When you think about the animals you're most afraid of, birds are probably not high on your list. We tend to recall the peaceful noises they make in the morning or the wonder of birds soaring high in the evening sky.

While there are beautiful species, some birds are less pleasing to the eye. Others are plain creepy, horrifying, and even dangerous.

Bear in mind that birds, like other wild animals, can be ruthless predators that pose a serious threat to us humans. Of the species we have in store for you today, some are more dangerous than others. Yet there is no doubt that they are all scary birds in their ways.

Ostrich (Struthio Camelus) - The Tallest Scary Birds

We should probably start the list with one of the more familiar birds in the animal kingdom. Everyone knows that ostriches are big, funny-looking birds with long necks, small heads, and large beady eyes. Just how big? Their vertical height can be as much as 9 feet, and they can weigh a whopping 330 lbs.

The fact that they cannot fly does not improve a person's chances of evading them since they have been known to run at 45 mph.

Ostriches are protective of their territory and young so that they can become aggressive. The legendary American singer Johnny Cash found this out the hard way.

In 1981 he had a terrifying encounter with an ostrich that kicked him to the ground. Despite breaking 5 of his ribs, the attack could have been worse if Johnny hadn't managed to scare the beast away.

Southern Cassowary (Casuarius Casuarius)

Some regard the cassowary as one of the planet's most dangerous birds. Like the ostrich, it is big (they can reach up to 6 feet in height) and cannot fly.

Cassowaries originate from the forests of Australia and have striking blue necks. They also have a hard shell-like feature on their heads and enormous claws.

Their mobility is impressive though it matches that of an ostrich; the cassowary can swim and run at close to 30 mph. These birds are mainly not carnivorous, but they can launch vicious attacks on any potential threats if disturbed. Their horrifying claws are capable of mauling and disfiguring humans.

Great Potoo (Nyctibius Grandis) - Cute But Scary Birds

Unlike some other scary birds, the great potoo is not dangerous to humans. What earns it a place on this list is its extremely large and creepy black eyes that belong in a horror movie.

The eyes are beneficial to the potoo because they allow the bird to see well in the dark and hunt for meals of insects and rodents. They have small holes in their eyelids so that they can see even while they sleep.

At a height of 2 feet (or less), this bird isn't as large as our first two entries.

The great potoo protects itself from predators with its excellent camouflage ― its feathers closely resemble the bark of trees in which it typically sits. The potoo got its name from the distinctive call it makes in the rainforests of South America (its natural habitat).

Shoebill Stork (Balaeniceps Rex)

Compared to other scary birds, the shoebill stork has maybe the strongest combination of creepiness, danger, and terror. It's hard to define exactly what makes it so frightening. Perhaps it's the mixture of menacing eyes and an enormous sharp beak. Or maybe it's the knowledge that they feast on snakes and baby crocodiles.

This species is found in East Africa and is hardly small with its 4.5-foot stature. You might have noticed that its Latin name ends in "rex." The shoebill stork evolved from a group of dinosaurs that the T-Rex was part of.

Unfortunately, this scary bird is vulnerable, and it is estimated that several thousand are left in the wild.

Marabou Stork (Leptoptilos Crumenifer) -eerie Scary Birds

This is another bird with an impressively long beak. The marabou stork can grow to over 5 feet tall and, despite its size, can still fly.

The wingspan of this bird can reach 8 feet which certainly helps. The marabou stork inhabits primarily the same areas as the shoebill but covers a much greater area across Africa.

The marabou is a scavenger and feeds on the dead bodies of other animals. The males of this species have another odd feature in the form of a large air sac that hangs from their necks. These are used to attract mates and also to scare away predators.

King Vulture (Sarcoramphus Papa) - Colorful Scary Bird

Like the marabou stork, the king vulture has a bald, featherless head because it too is a scavenger. The lack of feathers helps it to stay clean when devouring animal carcasses.

The king vulture's main home is in Brazil but can be found as far north as Mexico and as far south as Argentina.

Their bodies are covered in black and white feathers, while their skulls have a beautiful array of colors. If you see them and their 5.5-foot wingspan swooping overhead, you might just forget about their color scheme.

The scary bird appears in ancient Mayan folklore, where it was claimed that they deliver messages to Gods. Regardless of whether that's true, it shows that the king vulture is an effective predator that has stood the test of time.

Martial Eagle (Polemaetus Bellicosus)

This is the largest eagle in Africa and is another ferocious carnivore whose wingspan can reach 6 ft 4 in. With a weight of 14 pounds, the martial eagle packs a punch when in full flight. It can knock a grown man over or break a person's arm.

The martial eagle is an intimidating and scary bird, but humans can be thankful for their eating habits. They tend to hunt poultry such as chickens and guineafowl and have been known to target larger prey, including goats, lambs, and monkeys.

Hooded Pitohui (Pitohui Dichrous)

Is this a scary bird? Not really. Is it unnerving? Somewhat. So how does that justify its place on this list?

The appearance of the hooded pitohui is deceiving because it is very toxic. It feeds on poisonous beetles to get the necessary supply of toxins for its attractive orange and black feathers.

Anyone tempted to hold or stroke this bird should remember that the neurotoxin it possesses can kill. Otherwise, there is nothing especially remarkable about the hooded pitohui.

They have strong claws, are several inches tall, and are omnivores.

Pelican (Pelecanus Onocrotalus)

We haven't finished with enormous beaks just yet. The pelican should be familiar to most people and is related to the shoebill stork, mentioned earlier. These aquatic birds reside all around the world, from Europe to Africa, Asia, and Australia.

What's most alarming about these birds is how they consume their prey. They simply swallow fish whole.

When pelicans open their mouths fully, the enormous gaping pit they reveal is a remarkable sight. Their formidable 10-foot wingspan is another intimidating feature of this scary bird.

Greater Adjutant (Leptoptilos Dubius) - Intriguing Scary Birds

The greater adjutant is another giant bird. It can be as tall as 5 feet and have a wingspan of 8 feet. It is not a fussy eater and is happy to consume insects, rodents, birds, and reptiles alike. The adjutant is native to Southern and Southeast Asia.

The greater adjutant is not a pretty bird but still has an intriguing appearance.

It has wafer-thin legs, a white beak, dark blue feathers, and an orange pouch on its neck. This is another endangered species, with just over 1000 still in the wilderness.