Cassowary vs Ostrich

2 big birds ostrich and Cassowary

Amazing birds too!

Now if you are wondering – Cassowary vs Ostrich – who would win?

In short the answer is..

While both cassowaries and ostriches are flightless birds with strong muscular legs.  However, an ostrich is faster, bulkier, and even taller than an average cassowary. And yet, cassowaries are better equipped for fighting owing to their razor-sharp toenails and territorial aggression.

This article is not just going to talk about who would win but also the difference between the two birds

Also, why are Cassowary the most dangerous birds?

What’s the story behind this?

You’ll discover this in the article

Before predicting who shall win, let’s start with what we know, say:

Which Is Bigger Ostrich Or Cassowary?

Ostriches are the biggest living birds on earth. 

Adult ostriches weigh about 133 kgs and can grow up to 9 feet tall.

Compared to this, an average cassowary weighs only about 57 kgs and can grow up to 6.6 feet

However, cassowaries are considered the third tallest birds of the world, with emus being the second.

Despite that, cassowaries outweigh most emus as an average emu is only about 50 kgs.

The massiveness of these birds may vary even among species:

1. Cassowary Species

There are three living cassowaries:

  1. Southern Cassowary (Casuarius casuarius) is the biggest cassowary weighing about 70kgs and exceeding 6 feet in height. These have double red wattles and occupy lowland eucalyptus forests or swamps.
  2. Northern Cassowary (Casuarius unappendiculatus) are single-wattled cassowaries that live in the rainforests of Northern Guinea. These grow about 5 feet 10 inches tall and weigh around 37 kgs.
  3. Dwarf Cassowary (Casuarius bennetti) is also called “Mooruk” (Mountain Cassowary) as it resides at high altitudes of about 3.3Km. These weigh only about 18 kgs and grow about 4 feet tall. 

2. Ostrich Species

These include:

  1. Common Ostriches (Struthio camelus) are typically 150kgs and 9 feet tall.
  2. Somali Ostriches (Struthio molybdophanes) are similar to a common ostrich in size but differ genetically.

But size is not the only winning factor.

And so, a more appropriate question may be:

What Is The Difference Between An Ostrich And a Cassowary?

While ostriches and cassowaries seem like close relatives, they are not.

In the taxonomic classification, the two birds don’t even share the same Order (depicted by figure).

And so, their only similarity lies with both being birds. 

Cassowary vs Ostrich

1.Differences In Appearance:

Cassowary Ostrich
General appearance Relatives of dinosaur-birds or “Ratites”. But, they look like an over-grown turkey.

Vivid blue bodies, red wattles, keratin-covered hollow bony crests on the head called “casque”.

Resembles a camel with a long neck and jolting walk, therefore, called “The camel bird”.

Color ranges from white to pink, bare heads and necks but feather-covered bodies. 

Size 2nd only to ostrich (max. 70 kgs and 6 feet 5 inches tall). The biggest birds in the world (max 155 kgs and 9 feet).
Beak Sharp without teeth. Sharp teeth within the beak.
Legs, Feet, and Talons 3 toes with innermost toe having 12cm long razor-sharp toenail.

Scaly muscular legs, can jump to 5 feet and run about 50 km/hour.

Have only 2 toes but developed into a hoof-like shape. Have a 10cm long rounded talon.

Scaly muscular legs, can jump to 7 feet high and run up to 75km/hour.

Eyes Regular-sized eyes. Biggest eyes among land animals with a 2-inch diameter. They can see danger approaching from miles.
Voice Deep roar to claim territory. Only males produce booming calls.
Eggs 3-8 green or greenish-blue eggs per clutch.

Each egg is 9 by 14 cm.

12-18 white to pale yellow eggs per clutch.

Each egg is 13 by 15cm (The largest eggs in the world). 

Gender Differentiation Similar in appearance but females weigh about 80 kg and males 55kg. Males are taller with bold black plumage, while females are smaller and white to light brown.

2. Differences In Habitat Preferences

Cassowary Ostrich
Ideal Habitat Prefer forest swamps & palm scrubs. 

Native to northern Australia, New Guinea, and surrounding rainforests.

Prefer open arid areas as vegetation obstructs their escape. 

Can survive without water for days and endure high temperatures. 

Found mostly in Africa, farmed in Mexico.

Nests Consists of a heap of leaves. Shallow land pits.

3. Differences In Behaviors And Organ Systems

Cassowary Ostrich
Social Behaviors Mostly live alone in loose territories and leave only to find a mate during the breeding season.

Shy birds but can be aggressive if provoked.

Mostly live as groups of 5 but during the breeding season may live like a flock of 5-50 ostriches

Territories are 2-15 Km2.

Aggressive if provoked.

Foraging and Prey Consume about 5kg of fruit a day. Also eat insects, snails, fungi, and carrion. 

Can catch fish by spreading wings like a net.

Eat plants especially roots, leaves, and seeds. Can munch insects, rodents, lizards, and even snakes.
Breeding Patterns Couples stay together for about 1 month, the female flees after laying eggs. While the male incubates the eggs for 50 days and raises them as a single parent for about 9 months.  Polygamous but mate for life, dominant male ostriches have a harem of 3-5 females with one alpha female.
Hatchlings Follow the males Stay under the shadow of females.
Digestive system Swallow the whole fruits but lack a gizzard. So, dung consists of large undigested seeds that germinate easily into plants. The food stays in the crop until the lump is big enough to slide through the neck. Can eat 2.2 pounds of sand, pebbles, or stones to grind the food within gizzards.
Urinary Tracts No separate urinary tract. The only birds with separate systems for defecation and urination. 
Reproductive System Though non-functional, both genders have male and female reproductive organs. While females only have a cloaca, the males have discrete reproductive organs.

Now you may have questions like:

Are Cassowaries More Dangerous Than Ostriches?

That depends on context.

Well, a cassowary is more likely to run from you than an ostrich.

People around the globe have even used ostriches in sports or for riding, but never a cassowary.

That said, if provoked, both birds are equally likely to attack. 

Since cassowaries have a dagger-like sharp toenail that can even slice through limbs.


Generally, cassowaries are considered more dangerous than ostriches.

That said, an ostrich is strong enough to kick a lion to its death. 

Related articles you may be interested in

Are ostriches dangerous?

Can an ostrich kill a lion?

Now who would win between a Cassowary or Ostrich? 

Let’s find out..

Who Would Win a Cassowary Or An Ostrich?

Though most people bet on cassowary, an ostrich is far more likely to win.


No doubt, cassowaries are better equipped for a battle with their razor-sharp claw. 

However, an ostrich is bigger and heavier as well as quicker than a cassowary.

And so, in a fight between who owns a knife and who is faster, the speed often wins.

Besides, the cassowary fighting range is shorter than an ostrich.

But ostriches cannot run as smoothly as cassowaries, through hurdles.

So, if you are wondering who will win a hurdling marathon, then the winner would be a cassowary.  

They say the Cassowary is the most dangerous bird

But if they can’t win in a fight against an ostrich – What makes them so dangerous?

Carry on reading to find out..

Why Is The Cassowary The Most Dangerous Bird?

Because cassowaries are the only birds confirmed to have caused two human deaths.

The first case was reported in 1926 when a teenage hunter Phillip McClean tried to hunt a cassowary.

He fell on the ground while running, and the cassowary slashed his jugular vein, killing him on the spot. 

The second case was reported in 2019 when a cassowary attacked the owner of a private animal collection in Florida.

The 75-year-old victim suffered severe injuries and later died in the Hospital.

Regardless, cassowaries are usually quite docile. 

Besides, humans are more dangerous to them than vice versa.

With human-caused habitat destruction, they are fighting among themselves over limited territories.

Furthermore, humans have killed countless cassowaries with their motor cars.

Wrapping Up 

Cassowaries and ostriches are flightless birds that are unlikely to encounter each other.

Both differ from each other in their taxonomic orders to habitats and even organ systems.

While a cassowary has a razor-sharp toenail, the ostrich is more massive and faster.

And so, ostriches are more likely to win than cassowaries. 


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