Platypus

The platypus, or duck-billed platypus (Ornithorhynchus anatinus) is a unique Australian monotreme. A monotreme is a type of mammal that lays eggs. Platypus and echidnas are the only monotremes in the world.

Appearance
The platypus can grow up to 60cm long. With a broad, dark brown duck-like bill, long flat body and wide tail, it moves easily through water. Platypuses’ bills are covered by dark grey skin and have thousands of special sensory receptors that help it detect movement underwater.

Its body is covered in thick waterproof fur that is dark brown on the back and light brown or creamy on the belly. It has short legs with sharp curved claws that are covered with webbing to help it swim. The male platypus has venomous spurs on its back legs.

Distribution and habitat
The platypus is widespread along the east of Australia, from Queensland to Tasmania. It is found in almost all areas of Victoria except the Mallee. Platypus live in freshwater creeks, streams, rivers, and lakes. Some even live in the Yarra River in Melbourne and in other creeks and streams surrounding the city. Platypus prefer water that has lots of twigs, roots, gravel, and logs, as this increases its food sources. It digs burrows under trees, shrubs, and roots along the banks of water sources.

Diet
The platypuses’ diet is mostly made up of aquatic insects. It will also eat worms, small fish, shrimp, and freshwater molluscs. The platypus uses its bills to find food along the gravel, rocks and sticks on the bottom of creeks and streams. It stores the food it finds in cheek pouches and then returns to the surface to eat. Instead of teeth, the platypus has hard plates that it uses to grind its food.

Behaviour
Platypuses are very shy and elusive animals. It usually feeds at night for up to 10 to 12 hours, then returns to rest in its burrow during the day. When it forages, it dives down to the bottom of the water and can hold its breath for up to 11 minutes!

When it’s not foraging, the platypus rests in burrows in banks, under tree roots, or in logs near waterways. These burrows can have entrances both above and below water level.

Breeding season
The platypus breeding season in Victoria is between August and October. Platypuses have been seen performing courtship activities, such as diving, touching, and rolling through the water together. The male will grasp the females tail in its bill.

The female platypus builds a complex nesting burrow that can be over 10m long. It keeps the eggs warm in the burrow by holding them between its curled-up tail and its belly. After hatching, platypus young live in the nesting burrow for three months before first entering the water. During this time, they feed on milk from their mother that is secreted from two special patches of skin on their bellies.

General fun facts

  • Platypus eat between 20% and 50% of their body weight in food each day.
  • Flaps of skin cover platypus’ eyes, ears and nose when it swims underwater. It uses electroreceptors on its bill to detect movement from prey underwater.
  • The platypus stores up to 30 to 60% of its body fat in its tail.
  • The venomous spikes on the males’ feet make the platypus one of very few venomous mammals in the world.

Common threats to platypus

If you see a sick, injured or orphaned platypus do not attempt to touch it or pick it up. Male platypus have sharp venomous spikes on their hind feet, which can cause excruciating pain to humans. If you see a sick, injured or orphaned platypus, call Wildlife Victoria’s Emergency Response Service on (03) 8400 7300 for advice or assistance.

Litter
Platypus can be injured by rubbish in waterways. Metal, plastic and rubber rings can get caught around platypuses necks, and broken glass can cut its bill. Make sure to put your rubbish in a bin and safely clean up any rubbish you see around waterways.

Nets
Opera house nets are illegal in Victorian public waters, as they can trap and kill platypus, turtles and water rats. If you are going yabbying in Victoria, use a hoop net instead to reduce the risk to our precious native wildlife.

Predators
Introduced animals such as foxes, dogs and cats can severely injure platypuses. Keep dogs on a leash near known platypus locations.