animals is still largely unknown. The Platypus is protected by legislation in all of the states that it occurs in. Individuals cannot be captured or killed, except for scientific research. The Platypus is a common species with very little apparent change in its historical distribution except in South Australia.
However, there is a general lack of knowledge in the species abundance at local catchment levels to predict population trends. The dependence of Platypuses on the established freshwater systems may lead to their decline in future.
Platypuses spend most of their time in water or their burrow, so it is difficult to determine their predators. There have been anecdotal reports of the species being predated on by crocodiles, goannas, carpet pythons, eagles and large native fish. In addition, it is likely that foxes, and possibly dogs or dingoes kill Platypuses that move on land or in shallow waters.
Platypuses have a number of ectoparasites in the wild, including their own tick species, Ixodes ornithothynchi. The tick is often found around the hind limbs, and in smaller numbers on the front legs and in the body fur. Severe skin ulcers caused by the amphibian fungal infection have been reported in Tasmanian Platypuses in particular. The fungus can be fatal to the animal if it invades other tissues, particularly the lungs. Male Platypuses have a calcaneous, sharp spur about 12 millimetres long on each ankle.
The spur is connected via a long duct to a gland that produces venom, particularly in the breeding season. The venom can cause severe pain to humans, and although not lethal, the pain caused has been described as excruciating. Swelling rapidly develops around the wound and gradually spreads throughout the affected limb.
Information obtained from case histories and anecdotal evidence indicates that the pain develops into a long-lasting hyperalgesia temporary increased sensitivity to pain that persists for days or even months. Therefore, if there is a need to handle a Platypus helping an injured animal for instance , it should always be picked up by the end half of the tail to avoid the spur in case it is a male.
The fossil record for monotremes is poor in comparison to that of other groups of mammals, and until recently little was known about their evolutionary history. Several fossil discoveries since the early s have shed some light on the origins of monotremes. We now know that monotremes were present in Australia during the Mesozoic Era, when Australia was still part of the supercontinent, Gondwana. Four species related to Platypus have been found in fossil deposits from Australia, including a complete skull of Obdurodon dicksoni and an opalised jaw fragment of Steropodon galmani.
The latter is million years old and represents one of Australia's oldest mammals. The only evidence that Platypus ancestors were once present outside Australia came in , when a million year old fossil tooth was found in Patagonia, in southern Argentina.
Studies of these fossils indicate that the one remaining living species of Platypus is more specialised than its predecessors. It is smaller, its functional teeth have been replaced by horny pads and other aspects of its anatomy appear simpler. The watertight nostrils on its bill remain sealed so that the animal can stay submerged for up to two minutes as it forages for food. The bill also comes equipped with specialized nerve endings, called electroreceptors, which detect tiny electrical currents generated by the muscular contractions of prey.
It has no teeth, so the platypus stores its "catch" in its cheek pouches, returns to the surface, mashes up its meal with the help of gravel bits hoovered up enroute, then swallows it all down.
Baby platypuses hatch after 10 days and nurse for up to four months before they swim off and forage on their own.
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