Like the diverse environmental conditions, Australia’s animals also come in different shapes and sizes. Some are harmless, while others are dangerous. 

But have you ever wondered what the biggest animal in Australia is?

Growing up to 6 feet, the red kangaroo is the largest terrestrial mammal in the country. On the other hand, Australia’s largest aquatic animal (and overall) is the saltwater crocodile, which can grow to a length of 23 feet.

However, Australia has a few other extra-large animals. From bats that look like flying foxes to giant flightless birds, here are some of the biggest animals in Australia. 

List of 7 Biggest Animals in Australia

According to zoologists, between 200,000 and 300,000 animal species call Australia home. Among all of them, below are 7 of the largest ones.

1. Red Kangaroos
2. Emus
3. Southern Cassowaries
4. Megabats
5. Saltwater Crocodiles
6. Goannas
7. Giant Wrasse

Red Kangaroos 

Max Height: 6 feet (183 cm)
Max Weight: 198 pounds (95 kg)

Native to Australia, the red kangaroo is the largest kangaroo species and marsupial on the planet. Big, healthy males can grow up to 6 feet. 

Males are also the bigger of the sexes and are often referred to as “big heads” by natives. 

The species is sexually dimorphic, meaning males and females exhibit sharp character differences, such as the color of their fur. Males have a reddish-brown coat, and the species is named after this feature. On the other hand, females have bluish-grey fur.

In addition to their impressive height, red kangaroos are strongly built. They are muscular animals that weigh up to 80 kg on average. 

Kangaroos’ strong muscles are mainly concentrated around their hind limbs and tail, appendages used for jumping and balance. Their tails alone can measure up to 3 feet long. 

The need for a tail as long and muscular as this can be observed during altercations; when fighting, red kangaroos deliver powerful kicks with their hind limbs, using their tails to support their weight as they raise their legs in the air to strike. 

Emus

Max Height: 6.2 feet (189 cm)
Max Weight: 121 pounds (55 kg)

The emu is the second largest bird in the world after the ostrich. Still, within its native Australia, the emu is the largest native bird. 

They are flightless birds with long necks and legs, contributing to their average height of 5 to 6 feet. Regarding weight, females are slightly larger, weighing about 55 kg compared to 50 kg for adult males.

In addition, females also have rear ends that are significantly wider than males.

During mating season, around the winter months of December and January, both males and females gain extra weight, with the females remaining slightly bigger. Their eggs are huge with thick shells, typically measuring up to 5 inches and weighing about 500 grams. 

Although emus cannot fly, they have large wings that flap as they run, giving them a bigger appearance in motion. 

Southern Cassowaries

Max Height: 5.9 feet (180 cm)
Max Weight: 167 pounds (76 kg)

Southern cassowaries are native to Australia and some parts of Asia. They are the third tallest birds on the planet after ostriches and emus. 

Like their relatives, cassowaries are flightless black birds with impressive body masses, reaching almost 6 feet in height. 

Cassowaries are distinct-looking birds with a distinctive feature: a horn-like brown casque (an enlarged bone in the skull) that sits atop their heads. The casques measure anywhere from 5-7 inches and contribute to the cassowary’s total length. 

Although emus are taller than cassowaries because of their long necks, cassowaries are the heaviest birds in Australia. 

Female cassowaries can weigh up to 76 kg, while males aren’t known to get past 55 kg. Cassowary eggs are also as large as those of emus, measuring up to 5.4 inches in length. 

Megabats

Max Wingspan: 3.5 feet (107 cm)
Max Weight: 2.2 pounds (1 kg)

The megabat is a native Australian bat species and is the largest in the country. These bats have an average wingspan of 3 feet and can weigh up to 1 kg. From head to claw, megabats measure up to about 11 inches in total. 

Although megabats are also called gray-headed flying foxes, it should be noted that while not all bats are flying foxes, all flying foxes are bats.

The name “flying fox” is simply an exaggeration to point out the bat’s unusual size and should in no way be taken literally. 

Additionally, Australian megabats predominantly rely on sight to locate their food, with a diet primarily consisting of nectar, pollen, and native fruits. Consequently, they have relatively large eyes compared to other bat species. 

Saltwater Crocodiles

Max Length: 23 feet (7 meters)
Max Weight: 2,205 pounds (1,000 kg)

As the biggest living reptiles on the planet, saltwater crocodiles are the largest animals in Australia. A healthy adult male typically weighs about 1,000 kg and can stretch up to 23 feet in length. 

However, females are much smaller, measuring only a meager 8 feet on average compared to males. 

In 1957, a 28-foot-long saltwater crocodile was reportedly caught on the Norman river in Queensland. A cast of it is currently on display as a famous tourist attraction.

As apex predators and the strongest reptiles, Australia’s saltwater crocodiles are the living dinosaurs who rule their habitat. They are hypercarnivores that aggressively tackle anything that strays into their territory until it becomes food.

With a size like that, it is relatively easy for the crocodiles to win every wrestling match. They catch their prey using their massive jaws, and to make the job quicker, they drag it back into the water to drown it. 

Saltwater crocodiles’ jaws are so powerful they exert over 2,000 kg of force in a single bite. For scale, the average human can only manage 45 kg. 

Goannas

Max Length: 8 feet (240 cm)
Max Weight: 44 pounds (20 kg)

As predatory monitor lizards, goannas are naturally equipped with sharp teeth and claws. The largest species is called the perentie, or giant goanna. 

Goannas can grow as long as 8 feet, making them the biggest monitor lizard in Australia and among the biggest on the planet. Although perentie goannas are typically lean lizards, they weigh up to 15 kg on average and about 20 kg in certain instances.

Perenties are excellent diggers and climbers. In case of a threat, they can quickly burrow into the ground or climb trees with their sharp claws. 

However, if cornered, perenties will stand their ground, using their razor-sharp teeth and claws to inflict significant damage. 

Scientists also speculate that all monitor lizards, including goannas, may be venomous. If this is indeed the case, it means the perentie has extra ammunition in its arsenal. 

Giant Wrasse

Max Length: 6 feet (183 cm)
Max Weight: 420 pounds (190 kg)

Veering away from terrestrial and semi-terrestrial animals, let us dive into Australia’s Great Barrier Reef. Of particular interest to our article is the giant wrasse – one of the heaviest and biggest animals in Australia.

Giant wrasses are enormous fish weighing up to 190 kg and growing as long as 6 feet. However, females only reach about 3 feet, only half the size of males. 

Apart from their iconic forehead bumps and colossal size, giant wrasses are also notable for their beauty. 

With diamond patterning, vibrant shades of purple, green, blue, and yellow scales, and noticeable “eyelashes,” giant wrasses are popular with tourists. They are often featured in tourist media, like Australia’s famous Wally the wrasse.