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33 Animals That Start With O

By Eddie Chevrel


Updated on

How many animals do you know that start with the letter O? We’ve gathered them all on one page for you – from the hilarious orangutang to the mesmerizing octopus, all the way through to the owl and the opossum.

So without further ado, let’s find out what animals start with an O.

Animals Starting With The Letter O – The Complete List

  • Oak Toad
  • Oarfish
  • Ocellaris Clownfish
  • Ocelot
  • Octopus
  • Oilbird
  • Okapi
  • Old English Sheepdog
  • Olive Baboon
  • Olive Ridley Sea Turtle
  • Olive Sea Snake
  • Olm
  • Opossum
  • Orange-Crowned Warbler
  • Orangutan
  • Orb Weaver
  • Orca
  • Oriole
  • Ornate Chorus Frog
  • Ornate Hawk-Eagle
  • Ortolan Bunting
  • Oryx
  • Oscar Fish
  • Osprey
  • Ostrich
  • Otter
  • Otterhound
  • Owl
  • Owl Butterfly
  • Ox
  • Oyster
  • Oyster Toadfish
  • Oystercatcher

Oak Toad

The oak toad is a small amphibian that lives in the oak forests of California and Oregon. They are one of the most endangered amphibians.


The oarfish is an ancient fish that looks more like a snake than anything else. It can grow up to 50 feet long and has been known to swim up to depths of 500 meters below sea level.

Ocellaris Clownfish

These clownfish live in saltwater aquariums worldwide as pet fish, but they are also found in their natural habitat: coral reefs around Australia, Indonesia, Japan and the Philippines.


An expert hunter and climber, this large spotted cat is found throughout Central and South America and parts of the South.


Octopuses are strange, alien-like creatures that tend to live in deep water. They have eight arms and blue-green skin, and they can change colors to blend in with their surroundings. They have been known to eat anything they can catch, including fish, other mollusks, and even other octopuses.


Oilbirds are birds that live in the rainforests of South America. They nest in caves where there is a natural oil seepage from the ground below. These seeps are what gives them their name. The oilbirds eat fruit found on trees near the cave entrance and use their long beaks for drinking the oil from the seepage below before flying off into the night sky to find more food or roosting spots.


Okapis are rare animals found only in forests west of Lake Edward on the border between the Democratic Republic of Congo and Uganda; they resemble a cross between a zebra and a giraffe but are related more closely to rhinos than either one of those species. They are herbivores who eat leaves, grasses, fruits, nuts, and seeds; they also use their long tongues to reach

Old English Sheepdog

A large dog with a long, shaggy coat and a droopy face. It is known for its ability to herd sheep and other livestock. It is also a popular pet.

Olive Baboon

A species of primate in the family Cercopithecidae, which includes the macaques and baboons. It has short, brown fur and can be found in Africa, south of the Sahara Desert.

Olive Ridley Sea Turtle

A sea turtle species that live in coastal waters around Mexico, Central America and South America. It is one of only two species of turtles that can survive without eating plants at all (the other is the leatherback sea turtle).


Opossums are marsupials native to North America, but they have also been introduced in areas of South America and Australia. They have a long prehensile tail and an excellent sense of smell.

Orange Crowned Warbler

The orange-crowned warbler is a small songbird found throughout North America. It has a distinctive yellow crown around its eye that gives it its name.


Orangutans are great apes native to Indonesia and Malaysia. They have orange hair on their heads and bodies, making them look like they’re wearing wigs!

Orb Weaver

Orb weavers are spiders that spin orb-shaped webs to catch prey. The nets have sticky silk that helps trap insects before the spider goes in for the kill!

Olive Sea Snake

The olive sea snake is a giant snake that gets its name from its color. It’s usually dark brown or black, with an orange to yellow stripe down the center of its back. It lives in shallow coastal waters and reefs, feeding on fish and other creatures that live in the ocean.

Orange-Crowned Warbler

This bird is one of the most widespread warblers in North America. It can be found throughout much of Canada, the United States, and parts of Mexico. They’re known for their beautiful orange-colored crowns during breeding season-the rest of their bodies are primarily brownish-green with white streaks on their wings.

Ornate Hawk-Eagle

A species of hawk, the Ornate Hawk-Eagle, is found in parts of Asia, Africa and Europe. Its most recognizable feature is its long, golden tail feathers.

Ortolan Bunting

A small songbird that migrates between the southern United States and South America, the Ortolan Bunting has a gray back and wings with a black stripe on each wing. The male has a red throat, while the female has more brownish coloring around her throat.


A type of dolphin found in cold waters worldwide, orcas are often called killer whales because they eat other marine mammals like seals and sea lions. They are mighty hunters with thick skin that helps them hunt prey by allowing them to dive deep into the water without getting hurt by sharp rocks or ice.


A blind cave salamander native to Slovenia that lives underwater during most of its life cycle (which can last up

Ornate Chorus Frog

This frog is endemic to Brazil, where it lives in forests near water sources like streams and rivers. It spends its time near stones or vegetation where there’s standing water so that it can catch insects for food-though sometimes it will eat small fish as well! Its call sounds like a bird chirping or someone blowing bubbles through a straw into the water-it even sounds like an air horn when amplified!


It is a medium-sized antelope with long, straight and sharp horns. They are usually brown or yellowish and have a white underbelly.

Oscar Fish

It is a freshwater fish with bright orange and black stripes and can grow up to 12 inches long. They are known for their lifespan of up to 20 years and their ability to jump out of the water when they feel threatened.


It is a large sea hawk found throughout North America, Europe, Africa and Asia. They have dark plumage on top with white underneath and long wings that allow them to soar high above the water looking for prey like fish or smaller birds.


It is an African bird that stands up to 6 feet tall with long legs used for running at speeds up to 40 miles per hour, making it one of the fastest land animals globally! Their feathers are brownish-gray with black tips on both sexes, but only males have red eyes while females have blue eyes and smaller heads than males, which makes them look similar to turkeys when seen from behind!


The Otterhound is a breed of dog initially bred in England to hunt otters. It is a large, muscular dog with a square head and a long body. The species has webbed feet, which help the dog swim through water.


Owls are nocturnal birds of prey with large heads and eyes that give them excellent night vision. Their ears are hidden in their feathers, making it harder for them to hear when they fly. They have long, broad wings and sharp talons to snatch up prey or defend themselves against predators.

Owl Butterfly

The Owl butterfly is a species of butterfly that has an owl-like appearance. It has two eyespots on its wings that resemble eyes and an owl’s face when they are opened up. They can be found throughout Central America and South America.


An Ox is any member of several different species of large bovines with cloven hooves native to Africa, Asia, India, Europe, North America, Australia and South America. They have been domesticated since prehistoric times for their meat (beef), milk (milt) and labor power (oxen).


Otters are playful aquatic mammals that live in the water. They have a thick coat of fur and webbed feet to swim very fast, dive deep into the water, and catch fish.


Oysters live in coastal waters all over the world. They’re bivalve mollusks with a shell shaped like an oyster shell because they’re made up of two halves that grow together.

Oyster Toadfish

The Australian oyster toadfish is a small fish that lives in shallow waters along Australia’s east coast. It’s brownish-gray with white spots on its sides and has a large mouth with lots of sharp teeth to crush shells open so it can eat the oysters inside.


The oystercatcher is a medium-sized bird with grayish-brown plumage, a blackhead, and a beak that is red with a pink base. It breeds on coasts and islands worldwide, laying one or two eggs in a scrape, usually under rocks on the beach. The female can lay up to four clutches per year.

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About Eddie Chevrel

Eddie Chevrel is an animal journalist and the founder of ThePetSavvy. He's very passionate about exotic pets and spends most of his free time doing research, meeting, and interviewing people working with animals. Learn more about The Pet Savvy's Editorial Process.