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Animals That Start With O

orca
Two orca in Ocean. Image via Christopher Michel, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons

Welcome to animals that start with O.

Many animals begin with O. Here we list some you know and some you will soon discover. Let’s dive right in.

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Overview of Animals That Start With O

1. Ocelot

Ocelot
An ocelot (Leopardus pardalis) in Itatiba Zoo, Brazil. Image via João Carlos Medau, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Scientific NameLeopardus pardalis
Where it LivesCentral and South America
What it EatsRodents, opossums, fish, birds
Conservation StatusLeast concern

Fun fact: In the 1960s and 70s, ocelots were severely exploited due to the fur trade. Subsequent bans on this trade resulted in their populations rising once again.

Ocelots are also known as painted leopards. They are medium-sized wild cats that weigh on average 15-34 lb (7-15 kg). These carnivores prefer hunting at night in areas with dense vegetation cover. They are excellent at following scent trails and stalking their prey.

2. Octopus

Octopus color change
Rare discovery octopus color change when its asleep. Image via Betty Wills (Atsme), CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific NameOctopus spp.
Where it LivesCoastal marine waters
What it EatsCrabs, clams, fish
Conservation StatusLeast concern, 3 species endangered

Fun Fact: They are so flexible that they can pass through holes with a diameter of 1 inch.

Octopi are invertebrates including about 300 species worldwide. They prefer temperate and tropical regions and typically stay on the ocean floor in shallow waters. Octopi are highly intelligent and solitary animals. When they feel threatened, they can shoot an ink fluid to darken the water and escape.

3. Oilbird

oilbird
They are the only nocturnal flying fruit-eating birds. Image via Don Henise, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Scientific NameSteatornis caripensis
Where it LivesNorthern South America
What it EatsFruits, nuts, seeds
Conservation StatusLeast concern

Fun Fact: They consume a high-fat diet, and so, at one time in history, native South Americans consumed them for energy and used their excess fat as lamp oil.

Oilbirds are nocturnal birds located in the Northern areas of South America. They feed primarily on oil palm fruits and tropical laurels and reside in caves. They navigate using echolocation in the same way that bats do, and they are one of the few species of birds who do so. Their conservation status is currently of “least concern,” but their population numbers are decreasing due to habitat destruction.

4. Okapi

Okapi
Male Okapi in captivity at ZooParc de Beauval, located in Saint-Aignan-sur-Cher, in the department of Loir-et-Cher, France. Image via Daniel Jolivet, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Scientific NameOkapia johnstoni
Where it LivesCentral Africa
What it EatsGrasses, branches, fungi
Conservation StatusEndangered

Fun fact: They also feed on reddish clay when their food supply is scarce.

Okapis are herbivores endemic to the Democratic Republic of Congo. Their most distinctive feature is the white and black stripes on their limbs. Although their stripes may be reminiscent of zebras, they are more closely related to giraffes. In fact, they have been nicknamed the zebra giraffe. Their populations are threatened due to illegal mining activities in their habitat and hunting.

5. Old English Sheepdog

Old english sheep dog
Picture of an Old English Sheep Dog. Image by Meredith Bannan via Wikimedia
Scientific NameCanis lupus familiaris
Where it LivesWorldwide
What it EatsKibble, meat
Conservation StatusLeast concern

Fun Fact: They were bred in the 19th century in southeast England. Hence their name, Old English.

Old English Sheepdogs are a social dog breed. They have long and thick fur that often conceals their eyes, and they are white with grey patches. Their fur does not shed, except when brushed. They are intelligent and very playful pets. These dogs weigh an average of 60-100 lb (30-45 kg).

6. Olive baboon

Olive baboons
An adult monkey, the Olive Baboon (Papio anubis), grooms a kid at the Ngorongoro conservation Area in Tanzania. Image via Muhammad Mahdi Karim, GFDL 1.2 http://www.gnu.org/licenses/old-licenses/fdl-1.2.html, via Wikimedia Commons
Scientific NamePapio anubis
Where it LivesEquatorial Africa
What it EatsVariety of plants, invertebrates, birds
Conservation StatusLeast concern

Fun fact: Olive baboon males will fight for a higher-ranking position, but the decision-making within a group appears to be democratic.

Olive baboons are native to 25 countries in Africa. They live in a wide range of habitats, including grasslands, rainforests, and deserts. These baboons have greyish-brown fur, and a male adult can weigh up to 110 lb (50 kg). They are omnivores and consume a wide variety of food, which is also one of the reasons they so successfully live in many habitats. Furthermore, they have a complex social structure within groups.

7. Olm

Olms
Two olms (Proteus anguinus), in Postojna Cave, Slovenia. Image via Boštjan Burger, Public domain, via Wikimedia Commons
Scientific NameProteus anguinus
Where it LivesCentral and southeastern Europe
What it EatsShrimp, snails, insects, larvae
Conservation StatusVulnerable

Fun Fact: Olms can live for six years without feeding by slowing down their metabolisms.

Olms, otherwise known as cave salamanders or human fish, are vertebrates that live their whole lives in caves. They feed on insects that complete their life cycle in water bodies. They are white or pink in their natural habitat, but they become darker when exposed to light.

8. Opossum

opossum
North American Opossum with winter coat. Image via Cody Pope, CC BY-SA 2.5 https://creativecommons.org/licenses/by-sa/2.5, via Wikimedia Commons
Scientific NameDidelphis spp.
Where it LivesCentral and North America
What it EatsRodents, birds, eggs, fruit
Conservation StatusLeast concern

Fun Fact: Most opossum species are immune to snake venom.

Opossums are marsupials that live in areas like forests and farmland close to rivers. They have excellent balance and are good at climbing trees. Furthermore, like other marsupials, adult opossums have pouches where their babies are kept until they mature. Opossums are commonly called “possums” in North America, but these are different animals from Australasian possums.

9. Orangutan

Orangutan learn from their Mum
Orangutan learn everything they need from their mum. Image via Bruce Poon, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific NamePongo spp.
Where it LivesSoutheast China
What it EatsFruit, bark, honey, insects
Conservation StatusCritically endangered

Fun fact: They share about 97% of their DNA with humans!

Orangutans are endangered species that spend most of their time on trees. Deforestation and poaching are two of the greatest contributing factors to orangutan endangerment. They are one of the largest primates in size globally and have an omnivorous diet, although they primarily eat fruit.

10. Orb Weaver

Orb weaver
Australian garden orb weaver spider (Eriophora transmarina) at Lake Coogee . Image via Calistemon, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific Name186 genera, 3108 species
Where it LivesWorldwide
What it EatsInsects
Conservation StatusLeast concern

Fun Fact: There is evidence to suggest that orb weavers may have existed as far back as the Cretaceous period (145-66 million years ago).

Orb weavers include over 3,000 different species of spiders. These spiders are characterized by often colorful (sometimes brown), large abdomens, and have skull-like heads. Most species spin spiral-shaped webs to prey such as mosquitoes, gnats, flies, grasshoppers, and moths. Some species will even spin a new web every single day. They pose no threat to humans or pets.

11. Orca

Orca
Orca leaping out the ocean. Image via Depositphotos
Scientific NameOrcinus orca
Where it LivesOceans worldwide
What it EatsFish, seabirds, squid
Conservation StatusData deficient

Fun Fact: The killer whales also prey on the blue whales.

Orcas, otherwise known as killer whales, are found in oceans all over the world. They are predators with sharp teeth, unlike the brush-like teeth that whales have, tearing and chewing prey. Orcas were previously classified as “endangered,” but this was changed to “data deficient” until all specific species of orcas were individually classified by the IUCN.

12. Ornate Hawk-Eagle

Ornate Hawk Eagle
Ornate Hawk Eagle on branch with its head turned to the back. Image via Mdf, CC BY-SA 3.0 http://creativecommons.org/licenses/by-sa/3.0/, via Wikimedia Commons
Scientific NameSpizaetus ornatus
Where it LivesCentral America and northern South America
What it EatsBirds, mammals
Conservation StatusNear threatened

Fun Fact: Ornate Hawk-eagles also prey on bigger birds than them.

Ornate Hawk-Eagles are identifiable by the large crest of feathers on their heads. They live throughout tropical America but can be found mainly in Brazil. They are often seen perching quietly and elegantly on trees when hunting for prey.

13. Oryx

Pryx gazella
A Gemsbok (or Southern oryx) drinking alongside six Helmeted guineafowl at Chudop waterhole in Etosha, Namibia. Image by © Hans Hillewaert
Scientific NameAntilope oryx
Where it LivesArabia, north and east Africa
What it EatsGrasses, thorny shrubs
Conservation StatusLeast concern

Fun Fact: Oryxes thrive in near-desert conditions and can survive without water for long periods.

Oryxes look like antelopes but have straight horns and markings on their limbs and faces. Their main predators are big cats, like lions and cheetahs, and humans. A subspecies of oryx, known as gemsbok, is the national animal of Namibia.

14. Oscar fish

Oscar fish
An Oscar, (Astronotus ocellatus), a common aquarium fish originally from South America, seen from a three quarter view. Image via Jón Helgi Jónsson (Amything), CC BY-SA 3.0 http://creativecommons.org/licenses/by-sa/3.0/, via Wikimedia Commons
Scientific NameAstronotus ocellatus
Where it LivesTropical South America
What it EatsCatfish, shrimp, insects, fruits
Conservation StatusLeast concern

Fun Fact: Oscar fish have teeth in their throat.

Oscar fishes have a life span of 20 years. They can lay between 300–3000 eggs at one time, and the offspring is born a different color from its parents. Oscar fishes are omnivores, and they have a special suction mechanism that they use to catch prey in the water. Water that is colder than 55 °F (12 °C) is lethal to these fish.

15. Osprey

Osprey
Osprey (Pandion haliaetus) standing on nest. City Island, Bronx, New York. Image via RoySmith, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific NamePandion haliaetus
Where it LivesAll continents except Antarctica
What it EatsFish, rodents, frogs
Conservation StatusLeast concern

Fun Fact: Ospreys have a wingspan of about 5 feet.

Ospreys, otherwise known as fish hawks, have white bodies, black wings, and a black mask around their eyes. They are the second most widely distributed raptor bird, after peregrine falcons, and are a migrant species. Fish make up around 99% of their diet, but ospreys will also consume small land animals.

16. Ostrich

Ostrich
South African ostrich (Struthio camelus australis), Cape of Good Hope, South Africa. Image via Diego Delso, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific NameStruthio camelus
Where it LivesSub-Saharan Africa, Horn of Africa
What it EatsLeaves, grasses, succulents
Conservation StatusLeast concern

Fun fact: These creatures have only two toes.

Ostriches are one of the largest land animals on the earth, and they are the largest bird species. They cannot fly and instead use their wings to balance and for courtship. Ostriches are primarily found in Africa, but they are bred and farmed in many parts of the world.

17. Otter

Otter
Image of two otters cuddling. Image via Pexels
Scientific NameLutra spp.
Where it LivesNorth America, Europe, Asia
What it EatsFish
Conservation StatusSeveral species endangered

Fun Fact: The word “otter” comes from the same root word as “water.”

Otters are water-loving carnivorous mammals. There are 13 different species of otter around the world, most of which live in the northern hemisphere. River otters make up 11 species, and the other two species are sea and marine otters. They have thick fur, which allows them to float on the water surface. They have many different vocalizations including chirping, squeaking, and growling.

18. Ox

Ox
Image of a ox. Image via Pixabay
Scientific NameBos taurus
Where it LivesWorldwide
What it EatsHay, grass, grain
Conservation StatusLeast concern

Fun Fact: These creatures have been of assistance to man since around 4,000 BC.

Oxen are cattle also known as bullocks. These herbivores have been put to work for thousands of years, helping with plowing fields, transport, and carrying loads. Working oxen are often given shoes similar to horseshoes. In the wild, they travel in herds, and their predators include bears and wolves.

19. Owl

Owl
Image of a owl staring. Image via LubosHouska, CC0, via Wikimedia Commons
Scientific Name20 genera
Where it LivesWorldwide
What it EatsSmall mammals, insects, birds
Conservation StatusSome species endangered

Fun Fact: Owls can rotate their necks about 270 degrees around.

Owls are very recognizable birds with their large bodies, impressive wingspans, flat faces, bulging eyes, and protruding beaks. They are far-sighted and most of them are nocturnal. Symbolically, seeing an owl during the day counts as a bad omen. They are excellent hunters and prey on small nocturnal animals.

20. Oyster

Oyster on shell
Sydney rock oyster on half shell with two empty shells. Image via Pelagic, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Scientific NameOstreidae spp.
Where it LivesSalty or brackish coastal waters
What it EatsPhytoplankton, algae
Conservation StatusCritically endangered

Fun Fact: Some species have eyes all over their bodies.

Oysters are irregularly shaped marine creatures. They are greyish-white in color and live in oval shells in coastal waters. Oysters are highly proteinous and serve as a main source of nutrients for many animals. The main predators of oysters are seabirds, crabs, and even humans.

An oyster forms a pearl as a defense mechanism against foreign substances. When an irritant enters the oyster’s shell, it secretes a substance called nacre around the irritant, which gradually builds up to form a pearl. This process naturally protects the oyster’s delicate internal tissues.

Summary of Animals that Start with O

YouTube video
Letter O song for Kids. Source: Youtube, Uploaded: 123ABCtv

We hope you had an educative time. Why not head over to this other animal list that starts with H before you go? It’ll be worth it, we promise. See you next time.

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