When swimming, the platypus moves itself with its front feet and uses its back feet for steering and as brakes. Water doesn't get into the platypus's thick fur, and it swims with its eyes, ears and nostrils shut. In Queensland, platypus mate in August. 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. They thought that a trickster had sewn two animals together, according to the BBC. Platypuses are among the few venomous mammals.
Males have a spur on the back of their hind feet that is connected to a venom-secreting gland. More venom is secreted during mating season, leading researchers to think that the spurs and venom help males compete for mates, according to the Australian Platypus Conservatory. The venom is not life threatening to humans, but it can cause severe swelling and "excruciating pain. A typical platypus is 15 inches 38 centimeters from its head to the end of its rump.
Its tail adds an additional 5 inches 13 cm to the animal's length. An individual weighs about 3 lbs. Scientists have found fossils that suggest that ancient platypuses where twice as large as the modern variety, at 3. Platypuses have dense, thick fur that helps them stay warm underwater. Most of the fur is dark brown, except for a patch of lighter fur near each eye, and lighter-colored fur on the underside.
Their front feet have extra skin that acts like a paddle when the animals are swimming. When platypuses are on land, their webbing retracts, making the claws more pronounced.
The animals walk awkwardly on their knuckles to protect the webbing. These characteristics coupled with the absence of visible ears distinguish the Platypus from the dog-paddle style of the Water-rat.
Platypuses can swim through fast waters at the speed of around 1 metre per second, but when foraging the speed is closer to 0. However, the Platpus is not well adapted for walking on land. The Platypus is largely a solitary animal, but several individuals can share the same body of water.
The vocalisation has not been recorded in the wild, but captive animals produce a low-pitched growling sounds when disturbed or handled. Young Platypuses do not seem to reproduce in their first year of life, instead, both sexes become reproductive in their second year. Still, many females do not breed until they are at least 4 years old. After mating, a female will lay eggs usually 2 following a days gestation period. She then incubates the eggs for possibly 10 days, after which the lactation period lasts for months before the young emerge from the burrow.
Platypuses are long-lived animals both in captivity and in the wild, living up to approximately 20 years. The breeding season of the Platypus varies with distribution and within populations.
Mating normally takes place between August to October in New South Wales and Victoria, and lactating females were observed between September and March. The knowledge of the breeding behaviour generally comes from observations of animals in captivity. In winter when the water is still cold males initiate mating interactions.
The behaviour last from less than a minute to over half an hour and is usually repeated over several days.
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. When water-rats are dry and seen at close range, their fur may depending on the area be chocolate brown, reddish brown, mouse grey or even mottled grey-brown, with underparts that vary in colour from cream to light brown to golden yellow.
Both species typically float low in the water, with just the top of the head and back and sometimes a bit of tail visible as they swim on the surface. A platypus seen from a distance of about 25 metres above and a water-rat seen from a distance of about 15 metres below. Platypus and water-rats are also quite similar in size, with very large adult males of both species measuring up to about 60 centimetres in length including the tail.
Juveniles are of course smaller than most adults when they first enter the water. Juvenile platypus first emerge from nesting burrows in late January to early March in Victoria and New South Wales, with Queensland juveniles emerging a few weeks earlier and Tasmanian juveniles up to around two months later.
By comparison, young water-rats are seen over a much longer period of time, from early spring to at least early autumn. The best way to distinguish a water-rat from a platypus in the water is to look carefully at the tail: the water-rat has a long, narrow tail with a conspicuous white tip, whereas the platypus has a flat, uniformly dark, paddle-like tail. Platypus are also very rarely seen on land, though they may occasionally rest on a log or rock, usually while grooming. In contrast, water-rats are much more likely to be seen on land, either consuming their prey or running along the bank as shown above.
The platypus diet mainly consists of aquatic insects such as mayfly and caddis-fly larvae, along with other invertebrates such as worms, freshwater shrimps and yabbies. Prey items are stored in cheek pouches and then chewed up and swallowed after a platypus returns to the surface to breathe as shown below. In contrast to a platypus, a water-rat is equipped with a sharp set of teeth and front paws that are good at grasping and holding things. Hence, while water-rats eat some of the same insects and other items regularly eaten by a platypus, they also dine on fish, large mussels and crabs, frogs including cane toads and occasionally even waterfowl such as ducks.
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