Animals that Start with O

Oak toads are the smallest of the toad species in North America, easily identified by a mid-dorsal, light stripe with variable black and brown spots. They have proportionally large parotoid glands. Most toads have that distinctive round vocal sound. The calling oak toad male has an elongated vocal sac. It extends significantly as they produce […] Read More

The Giant oarfish (Regalecus glesne) holds the Guinness Book of World Records for the longest bony fish in the world. They are found in the depths of the Mediterranean sea and the eastern Atlantic Ocean and have a ribbon-like appearance. Oarfish are members of the Refalecidae family and are also known as the King of […] Read More

Summary The ocean perch (Sebastes alutus) is a commercially important fish in the North Pacific. It ranges along the Pacific coasts of the United States, Canada, Japan, and Russia. Distinguishing marks of this moderately-sized marine species include a reddish body and dorsal spines. They are deepwater bottom-dwellers, living at depths up to 2,700 feet. 5 […] Read More

Zoarces americanus belongs to the eelpout family Zoarcidae. You can find this large eelpout species throughout the northwest Atlantic Ocean. It is a predatory bottom feeder that lives at a wide range of depths. Its blood possesses an antifreeze protein that enables it to withstand frigid waters. Although commercial fisheries don’t regularly harvest them, the […] Read More

Summary A staple in Southern California, the ocean whitefish is a member of the tilefish family Malacanthidae. While commonly caught as bycatch, ocean whitefish aren’t actively targeted by most commercial fisheries in the United States. They are highly active and mostly solitary outside of the spawning and mating season. During the day, they come to […] Read More

Unlike most sharks, the oceanic whitetip shark is known for being opportunistic and aggressive. The oceanic whitetip shark is a critically endangered species that inhabit tropical waters. They have white tips on their fins, hence the species’ name. 5 Oceanic Whitetip Shark Facts Aggressive: Unlike most sharks, many experts consider this species aggressive. As opportunistic […] Read More

“Its specific name, ocellata, refers to the spots, or ocelli, on their tail feathers.” Summary The ocellated turkey (Meleagris ocellata) is endemic to the Yucatán Peninsula and parts of Belize and Guatemala. These birds are somewhat elusive and hard to catch, but they are noisy with distinctive gobbles. They live in tropical and evergreen forests, […] Read More

Classification and Evolution The Ocelot is a medium-sized small cat that is native to the jungles of South America. The Ocelot is also known as the Painted Leopard due to the beautifully distinctive markings on its fur as it displays dark rosettes, along with spots and stripes. Similar in coloration to the much smaller but […] Read More

The octopus holds the distinction of being the most intelligent of all invertebrate animals. With the highest brain-to-body-mass ratios of all invertebrates – higher even than those of some vertebrates – the octopus is regarded as the smartest of all invertebrate animals. These cephalopods are intelligent enough to engage in deceitful activities, including pretending to […] Read More

The Oenpelli python is a long, thin snake that reaches 16 feet and can change color. This species lives in a tiny region in Northern Territory, Australia. It is one of the rarest python species in the world. Amazing Facts About Oenpelli Pythons Where to Find Them This species only lives in Northern Territory, Australia. […] Read More

“The oilfish is an opportunistic carnivore, eating what is abundant and easy to catch in its environment.” Summary The oilfish (Ruvettus pretiosus) is a species of snake mackerel found in the temperate and tropical waters in the Atlantic and Pacific Oceans. They inhabit deep waters, living in pairs and silently swimming through the dark water. […] Read More

Due to its long prehensile tongue, the okapi is one of the few animals in the world said to be able to lick its own ear! The okapi is an elusive herbivore present in only central Africa in a small area of tropical mountain forest. It has a long neck, in common with its close […] Read More

With its big shaggy coat, obscured eyes, and white and gray color scheme, the Old English Sheepdog is one of the most recognizable breeds in the world. Its very appearance seems to radiate friendly and approachable energy. History and Origin This breed originated at some point in the 19th century from the region of Cornwall […] Read More

These beetles are known as pests because of their harmful ability to destroy wood. Older house borers are second only to termites in terms of the damage they cause. However, despite its name, the old house borer prefers newer wood. This is because fresher wood has a higher resin content. These beetles were first identified […] Read More

The oleander hawk moth (Daphnis nerii) belongs to the hawk moth family. They’re most active at twilight. Due to their stunning appearance, Daphnis nerii is sought by naturalists, lepidopterists, and photographers. The larva of the oleander hawk moth is sometimes a pest, as it feeds on some plants such as the oleander plant (hence the […] Read More

“Olingos are part of the raccoon family.“ Olingo Facts They possess anal scent glands which produce a pungent odor when the animal is scared. This is designed to drive enemies away. They are nocturnal animals. They are active in the night and sleep in tree cavities during the day. Although they are omnivores, they mostly eat fruit, […] Read More

“The olive baboon forms one of the most complex social structures in the animal kingdom.” This baboon is a type of old-world monkey (a monkey species from the Eastern Hemisphere) that roams across various habitats of Africa. They have numerous adaptations to help them survive and thrive in different environmental conditions. In this article, you […] Read More

The olive python is Australia’s third longest snake; only the Oenpelli python and amethystine python are longer. This very long but relatively docile snake is sometimes killed because people confuse it with the venomous king brown snake (Pseudechis australis). It is long and strong, and the adults often reach 13 feet long. The Pilbara olive […] Read More

“Olive sea snakes can stay underwater for two hours without taking a breath” The olive sea snake is sometimes called the golden sea snake or the olive-brown sea snake because of its coloration. It can grow up to six feet long and weigh up to six and a half pounds. It has a venomous bite […] Read More

The olm is the longest-living amphibian and can live to be 100 years old! One of the most fascinating creatures in a world full of fascinating creatures, the olm, like its distant relative the axolotl, is a completely aquatic salamander with gills and tailfins. It is born, lives its long lifespan, and eventually dies in […] Read More

The Olympic marmot is an endemic species found only in the Olympic Mountains of Washington. The species is the second-rarest North American marmot. This furry rodent hibernates without eating or drinking for seven to eight consecutive months from fall to late spring, relying on accumulated body fat and a much-reduced metabolism.  5 Olympic Marmot Facts […] Read More

The Onagadori chicken of Japan has the longest tail in the world, with feathers growing up to 27 feet in length! The ornamental Onagadori chicken originated centuries ago in the Kochi Prefecture in Japan. These extremely long-tailed chickens were bred to preserve a mutation that prevented tail feathers from molting. This mutation allowed the birds […] Read More

An onager’s coat changes color with the season. Facts Endangered: Onagers are an endangered species of equines. Only 28,ooo exist in the world today.Almost extinct: Only 600-700 Persian onagers are left in the wild today.Good memory: Onagers are very intelligent animals. They have a great memory and can recall the face of someone they met […] Read More

One of the things studying earth’s ancient fossils has revealed is that the planet had some pretty odd creatures millions of years ago. Opabinia is one of such strange-looking creatures that swam the earth’s oceans 500 million years ago. Unearthed from Canada’s Burgess Shale, this ancient arthropod had an odd appearance; it looked like something […] Read More

The opah is a large, colorful fish that makes a prize catch and a tasty meal. Opah are a family of large, circular fish that live mostly in tropical waters. They are brightly colored with red-orange fins and silvery bodies. They can grow up to 6 feet, making them a great catch for fishermen who […] Read More

Opaleye is a species of fish indigenous to the Pacific coast of North America. It is a member of the Pleuronectidae family, which includes other flatfish such as soles and flounders. They live in rocky tide pools and intertidal areas where they can reach lengths of up to 25 inches and weigh 13 pounds fully […] Read More

Opossums hold the distinction of being the only marsupial that lives in the United States and Canada! Throughout much of United States history, opossums were animals that were widely hunted and consumed by people. Although this remains true in some areas of the southern U.S., these savvy marsupials are now better known as pests due […] Read More

Summary The Oranda goldfish is a fascinating breed of goldfish from the Carp family that was developed in the aquarium trade industry and originated from China and Japan. The Oranda is a type of ornamental goldfish that is known for its wen- which resembles a large jelly-like growth on their heads. This type of goldfish […] Read More

The orange baboon tarantula is both orange and ornery. The orange baboon tarantula (OBT) is covered in bright orange bristles. Their faces resemble furry, orange baboons. OBT’s, as they are sometimes referred to, are known to have an ornery disposition and can act aggressively. They can grow to be similar in size to the Mexican […] Read More

The orange dream ball python is a popular color morph that started as a mutation. These snakes have bright orange instead of brown markings with a white belly. One of the hundreds of color mutations in ball pythons, orange dream combines with others to create bright and beautiful color patterns. 3 Facts About The Orange […] Read More

Summary Able to live over 200 years, the orange roughy is a deep-sea fish belonging to the slimehead family Trachichthyidae. They mature extremely slowly, which makes them highly susceptible to overfishing. They possess rounded heads covered in mucous-filled canals, hence their name.  When active or feeding, they tend to appear orangish-red, but they slowly lose […] Read More

“Orange spiders make vertically oriented webs for catching prey.” The marbled orb weaver, popularly known as the orange spider, looks like a pumpkin with legs, thanks to a distinct orange color and inflated abdomen. It is one of the most common garden spiders in North America. The species makes vertically oriented webs on trees, shrubs, […] Read More

“It lives in the lowlands of the Amazon rainforest.” Summary The orange tanager (orange-headed tanager) is a small bird native to the neotropical region of South America. It spends its days foraging in trees and shrubs for insects, often with a small group. Though relatively uncommon, they have an extensive range and learn to adapt […] Read More

The orange-crowned warbler is a unique songbird who primarily lives in the western hemisphere. This bird has a high-pitched trill for a song, and males even have different songs to differentiate them from each other. Both parents take care of the young, though only the mother incubates the eggs for just under 2 weeks. Orange-Crowned […] Read More

Classification The orangutan is one of the largest primates in the world and is the only member of the great ape family that is found outside of Africa. There are three species of orangutan found in the steamy jungles on the islands of Borneo and Sumatra, which are the Bornean orangutan, the Sumatran orangutan, and […] Read More

The Orb Weaver is a spider commonly found outside homes, in hedges, tall grasses, and trees. They are a helpful predator who feeds off the pest bugs we don’t like, such as mosquitoes, beetles and other bothersome flying insects. They build elaborate, circular webs and are most often seen in late summer and early fall. […] Read More

“They are easy-going birds who show little aggression toward other bird species.” Summary The orchard oriole (Icterus spurius) is a small passerine bird native to North and South America, inhabiting orchards and woodland edges. These social birds are easy-going and show little aggression, often joining mixed-species groups. Listen for the male’s rapid musical songs during […] Read More

This fish camouflages as its prey’s parents to trick it into becoming dinner. Facts The orchid dottyback is a brilliantly purple fish. They are sought after by aquarium owners to spruce up their tank’s appearance.The orchid dottybacks; generic name, Pseudochromis, means false color, because the fish has the ability to mimic the colors of its […] Read More

The Oregon spotted frog is an endangered species of frog native to the Pacific Northwest. It has a range spanning Canada and the United States, although most of the frogs no longer inhabit these regions due to their rarity. They have characteristic black spots with light centers and spend most of their time in the […] Read More

The ori-pei is a hybrid mix breed of purebred parents, namely the Chinese shar-pei and pug. The ori-pei originated in North America in the year 1970. A Chinese shar-pei breeder, Aaron Silver, grew very fond of the shar-pei breed but disapproved of their health issues. At that time, he decided to create a hybrid breed […] Read More

Summary Oribis are unique little antelope because they can adapt well to most environments, which is why they can be found scattered across the African continent. While there are a few solitary males, they generally live in breeding pairs or groups of three, consisting of one male and two females. Female oribis sexually mature at […] Read More

Unlike other cockroach species that live indoors living off humans, oriental cockroaches are outdoor scavengers.  Summary The Oriental cockroach is a large, shiny cockroach with a dark brown or almost black color. Like other cockroach species, oriental cockroaches are scavengers. However, they live in outdoor habitats rather than indoors. Oriental cockroaches are also called water […] Read More

“They like to live near forest streams and ponds with plenty of canopy shade.” Summary The oriental dwarf kingfisher (Ceyx erithaca), also known as the black-backed kingfisher, is a tiny bird only slightly bigger than a hummingbird. They live in southeast Asia, where they inhabit evergreen and deciduous forests near streams and ponds. They stay […] Read More

“Orinoco crocodiles are the largest predators in South America; they’re also going extinct!” Facts Orinoco crocodiles are the largest predators in South America. They are also apex predators which means they sit comfortably at the top of the food chain.A living fossil: You can trace the Orinoco crocodile back 240 million years ago! They also […] Read More

The ornate bichir can survive outside water for long periods of time.  Summary Polypterus ornatipinnis, also called ornate bichir, is a species of freshwater fish native to Central and Eastern Africa. More specifically, the fish is found in Lake Tanganyika and the Congo River Basin. This fish is the largest of the “upper jaw bichirs” […] Read More

Ornate black-tailed rattlesnakes are among the most beautiful snakes in the Americas. These mild-mannered snakes usually slither away before giving away their position by rattling. But be careful not to step on them because they can deliver a painful venomous bite.  Their lack of legs allow them to slither in and out of places off […] Read More

“Ornate box turtles can live up to 40 years in the wild!” Ornate Box Turtle Summary The ornate box turtle is one of two commonly found land turtles in the plains of the USA. The animal is the state reptile of Nebraska and Kansas and is commonly found in the grasslands in both states. Unlike […] Read More

The Ornithocheirus was a pterosaur (flying reptile) that lived during the Albian Stage of the Early Cretaceous Period, about 110 million years ago. Fossils of the Ornithocheirus have been found in the United Kingdom and Morocco. The Ornithocheirus was a flying predator. It was a piscivore, which means it hunted and primarily ate fish. It […] Read More

Description & Size of the Ornithomimus Ornithomimus is a genus of ornithomimid dinosaur, and its name translates from Greek to mean “bird mimic.” As you imagine what you think of a dinosaur, you’ll be surprised to find that the Ornithomimus looks nothing like it. Compared to other dinosaurs, the Ornithomimus was a medium-sized animal. When […] Read More

“The Ortolan Bunting is The Little Bird That is Forbidden Food” Of all the weird gastronomic traditions humans indulge in, eating this inoffensive little bird is one of the weirdest and frankly, one of the cruelest. Yet it is a rite of passage for the well-heeled, as can be seen in TV shows such as […] Read More

“An intelligent and companionable fish” People who own Oscar fish might have bought one or two for their beautiful colors, but soon they’re surprised to see that the fish has a personality. They’ll notice their pet Oscar seems to be watching them as they go about their business. They may even believe that their Oscar […] Read More

“Their wings make an “M” shape when seen from below.” Summary The osprey (Pandion haliaetus) is a large raptor inhabiting every continent except Antarctica. They live near bodies of water abundant with fish, such as coastal estuaries and salt marshes. Look for them soaring above the water and diving feet first to catch their prey […] Read More

The most common of ancient crustaceans, ostracods are tiny crustaceans in the class Ostracoda. Scientists have identified around 70,000 individual ostracods, but only 13,000 or so exist to this day. While most ostracods live in marine habitats, some also live in freshwater, and a few live on land. They range in size from 0.008 to […] Read More

The ostrich is among the largest types of birds in the world. The ostrich bird looks like an unusual chimera cooked up in a lab. When writing about the ostrich, the Greek philosopher Aristotle did not know whether to classify it as a bird or a mammal. But in fact, the ostrich belongs to that […] Read More

“Giant otters are notorious chatterboxes“ Just like many people, there are giant otters that are considered chatterboxes for their species. Though they can’t form words, they have a vocabulary that consists of 22 recognizable noises. Each noise is used to address a different type of situation. This is how giant otters effectively communicate with each […] Read More

Otterhounds have webbed feet and are expert swimmers! The history of this shaggy dog dates all the way back to 14th century England. These dogs were bred to hunt otters and remove them from streams and lakes. This is so otters couldn’t steal the fish away from fishermen in the area. Bloodhounds and French hounds […] Read More

The ovenbird is named for its unusual nest, which is shaped like an oven! The ovenbird is kind of punk rock. It wears a jacket of olive feathers and has an orange mohawk-like stripe down the middle of its crown, lined on either side in black. When it gets agitated it can raise this stripe […] Read More

The Oviraptor is a genus of oviraptorid dinosaur. The name is Latin for “egg thief,” which is what scientists originally believed it to be. However, additional research suggests that the parents of this species were quite protective, protecting a nest instead of attacking it as food. Oviraptors ruled in big numbers during the late Cretaceous […] Read More

Owls are exceptional hunters that can spot potential prey from up to half a mile away. Owls are a diverse group of animals that belong to their own separate order. There are more than 200 recognized species all around the world. With their highly developed binocular vision and accurate flying abilities, they have several unique […] Read More

The owl butterfly is a fascinating specimen native to the rainforests of Central America. They derive their name from big spots on each hindwing that resemble owl eyes. These spots are not decorative; they are a defense mechanism used to deter birds from eating them. This species belongs to the family Nymphalidae, consisting of large-sized […] Read More

The name “owlfly” applies to any member of the large Ascalaphidae family of insects. They have long slender bodies with membranous wings. The appearance of the owlfly is similar to that of the dragonfly, and both insects are often mistaken for each other. The larvae of this insect are ambush predators typically found on trees […] Read More

The ox is the heavy-duty machinery of the animal world. An ox, by definition, is any male bovine that is used for work. Usually, only mature males (over 4 years of age) from the largest breeds of domesticated cattle are trained for work, and these males are castrated to keep them docile. Certain cattle are […] Read More

The oxpecker, known as the rhino’s guard, alerts its host to danger with a loud commotion! The oxpecker is a native of sub-Saharan Africa that spends most of its life on the backs of its hosts. It feeds on ticks, larvae and other parasites that infest large mammals like the black rhinoceros, African buffalo, hippopotamus […] Read More

Oysters make up a family of a large number of salt-water bivalve mollusks. Oysters are marine animals that are often found in brackish habitats. They are very irregular in shape and the valves of some are highly calcified. They belong to the phylum Mollusca. Oysters are animals that eat algae and other food particles that […] Read More

“The oyster toadfish is also known as the ugly toad.” The oyster toadfish is a strange-looking (some may even say ugly) fish that makes its home in the secluded holes and hiding spots along the shore of the eastern United States. The bumpy skin, long mouth, and bulging eyes have earned it very appropriate comparisons […] Read More

“Ozark bass only inhabit the tributaries of White River, and very little is known about them.” Summary Native to White River tributaries in Arkansas and Missouri, Ozark bass populations do not reach far. The fish species is unique in that they cannot be found anywhere else in the United States. Their concentrated population has not […] Read More