103 Animals That Start with R: From Sneaky Raccoons to Majestic Reindeer

There are so many animals on our planet that it’s impossible for one person to remember them all. Even just looking at animal species starting with R, there are countless options.

This includes all kinds of animals, like adorable small mammals, birds with striking colors, and bizarre invertebrates. Keep reading to find out more about some of these creatures.

List of Animals

Here are 103 animal species that start with the letter R.

Click an animal name to jump to its full description, image, and more below.

Animal	Type	Region
Raccoon	Mammal	North and South America
Raccoon Dog	Mammal	Eastern Asia
Radiated Tortoise	Reptile	Southern Madagascar
Raggiana Bird-of-Paradise	Bird	New Guinea
Rainbow Bee-Eater	Bird	Southern Australia
Rainbow Boa	Reptile	Central and South America
Rainbow Grasshopper	Insect	Western United States
Rainbow Kribensis	Fish	West Africa
Rainbow Lorikeet	Bird	Australia
Rainbow Pitta	Bird	Western Australia
Rainbow Shark	Fish	Southeast Asia
Rainbow Trout	Fish	North America and Asia
Rakali	Mammal	Australia
Razorbill	Bird	Northern Atlantic Ocean
Red Avadavat	Bird	Tropical Asia
Red Deer	Mammal	Europe and Western Asia
Red Diamond Rattlesnake	Reptile	Southwestern California and Baja California
Red Fox	Mammal	Northern Hemisphere
Red Giant Flying Squirrel	Mammal	Southeast Asia
Red Hartebeest	Mammal	Southwestern Africa
Red Panda	Mammal	Eastern Himalayas
Red Paper Wasp	Insect	Eastern United States
Red River Hog	Mammal	West and Central Africa
Red Ruffed Lemur	Mammal	Eastern Madagascar
Red Spitting Cobra	Reptile	East Africa
Red Squirrel	Mammal	United States and Canada
Red Triangle Slug	Mollusk	Eastern Australia
Red-Backed Salamander	Amphibian	Eastern North America
Red-Bellied Black Snake	Reptile	Eastern Australia
Red-Billed Gull	Bird	New Zealand
Red-Billed Quelea	Bird	Sub-Saharan Africa
Red-Crested Cardinal	Bird	Southeastern South America
Red-Crowned Crane	Bird	Eastern Asia
Red-Crowned Roofed Turtle	Reptile	India, Bangladesh, and Nepal
Red-Eared Slider	Reptile	United States
Red-Eyed Crocodile Skink	Reptile	New Guinea
Red-Eyed Tree Frog	Amphibian	Southern Mexico and Central America
Red-Faced Spider Monkey	Mammal	Northern South America
Red-Footed Booby	Bird	Pacific, Atlantic, and Indian Oceans
Red-Footed Tortoise	Reptile	South America and Caribbean Islands
Red-Handed Tamarin	Mammal	Brazil, Guyana, French Guiana, and Suriname
Red-Headed Rock Agama	Reptile	Sub-Saharan Africa
Red-Headed Vulture	Bird	Northern India
Red-Headed Woodpecker	Bird	Temperate North America
Red-Lipped Batfish	Fish	Pacific Ocean (Galapagos Islands)
Red-Necked Wallaby	Mammal	Eastern Australia
Red-Shanked Douc	Mammal	Vietnam, Laos, and Cambodia
Red-Shouldered Hawk	Bird	Eastern North America and coastal California
Red-Tailed Hawk	Bird	North America
Red-Tailed Monkey	Mammal	Central Africa
Red-Wattled Lapwing	Bird	West and South Asia
Red-Winged Blackbird	Bird	North America
Redback Spider	Arachnid	Australia
Reddish Egret	Bird	Central America, Mexico, southern US
Redtail Catfish	Fish	Amazon and Orinoco River basins
Reeve’s Muntjack	Mammal	Southeastern China
Regent Bowerbird	Bird	Eastern Australia
Reindeer	Mammal	Northern Hemisphere
Resplendent Quetzal	Bird	Southern Mexico to Panama
Reticulated Giraffe	Mammal	Somalia, southern Ethiopia, northern Kenya
Reticulated Python	Reptile	Southeast Asia
Rhim Gazelle	Mammal	Sahara Desert
Rhinoceros Auklet	Bird	Pacific Ocean
Rhinoceros Hornbill	Bird	Southeast Asia
Rhinoceros Iguana	Reptile	Hispaniola
Rhinoceros Ratsnake	Reptile	Northern Vietnam to Southern China
Ribbon Eel	Fish	Indian and Pacific Oceans
Ribbon-Tailed Astrapia	Bird	Papua New Guinea
Ring-Billed Gull	Bird	North America
Ring-Necked Snake	Reptile	North America
Ring-Tailed Lemur	Mammal	Southern Madagascar
Ring-Tailed Vontsira	Mammal	Madagascar
Ringed Kingfisher	Bird	Mexico to South America
Ringed Seal	Mammal	Northern Pacific Ocean
Risso’s Dolphin	Mammal	Pacific, Atlantic, and Indian Oceans
Riverine Rabbit	Mammal	South Africa
Rock Bass	Fish	Eastern North America
Rock Hyrax	Mammal	Africa and the Middle East
Rock Monitor	Reptile	Africa
Roe Deer	Mammal	Europe and Asia
Roosevelt Elk	Mammal	Pacific Northwest
Rose-Breasted Grosbeak	Bird	North and South America
Rose-Ringed Parakeet	Bird	Africa and South Asia
Roseate Spoonbill	Bird	South America and southern North America
Rosy Boa	Reptile	California, Arizona, and Baja California
Rosy-Faced Lovebird	Bird	Southwestern Africa
Rough Green Snake	Reptile	Southeastern United States
Rough-Legged Buzzard	Bird	Northern Hemisphere
Rough-Skinned Newt	Amphibian	Pacific Northwest
Rough-Toothed Dolphin	Mammal	Tropical and warm temperate oceans
Royal Penguin	Bird	Macquarie Island and nearby islands
Rubber Boa	Reptile	Western United States and British Columbia
Ruby-Crowned Kinglet	Bird	North America
Ruby-Throated Hummingbird	Bird	Eastern North America
Ruddy Duck	Bird	North and South America
Ruddy Turnstone	Bird	Worldwide
Ruffed Grouse	Bird	Canada and northern United States
Rufous Hornbill	Bird	Philippines
Rüppell’s Fox	Mammal	North Africa
Rüppell’s Vulture	Bird	Sub-Saharan Africa
Russell’s Viper	Reptile	Indian subcontinent
Russian Tortoise	Reptile	Central Asia
Rusty Blackbird	Bird	Canada and eastern United States

1. Raccoon

• Scientific Name: Procyon lotor
• Habitat: Near wooded areas across North America, along with parts of South America
• Size: 10 to 20 pounds
• Diet: Fruits, nuts, insects, fish, small mammals, amphibians, carrion

Raccoons are extremely adaptable, so they can thrive in a wide range of environments and eat a variety of foods. They usually wash their food in the water before they eat it, but it might not be to clean it. Instead, research suggests that getting their hands wet might help them learn more about the food they’re holding. Their paws are very similar to human hands, allowing them to open trash cans, unscrew lids, and turn doorknobs to access food. Their problem-solving abilities are similar to those of a young child.

2. Raccoon Dog

• Scientific Name: Nyctereutes procyonoides
• Habitat: Wooded areas of eastern Asia
• Size: 9 to 20 pounds
• Diet: Insects, rodents, amphibians, birds, fish, fruits, nuts, carrion

While raccoon dogs, more specifically known as common raccoon dogs, look very similar to raccoons, they’re more closely related to foxes, making them canines. They’re the only canines known to hibernate in the winter. They’re social creatures that usually live in family groups and hunt in pairs. Like raccoons, they eat almost anything they can find, including poisonous toads, since they can use their saliva to dilute the toxins. There’s one other species of raccoon dog, known as the tanuki or Japanese raccoon dog.

3. Radiated Tortoise

• Scientific Name: Astrochelys radiata
• Habitat: Dry, arid environments of southern Madagascar
• Size: 6 to 30 pounds
• Diet: Grasses, fruits, succulent plants

Radiated tortoises are herbivores that spend most of their time grazing on grass. About 80% to 90% of their diet consists of grazing. They mostly graze in one area, as if to keep that area trimmed down at all times. Like other tortoises, they have nerves and blood vessels in their shells, so they can feel when someone or something touches them. They typically live 40 to 50 years, but some radiated tortoises have lived for 100 years.

4. Raggiana Bird-of-Paradise

• Scientific Name: Paradisaea raggiana
• Habitat: Dense forests of New Guinea
• Size: 13 inches long
• Diet: Fruits, insects

These birds are striking because the males have long, fluffy yellow and white tail feathers. They use these feathers in a mating display, which involves raising and shaking their tail feathers as if they’re dancing. Like other bird-of-paradise species, these animals can be loud. They have a variety of unique vocalizations used to announce their territory, call to mates, and make alarm sounds to warn others.

5. Rainbow Bee-Eater

• Scientific Name: Merops ornatus
• Habitat: Open forests of southern Australia
• Size: 9.1 to 11 inches
• Diet: Insects (primarily bees and wasps)

Rainbow bee-eaters earned their name by eating the insects that many other creatures avoid. They catch bees and wasps in mid-flight, and then they hit them against trees to remove the stingers. They’re immune to venom from their prey, but they often squeeze venom out of insects before eating them as a precaution. One rainbow bee-eater can consume up to 300 bees and wasps daily.

6. Rainbow Boa

• Scientific Name: Epicrates cenchria
• Habitat: Humid forests across Central and South America
• Size: 4 to 6 feet long
• Diet: Small mammals, birds

While rainbow boas are red and brown with dark markings, they appear iridescent when the light hits them, making them look rainbow from certain angles. They’re most active at night, but they may bask in the sun during the day if nights are too cold for them. They’re solo creatures that use heat sensors in their jaws to locate prey on the forest floor. Most of the time, they hunt land animals, but they’re excellent swimmers that can hunt aquatic prey if needed.

7. Rainbow Grasshopper

• Scientific Name: Dactylotum bicolor
• Habitat: Prairies and desert grasslands of the western United States
• Size: 0.8 to 1.4 inches
• Diet: Plants

While most grasshoppers are green to blend in with plants, rainbow grasshoppers are a mixture of bright red-orange, yellow, and blue-black. They’re toxic, so their bold coloring is to warn predators not to eat them. Their colors vary slightly based on their location. While most grasshoppers have wings, this species doesn’t, which prevents them from flying. They can still hop long distances to protect themselves, but luckily, most threats are deterred by their appearance.

8. Rainbow Kribensis

• Scientific Name: Pelvicachromis pulcher
• Habitat: Coastal regions of West Africa
• Size: 3 to 5 inches
• Diet: Algae, vegetation, insects

Rainbow kribensis, which is often shortened to rainbow kribs, is a cichlid species with beautiful yellow, pink, and blue markings. While they often travel in pairs, they can act aggressively if there are too many fish nearby. They sometimes nip at the fins of other fish, especially those with long, flowing fins. Females are typically much smaller than males, but they’re also more colorful.

9. Rainbow Lorikeet

• Scientific Name: Trichoglossus moluccanus
• Habitat: Rainforests and woodlands of Australia
• Size: 9.8 to 11.8 inches
• Diet: Pollen, nectar, fruits, vegetables

Rainbow lorikeets have a beautiful display of colors, including red, blue, green, yellow, and orange. They’re noisy birds that frequently travel around in pairs or small groups. They have unique brushes on the tips of their tongues, making it easy for them to collect their main food sources, pollen and nectar. They’re sometimes kept as pets because of their unique ability to mimic human words and phrases.

10. Rainbow Pitta

• Scientific Name: Pitta iris
• Habitat: Forests of Western Australia
• Size: 6.3 to 7.1 inches
• Diet: Worms, insects, snails, insect larvae

Even though most of this bird is black, it has some vibrant rainbow colors, including green and blue on the wings and red on the head. They forage for invertebrates in the soil. If they find prey with hard exteriors like snails, they drop them on roots to break the shell. When these birds feel threatened, they quickly flick their wings open a few times while making a loud call to scare away threats.

11. Rainbow Shark

• Scientific Name: Epalzeorhynchos frenatum
• Habitat: Sandy river bottoms of Southeast Asia
• Size: 6 inches
• Diet: Algae, plants

Despite being called a shark, rainbow sharks aren’t true sharks. Instead, they’re a type of bony, ray-finned fish that has a similar shape to a shark. They have sensory whiskers called barbels that help them navigate across sandy substrate. They come in a wide range of colors, including orange, red, black, blue, gray, and albino. Scientists have even created a genetically modified version of the species that glows in the dark.

12. Rainbow Trout

• Scientific Name: Oncorhynchus mykiss
• Habitat: Rivers, lakes, and streams across North America and Asia
• Size: 12 to 24 inches
• Diet: Insects, fish, frogs

Due to their large size and wide distribution, rainbow trout are a popular fish for fishermen to catch. They can live in both freshwater and saltwater environments, and they can be distinguished by their speckled green skin with pink bellies. When it’s time for them to lay eggs, they almost always return to the place where they were born. They don’t stray far from that location in the first place, so it’s not hard for them to go back.

13. Rakali

• Scientific Name: Hydromys chrysogaster
• Habitat: Slow-moving streams across Australia
• Size: 9 to 15 inches
• Diet: Fish, aquatic insects, crustaceans, mollusks, aquatic plants

Rakalis are also known as Australian otters or water rats. While they primarily eat fish and insects, they will eat almost anything they can find, which could even include small mammals. They search for food both during the day and at night. They often have a flat area on land that they carry their food to when they eat it. Their back feet are partially webbed to help them swim quickly and effortlessly.

14. Razorbill

• Scientific Name: Alca torda
• Habitat: Oceanside cliffs near the northern Atlantic Ocean
• Size: 14 to 17 inches
• Diet: Fish, mollusks, crustaceans

Razorbills are named for their sharp bills with unique patterns. They use their bills to help them capture prey and firmly grasp it. In some cases, they may even use their bills to protect themselves. They can dive as deep as 300 feet below the water’s surface, but they do most of their hunting at about 20 to 30 feet deep. They can swim quickly by using their wings to propel themselves as if they’re “flying” underwater.

15. Red Avadavat

• Scientific Name: Amandava amandava
• Habitat: Open grasslands of tropical Asia
• Size: 3.5 to 3.9 inches
• Diet: Seeds, insects

Red avadavats are sometimes called strawberry finches because their red coloring with white spots resembles the seeds on a strawberry. Females are usually a duller color with fewer spots than males. They typically travel in small flocks, where they land in dense vegetation to help them stay hidden. They primarily use their strong beaks to eat seeds, but they may also eat insects like termites when seeds aren’t available.

16. Red Deer

• Scientific Name: Cervus elaphus
• Habitat: Woodlands of Europe, along with Iran, Anatolia, and areas of Western Asia
• Size: 150 to 250 pounds
• Diet: Grasses, tree shoots, sedges, herbs, shrubs

The red deer is a large deer species with reddish-brown fur. These mammals have likely been around for a long time because they were depicted in cave paintings from over 40,000 years ago. Males have large antlers that are up to 3 feet long, which they can use to defend themselves. Every spring, they shed their antlers, and they grow back larger each time.

17. Red Diamond Rattlesnake

• Scientific Name: Crotalus ruber
• Habitat: Rocky, arid habitats of southwestern California and Baja California
• Size: 2 to 5 feet long
• Diet: Small mammals, lizards, birds

Red diamond rattlesnakes are typically calmer than other rattlesnakes, so it’s rare to hear their famous rattling sound. Their venom is also less potent than that of similar species, but one bite can still be fatal for humans without proper treatment. Their venom primarily harms the blood and blood vessels in a person’s body. When hunting, these snakes sit very still and wait for prey to come close before striking.

18. Red Fox

• Scientific Name: Vulpes vulpes
• Habitat: Woodlands and grasslands across most of the Northern Hemisphere
• Size: 7 to 31 pounds
• Diet: Small mammals, birds, eggs, amphibians, reptiles

Since red foxes have such a wide natural range, their appearance can vary. They vary in size and coat color. Many red foxes have the typical bright orange coat people are familiar with, while others have gray, dark brown, or even white fur. There are 45 distinct subspecies. These foxes have incredible sight and hearing, allowing them to instantly spot small prey from a distance. They can even hear animals digging deep underground.

19. Red Giant Flying Squirrel

• Scientific Name: Petaurista petaurista
• Habitat: Forests of Southeast Asia
• Size: 1 to 2 feet long (with tail)
• Diet: Pine cones, leaves, tree buds, fruits, nuts

These unique critters are much larger than the squirrels people usually see. They’re nocturnal and spend most of their time high in the trees alone. They can glide up to 250 feet, making it easy for them to get from one tree to the next. They nest in holes high up in trees. Rather than hibernating, they migrate to new areas when food is scarce.

20. Red Hartebeest

• Scientific Name: Alcelaphus buselaphus caama
• Habitat: Dry, arid areas of southwestern Africa
• Size: 250 to 265 pounds
• Diet: Grass

These majestic mammals live in herds of about 20 individuals. Usually, the groups are females and their young, one male and his mates, or males that are unable to maintain their own territory (such as those that are too young or too old). Males can be highly territorial, violently pushing each other with their horns to make their opponent lose their balance. They may also bounce over a foot off the ground when galloping to make themselves seem bigger and more intimidating to threats.

21. Red Panda

• Scientific Name: Ailurus fulgens
• Habitat: High-altitude forests with bamboo understories in the Eastern Himalayas
• Size: 8 to 14 pounds
• Diet: Bamboo, leaves, fruit, insects, bird eggs

Despite being called pandas, red pandas are more closely related to raccoons than giant pandas. In fact, red pandas got their names before giant pandas, and the large bears were named because they had similar markings and characteristics to these red mammals. Like giant pandas, red pandas primarily eat bamboo. They eat 20% to 30% of their body weight in bamboo daily. Even though they eat mostly plants, they’re descended from carnivores.

22. Red Paper Wasp

• Scientific Name: Polistes carolina
• Habitat: Dry locations on human structures across the eastern United States
• Size: 0.9 to 1.25 inches
• Diet: Nectar, insects, fruit juices

These red-orange insects build paper-like nests in any locations they can find, including porches, door frames, and roof overhangs. They can deliver painful stings to humans, which is why they’re considered pests in urban areas. The stings may have some swelling for a few hours, but the effects usually go away on their own unless you experience an allergic reaction.

23. Red River Hog

• Scientific Name: Potamochoerus porcus
• Habitat: Rainforests and near rivers of West and Central Africa
• Size: 100 to 270 pounds
• Diet: Roots, fruits, seeds, grasses, insects, eggs, carrion

Red river hogs stand out from other pigs because of their vibrant red-orange fur. They’re fast both on land and in the water. Like most hogs, they’re not picky when it comes to food. They will use their snouts to dig in the ground for food, and they will often follow other animals to pick up the food they drop. They mark their territory by scraping trees with their tusks and using their various scent glands. They will fight other animals if they feel their territory is threatened.

24. Red Ruffed Lemur

• Scientific Name: Varecia rubra
• Habitat: Rainforests of eastern Madagascar
• Size: 8 to 10 pounds
• Diet: Fruits, nectar, leaves, seeds, pollen

The majority of the red ruffed lemur’s diet is made up of fruits, especially figs. They love figs so much that they often fight over them. They have a unique set of six bottom teeth in the front of their mouth that act as a comb. They can use their tooth comb to groom themselves and remove skin from fruit. They also have a longer claw on the second toes of their back legs that can help brush their fur.

25. Red Spitting Cobra

• Scientific Name: Naja pallida
• Habitat: Dry savannas of East Africa
• Size: 2.5 to 4 feet long
• Diet: Amphibians, rodents, birds, small snakes

These venomous snakes can harm people with a regular bite, but they can also spray their toxins. They squeeze their muscles on their venom glands, which forces the toxins out through the fangs. They can spray the venom up to 8 feet, which can cause extreme pain and even blindness. They usually rear up and hiss to warn others, and if the threat doesn’t back off, that’s when they’ll resort to venom. They’re fast and alert, but they’re typically only active at night.

26. Red Squirrel

• Scientific Name: Sciurus vulgaris
• Habitat: Forests of the United States and Canada
• Size: 12 to 16 inches (with tail)
• Diet: Insects, seeds, nuts, bark, fruits

Even though they’re called red squirrels, they’re not always red. In the winter, they can have duller coloring, like brown and gray. They can usually be distinguished by their adorable ear tufts, but they may temporarily lose those tufts when molting. They don’t hibernate, which is why they store food for the winter like most squirrels. These rodents have an amazing sense of smell, allowing them to locate buried food, even if it’s under a foot of snow.

27. Red Triangle Slug

• Scientific Name: Triboniophorus graeffei
• Habitat: Woodlands on the east coast of Australia
• Size: About 6 inches
• Diet: Microscopic algae

Red triangle slugs come in a few different colors, such as white and beige, all of which have a red triangle shape on their backs. There’s a pore inside the triangle that they use for breathing. During the day, these slugs hide under leaf litter, but at night, they come out to feed. They graze on smooth-barked trees, eating algae that’s too small for the human eye to see.

28. Red-Backed Salamander

• Scientific Name: Plethodon cinereus
• Habitat: Moist forests of eastern North America
• Size: 2.2 to 3.9 inches (including tail)
• Diet: Insects, spiders, centipedes, earthworms, larvae

Red-backed salamanders are a species of lungless salamander, meaning they breathe through their skin and the lining of their mouths and throats rather than lungs. They can drop their tails if captured by a predator, and their tail will eventually grow back. Like other salamanders, they can also regenerate other body parts, including limbs and organs.

29. Red-Bellied Black Snake

• Scientific Name: Pseudechis porphyriacus
• Habitat: Moist areas of eastern Australia
• Size: 4.9 to 6.6 feet
• Diet: Slugs, worms, soft-bodied insects, small frogs

Rather than laying eggs like most snakes, red-bellied black snakes give birth to live young. This helps the young snakes thrive even in cooler temperatures. While these snakes look intimidating, they’re typically shy and only deliver serious bites when humans don’t leave them alone. They will often hide, rear up, hiss, and even pretend to strike before actually biting. They’re one of the least dangerous snakes of their size in Australia.

30. Red-Billed Gull

• Scientific Name: Chroicocephalus novaehollandiae scopulinus
• Habitat: Coastal areas of New Zealand
• Size: About 15 inches
• Diet: Fish, krill, worms, urban waste

Red-billed gulls have distinct bright red bills and feet, along with a red ring around each of their light yellow eyes. While they love to catch aquatic creatures for food, they will also scavenge, collecting food that humans leave behind. They’re usually monogamous, choosing one mate and staying with them for season after season. They build nests out of whatever plants they can find, including seaweed, grass, and leaves.

31. Red-Billed Quelea

• Scientific Name: Quelea quelea
• Habitat: Grasslands of Sub-Saharan Africa
• Size: About 5 inches long
• Diet: Grass seeds

Red-billed queleas are considered the most abundant wild birds in the world. There are currently about 1.5 billion of them. They create large flocks that can consist of millions of individuals. They typically have a thick red bill that’s great for picking up and crushing seeds. During the breeding season, they spend a lot of time creating nests by wrapping grass around twigs while building the structure.

32. Red-Crested Cardinal

• Scientific Name: Paroaria coronata
• Habitat: Semi-open areas of southeastern South America
• Size: About 7.5 inches
• Diet: Seeds, fruit, insects

While the famous northern cardinal is bright red all over, red-crested cardinals only have this bold coloring on their heads. They’re only native to South America, but they’ve been introduced to new areas, such as Puerto Rico and Hawaii. They typically live in small groups and pairs, often getting close to humans to search for food. During the mating season, males build the nests, but the females need to approve the structure before laying eggs.

33. Red-Crowned Crane

• Scientific Name: Grus japonensis
• Habitat: Wetland areas of eastern Asia
• Size: About 5 feet tall
• Diet: Insects, aquatic invertebrates, fish, amphibians, reeds, grasses

The red caps on these birds’ heads are actually exposed skin rather than bold feathers. The species is often viewed as a symbol of love and fidelity since they’re monogamous. When searching for a mate, they display beautiful dances that require them to leap, bounce, and stretch their wings. While doing this dance, the cranes communicate with each other using unique calls. They have different calls for distress and aggression.

34. Red-Crowned Roofed Turtle

• Scientific Name: Batagur kachuga
• Habitat: Freshwater rivers of India, Bangladesh, and Nepal
• Size: Up to 55 pounds
• Diet: Aquatic plants, fruits

From a distance, these turtles might not look super colorful, but if you get a closer look, you’ll see unique red and yellow coloring on their skin. They spend almost all their time in the water, but they’ll occasionally climb onto rocks and logs to bask in the sun. Sadly, these beautiful reptiles are critically endangered because of poaching and pollution.

35. Red-Eared Slider

• Scientific Name: Trachemys scripta elegans
• Habitat: Freshwater habitats across the United States
• Size: 5 to 11 inches
• Diet: Aquatic plants, small fish, worms, crustaceans, tadpoles

There are several North American turtles that look like red-eared sliders, but this species has distinct red patches on the sides of its head. They spend a lot of time swimming, but since they’re cold-blooded, they sometimes come to land to bask in the sun and regulate their temperatures. They often gather on logs to sunbathe in groups. While they can be kept as pets, domesticated red-eared sliders should never be released into the wild.

36. Red-Eyed Crocodile Skink

• Scientific Name: Tribolonotus gracilis
• Habitat: Tropical forests of New Guinea
• Size: 7 to 9 inches
• Diet: Insects, worms

Red-eyed crocodile skinks look like real-life baby dragons. They have very dark coloring everywhere except for the bright orange patches around their eyes. They’re shy and usually keep to themselves, causing them to hide in logs and leaf litter. They’re great climbers and swimmers, but they spend most of their time on the forest floor. When startled, they may play dead to get predators to leave them alone.

37. Red-Eyed Tree Frog

• Scientific Name: Agalychnis callidryas
• Habitat: Lowland tropical rainforests of southern Mexico and Central America
• Size: 2 to 3 inches
• Diet: Insects, worms, small frogs

Red-eyed tree frogs are some of the most iconic amphibians because of their bold blue, green, and orange coloring paired with bright red eyes. They have suction-like toes that allow them to quickly climb up trees. They can also jump over 20 times their body length to help them quickly escape predators. Also, their big red eyes are for more than just looks. When they blink, their eyes help them swallow faster, making it easy for them to eat one insect and quickly move on to their next prey.

38. Red-Faced Spider Monkey

• Scientific Name: Ateles paniscus
• Habitat: Rainforests of northern South America
• Size: 15 to 19 pounds
• Diet: Fruits, leaves, flowers, seeds, nuts, insects

Spider monkeys like this species can move so effortlessly in the trees because they have prehensile tails, meaning they can grab onto branches with their tails. Since they’re excellent climbers, they spend most of their time high in tree canopies. They’re social creatures that usually live in groups of up to 30 monkeys. The groups sleep near each other at night, but they sometimes break into smaller groups when foraging during the day.

39. Red-Footed Booby

• Scientific Name: Sula sula
• Habitat: Tropical and subtropical coastal areas across the Pacific, Atlantic, and Indian Oceans
• Size: 27 to 31 inches
• Diet: Fish, squid

Many people have heard of blue-footed boobies, and red-footed boobies are a very similar species. While they still have light blue bills, they have bold red feet instead of blue ones. They’re the smallest booby species, but they don’t let that slow them down. Since they always live near the ocean, they’re capable of traveling 90 miles while searching for food. They can quickly dive down into the water to capture their prey, but they may also snatch flying fish in mid-flight.

40. Red-Footed Tortoise

• Scientific Name: Chelonoidis carbonaria
• Habitat: Warm forests in South America and the Caribbean Islands
• Size: 11 to 14 inches
• Diet: Vegetables, fruit, carrion

These tortoises are named because of the red spots that appear on their legs. They sometimes have red or yellow spots on their faces as well. They’re the most active when the weather is warm, especially right after it rains. If it gets too cool, their metabolism slows down, helping them survive on very little food. Mature red-footed tortoises can go a whole month only eating a single banana if it’s cold enough.

41. Red-Handed Tamarin

• Scientific Name: Saguinus midas
• Habitat: Forests of Brazil, Guyana, French Guiana, and Suriname
• Size: 17 to 20 inches
• Diet: Fruits, insects, flowers, spiders, nectar

Red-handed tamarins are also called golden-handed tamarins since their feet typically look more gold than red. They usually live in small groups with anywhere from 2 to 12 individuals. The eldest female typically leads the group, and most of the other members are males. These primates are extremely agile, leaping up to 60 feet from trees to the ground without getting hurt.

42. Red-Headed Rock Agama

• Scientific Name: Agama agama
• Habitat: Deserts, savannas, forests, and mountains of Sub-Saharan Africa
• Size: 5 to 12 inches
• Diet: Insects

This agama species has unique coloring where the top half of its body is red and the bottom half is blue. They primarily live in hot environments where they bask in the sun and hunt for food during the day. They often form groups with one lead male and about six females. The lead male mates with several of the females in his territory. When the females lay eggs, the male agamas have a slightly different temperature than the females before they hatch.

43. Red-Headed Vulture

• Scientific Name: Sarcogyps calvus
• Habitat: Open habitats of northern India
• Size: 30 to 34 inches
• Diet: Carrion

These vultures have large bald patches on their heads, revealing bright red skin. Their red skin is also present on their necks, wattles, thighs, and legs. The main difference between males and females is their eye color. Females have white eyes while males have dark eyes. Unlike other vultures, these birds rarely gather in flocks to feed. Usually, only one or two red-headed vultures hover above the same carcass.

44. Red-Headed Woodpecker

• Scientific Name: Melanerpes erythrocephalus
• Habitat: Open woodlands of temperate North America
• Size: 7 to 10 inches
• Diet: Insects, spiders, worms, nuts, seeds, fruits

Like other woodpeckers, red-headed woodpeckers peck into wood to create cavities for shelter. While they may also do it to look for food, they primarily catch their insects in the air rather than digging them up. They’re one of the few woodpeckers that store food for later. They hide food in cracks of wood, both on trees and manmade structures, as a way to save it for later.

45. Red-Lipped Batfish

• Scientific Name: Ogcocephalus darwini
• Habitat: Sandy and rocky seabeds in the Pacific Ocean around the Galapagos Islands
• Size: 8 to 16 inches
• Diet: Small fish, shrimp, crabs, worms, mollusks

A red-lipped batfish’s lips are so bright that it looks like they’re wearing lipstick. They’re bottom-dwelling fish that appear anywhere from 10 to 250 feet below sea level. They have unique leg-like pectoral fins that allow them to “walk” along the ocean floor rather than swim. These unique fish have a small fleshy growth between their eyes that lights up to attract prey toward them.

46. Red-Necked Wallaby

• Scientific Name: Macropus rufogriseus
• Habitat: Grasslands and scrublands of eastern Australia
• Size: 30 to 41 pounds
• Diet: Grasses, roots, herbs, leaves

Red-necked wallabies are mostly brown, but the fur on their shoulders and the back of their necks usually has a red tint. They’re primarily solitary, but they may live near each other if an area has an abundance of resources for them. If they sense danger, they may stomp their feet on the ground to alert nearby wallabies. During dry seasons, they can go for a while without drinking water because the juicy roots they eat can keep them hydrated.

47. Red-Shanked Douc

• Scientific Name: Pygathrix nemaeus
• Habitat: Forests of Vietnam, Laos, and Cambodia
• Size: 15 to 25 pounds
• Diet: Leaves, fruits, seeds

Red-shanked doucs have bold, contrasting colors that make them look like paintings rather than real animals. They’re highly social, sometimes gathering in groups of up to 50. They use touch, vocalizations, and visual signals to communicate with others in the group. Group grooming is an important activity for them since it establishes strong bonds between all members.

48. Red-Shouldered Hawk

• Scientific Name: Buteo lineatus
• Habitat: Moist forests of eastern North America and coastal California
• Size: 15 to 25 inches long
• Diet: Small mammals, small birds, reptiles, amphibians, fish

Red-shouldered hawks are named for the red-orange patches on the tops of their wings, which stand out from their otherwise brown and white coloring. Their appearance may vary slightly depending on their location. For example, red-shouldered hawks living in Florida are often paler than those in northern states. They hunt a wide range of animals by perching somewhere and waiting for prey to approach before swooping down to capture it.

49. Red-Tailed Hawk

• Scientific Name: Buteo jamaicensis
• Habitat: Open woodlands across North America
• Size: 18 to 26 inches long
• Diet: Small mammals, birds, reptiles

Red-tailed hawks have a similar appearance to red-shouldered hawks, but they only have red-orange feathers on their tails. They’re the most common hawks in the United States, appearing in every state. They can fly 20 to 40 miles per hour, but they can reach speeds of up to 120 miles per hour when diving to capture prey. They make a majestic screeching sound that lasts for two to three seconds. This sound is often used as an eagle call in movies since it sounds more intimidating than real bald eagle calls.

50. Red-Tailed Monkey

• Scientific Name: Cercopithecus ascanius
• Habitat: Forests of Central Africa
• Size: 12 to 24 inches
• Diet: Fruits, leaves, flowers, insects

The long, red tails of these monkeys can be up to twice their body length. They cannot use their tails to grab things, but their tails can help them balance when climbing in tree canopies. These monkeys spend most of their time high in the trees, but they may occasionally come to the ground to forage. They can store food in their cheek pouches so they don’t have to make more than one trip to the ground at a time.

51. Red-Wattled Lapwing

• Scientific Name: Vanellus indicus
• Habitat: Open areas near water in West and South Asia
• Size: 12 to 14 inches
• Diet: Insects, snails, other invertebrates

Red-wattled lapwings are nicknamed “did-he-do-it birds” because that’s what they sound like they’re saying. They’re almost always near water, where they run in short bursts before quickly reaching down to grab prey. Sometimes, they move soil around with their feet to uncover invertebrates to snack on. They’re highly alert, noticing predators both day and night before the animals around them.

52. Red-Winged Blackbird

• Scientific Name: Agelaius phoeniceus
• Habitat: Marshes across North America
• Size: 7 to 9 inches
• Diet: Insects, grasses, weeds, grains

Red-winged blackbirds are commonly heard before they’re seen. They sit on high perches near water and let out a high-pitched “conk-la-ree” sound. The males have bold black feathers with a red patch on their wings, while females are brown. Males mate with several females each season, and all the females nest in the male’s territory. The males are highly territorial during the breeding season, swooping at other birds and even humans.

53. Redback Spider

• Scientific Name: Latrodectus hasselti
• Habitat: Dry, sheltered areas across Australia
• Size: 0.12 to 0.4 inches
• Diet: Insects, small vertebrates, other spiders

Redback spiders carry venom that can cause severe illness or even death. However, redback spider bites are uncommon since these arachnids rarely leave their web and have small jaws. They will eat almost any animals that get stuck in their webs, which could sometimes include animals larger than themselves, such as small mammals, lizards, and large spiders. Redback spiders sometimes even steal food from the webs of other spiders.

54. Reddish Egret

• Scientific Name: Egretta rufescens
• Habitat: Tropical swamps in coastal regions of Central America, Mexico, southern US, and nearby islands
• Size: 27 to 32 inches tall
• Diet: Small fish, frogs, tadpoles, crustaceans, aquatic insects

Reddish egrets look like they’re dancing when they’re actually hunting. They run, jump, and spin near shallow water to disturb the fish, making them easier to find. Even though they’re called reddish egrets, they have two unique color morphs. Many of them have reddish-brown feathers, but there’s also a rare, all-white morph. When mating, feather colors don’t seem to matter to these birds.

55. Redtail Catfish

• Scientific Name: Phractocephalus hemioliopterus
• Habitat: Freshwater habitats of the Amazon and Orinoco River basins
• Size: 3.5 to 5 feet
• Diet: Fish, crustaceans, fallen fruit

Like other catfish, redtail catfish have long whiskers that help them smell and taste, making it easier for them to navigate the world around them. Since water can sometimes get dark and murky, these whiskers guide them when they can’t see well. Redtail catfish are more active than similar species, chasing down prey rather than sitting and waiting to ambush prey. They mostly hunt at night and remain motionless during the day.

56. Reeve’s Muntjack

• Scientific Name: Muntiacus reevesi
• Habitat: Subtropical rainforests of southeastern China
• Size: 22 to 40 pounds
• Diet: Bamboo, seeds, bark, herbs, fungi, grasses, nuts

These unique mammals are a type of deer, sometimes called “barking deer” due to their unusual barking sounds. They typically bark to alert others of a threat, but they may also do it during the mating season. They’re one of the smallest deer species since they’re about as big as a medium-sized dog rather than a large deer. They eat a wide range of plants, and they use their long tongues to remove leaves from branches. Males have unique tusks that they can use to defend themselves from predators.

57. Regent Bowerbird

• Scientific Name: Sericulus chrysocephalus
• Habitat: Rainforests of eastern Australia
• Size: 10 to 12 inches
• Diet: Fruits, seeds, insects, spiders

Male regent bowerbirds build majestic bowers, much like other bowerbird species. Bowers are elaborate nest-like structures that are meant to attract females. Regent bowerbirds can create “saliva paint” to color their bowers a muddy blue or pea green hue. Male regent bowerbirds have bold black and yellow feather patterns while females have brown and white feathers.

58. Reindeer

• Scientific Name: Rangifer tarandus
• Habitat: Tundras, woodlands, and mountains in the Northern Hemisphere
• Size: 200 to 700 pounds
• Diet: Mosses, herbs, ferns, grasses, leaves

Reindeer are the same animals as caribou. Since they usually live in frigid temperatures, they’re covered in hair, including their noses and hooves, to keep warm. They eat a wide range of plants, often using their hooves to scrape snow away to access them. On average, adult reindeer eat between 9 and 18 pounds of vegetation daily. Both male and female reindeer grow antlers, which fall off and grow back each year.

59. Resplendent Quetzal

• Scientific Name: Pharomachrus mocinno
• Habitat: Cloud forests from southern Mexico to Panama
• Size: 14 to 16 inches
• Diet: Fruits, insects, small frogs, snails, lizards

This beautiful green and red bird is the national bird of Guatemala, appearing on the country’s flag. It was considered a sacred bird in Aztec and Mayan cultures, and the long tail feathers were a symbol of wealth. While killing quetzals was forbidden, people often caught them and removed their tail feathers. These birds have thin skin that can tear easily, so they evolved to have thick feathers to protect them.

60. Reticulated Giraffe

• Scientific Name: Giraffa reticulata
• Habitat: Open woodlands and savannas of Somalia, southern Ethiopia, and northern Kenya
• Size: 16 to 18 feet tall and 2,000 to 4,000 pounds
• Diet: Leaves, flowers, seed pods, fruits

Reticulated giraffes have large geometric patterns on their coat, which have less white space between them than the coat patterns of other giraffe species. These giraffes are massive, and their hearts can be up to 2 feet long, pumping up to 60 gallons of blood every 3 minutes. While giraffes are typically gentle creatures, they can use their forefeet to kick in self-defense. Since their necks are so long, they can easily see predators approaching and deliver a deadly kick if needed.

61. Reticulated Python

• Scientific Name: Malayopython reticulatus
• Habitat: Rainforests, woodlands, and grasslands of Southeast Asia
• Size: 5 to 22 feet long
• Diet: Mammals, birds

While the massive size of these snakes is intimidating, they’re not venomous. However, large reticulated pythons are capable of killing and eating a person. These snakes eat a wide range of mammals, including large creatures like pigs and primates. They capture prey by gripping onto it with their sharp teeth, and then they wrap their bodies around it to suffocate it before eating.

62. Rhim Gazelle

• Scientific Name: Gazella leptoceros
• Habitat: Across the Sahara Desert
• Size: 44 to 66 pounds
• Diet: Leaves, grasses, other desert vegetation

Rhim gazelles have a pale brown coat that resembles sand, allowing them to camouflage in desert settings. Because of this, they’re sometimes called sand gazelles. Their light coat color can also reflect the sun, reducing the risk of overheating. While they have skinny legs, their hooves are wide to make traveling across the sand easy. They rarely need to drink water since they can collect enough moisture from the plants they consume.

63. Rhinoceros Auklet

• Scientific Name: Cerorhinca monocerata
• Habitat: Open water of the Pacific Ocean
• Size: 14.5 to 15.5 inches
• Diet: Small fish, zooplankton

These birds spend most of their time in the open ocean, only returning to land to breed. They float on the water but quickly dive down to capture prey. They have unique spikes on the back of their upper jaw to help them cling to slippery prey. The purpose of the unique horn on this species’ bill has been a mystery for a long time, but researchers recently learned that it appears brightly colored to other animals. So, it might help these auklets see each other underwater.

64. Rhinoceros Hornbill

• Scientific Name: Buceros rhinoceros
• Habitat: Tropica forests of Southeast Asia
• Size: 37 to 42 inches
• Diet: Fruits, eggs, bugs, small reptiles, frogs

Rhinoceros hornbills have a unique horn on top of their bills, known as a casque. Casques are hollow inside, allowing them to help the birds’ calls reach further distances. They may provide foraging benefits as well. The casque is white when these birds are born, but it becomes orange and red at around six years old. Both males and females have this unique bill shape, but males have bright red eyes while females have white or very light blue eyes.

65. Rhinoceros Iguana

• Scientific Name: Cyclura cornuta
• Habitat: Dry, rocky areas of the Caribbean island of Hispaniola
• Size: 2 to 4.5 feet
• Diet: Leaves, shrubs, flowers, fruit

Male rhinoceros iguanas have a small horn on their nose. Those horns may help attract mates, but they don’t seem to serve any other significant purpose. When attracting females, the males bob their heads to show off their horns while also raising the spines on their backs. While they’re typically shy and skittish, they may act aggressively and attack if they feel threatened.

66. Rhinoceros Ratsnake

• Scientific Name: Gonyosoma boulengeri
• Habitat: Subtropical rainforests from northern Vietnam to southern China
• Size: 3.5 to 5.5 feet long
• Diet: Small rodents, birds, and bird eggs

Rhinoceros ratsnakes have bright green scales and a pointed nose that looks like a horn. On rare occasions, they will keep their juvenile coloring, making them look gray. They spend almost all their time in the trees. If they feel threatened, they can inflate part of their body to intimidate predators. Even though they’re not venomous, they may bite if they feel threatened.

67. Ribbon Eel

• Scientific Name: Rhinomuraena quaesita
• Habitat: Tropical waters of the Indian and Pacific Oceans
• Size: 2 to 4.5 feet long
• Diet: Small fish, crustaceans

Ribbon eels are unique creatures that go through a major color change as they age. Juveniles are pitch black with a yellow dorsal fin, while adults are mostly yellow (female) or mostly blue with some yellow (male). They’re able to change between male and female, which causes their coloring to change too. These eels have long nostrils that help them sense vibrations, and their mouths open and close frequently because that’s how they breathe.

68. Ribbon-Tailed Astrapia

• Scientific Name: Astrapia mayeri
• Habitat: Montane forests of Papua New Guinea
• Size: About 1 foot long
• Diet: Fruit, insects, spiders, frogs

Ribbon-tailed astrapias are fairly small, but they look bigger than they are because the males have flowing tail feathers that are often about three times their body length. While males and females both have shimmering blue feathers, females are typically duller than males. Males raise their ribbon-like tail feathers and hop between branches to attract females. The males mate with several females at a time.

69. Ring-Billed Gull

• Scientific Name: Larus delawarensis
• Habitat: Near bodies of water across North America
• Size: 17 to 21 inches
• Diet: Insects, fish, worms, garbage, grains, rodents

Ring-billed gulls aren’t scared of humans, so they may flock in shopping centers and parks to pick up the food people drop. Sometimes hundreds of them flock together. Many gulls display these behaviors, so to tell this species apart, look for a distinct dark ring on their yellow bills. These birds have a built-in compass that allows them to find their way when flying. Most of these birds return to where they were born each year to lay their own eggs.

70. Ring-Necked Snake

• Scientific Name: Diadophis punctatus
• Habitat: Moist woodlands across North America
• Size: 9 to 15 inches long
• Diet: Small salamanders, worms, slugs

Ring-necked snakes have a unique defense mechanism that involves flipping over their belly and wrapping their tail around themselves to reveal bright orange coloring. This behavior has earned them the nickname “corkscrew” and “thimble” snakes. While they’re venomous to the small prey they catch, they’re generally harmless to humans due to how tiny they are. Their coloring convinces predators that they’re more dangerous than they are.

71. Ring-Tailed Lemur

• Scientific Name: Lemur catta
• Habitat: Forests of southern Madagascar
• Size: 15 to 18 inches
• Diet: Leaves, flowers, insects

Ring-tailed lemurs have long black-and-white tails that can be twice as long as their bodies. These long tails help them balance, but they also help lemurs locate each other since the tails can be raised above tall grass. Male ring-tailed lemurs may also put their scent on their tails and wave them around to intimidate threats. These mammals typically live in social groups that range from 3 to 25 individuals. Females are dominant in these groups.

72. Ring-Tailed Vontsira

• Scientific Name: Galidia elegans
• Habitat: Humid forests of Madagascar
• Size: 12.5 to 15 inches
• Diet: Small mammals, invertebrates, fish, eggs, fruit

Ring-tailed vontsiras look like lemurs and inhabit the same island, but they’re actually a type of mongoose. They sometimes even feed on small lemurs. They’re agile little creatures, capable of climbing and swimming effortlessly. They’re primarily active during the day, where they often run around and play with each other. At night, they retreat to tree crevices or burrows to rest.

73. Ringed Kingfisher

• Scientific Name: Megaceryle torquata
• Habitat: Near rivers and lakes from Mexico through South America
• Size: 11 to 14 inches
• Diet: Fish, crustaceans

The narrow, pointed bill of the ringed kingfisher is perfect for quickly snatching fish and other aquatic prey out of the water. Their bills have jagged edges to ensure slippery fish don’t escape. They frequently perch above water and watch for fish before striking. Most of their prey is scooped from shallow water that’s within three feet of the shore. In rare cases, they may forage in the water for food, too.

74. Ringed Seal

• Scientific Name: Pusa hispida
• Habitat: Arctic waters of the northern Pacific Ocean
• Size: 70 to 270 pounds
• Diet: Fish, crustaceans, cephalopods

Ringed seals spend most of their time under solid ice, creating breathing holes with their claws. They may also set up snow caves known as lairs to rest. These seals usually travel solo, swimming 6 miles per hour on average (but they’re capable of reaching 19 miles per hour). These aquatic mammals are frequently preyed upon by larger animals, such as polar bears, walruses, and orcas.

75. Risso’s Dolphin

• Scientific Name: Grampus griseus
• Habitat: Mid-temperature waters across the Pacific, Atlantic, and Indian Oceans
• Size: 660 to 1,100 pounds
• Diet: Fish, cephalopods, krill

Risso’s dolphins usually have lots of scars across their body, making a unique pattern of light and dark markings. These scars come from fellow dolphins or prey fighting back, such as squids. The scars have no pigment when they heal, which is why they stand out so much. While most of this dolphin’s prey can be caught during brief dives, they’re capable of diving 1,000 feet below the surface and holding their breath for half an hour if needed.

76. Riverine Rabbit

• Scientific Name: Bunolagus monticularis
• Habitat: Dense vegetation near rivers in South Africa
• Size: 13.5 to 18.5 inches
• Diet: Leaves, flower petals, grass

Riverine rabbits are wild rabbits that have larger ears and longer bodies than most rabbits. They’re one of the rarest mammals in the world, with less than 200 mature individuals remaining. They’re also solitary and nocturnal, so they’re rarely seen and observed. The male riverine rabbits mate with several females each season, and each female has one offspring that she cares for in underground burrows.

77. Rock Bass

• Scientific Name: Ambloplites rupestris
• Habitat: Clear, rocky streams of eastern North America
• Size: 6 to 10 inches
• Diet: Crayfish, small fish, aquatic insect larvae

Rock bass have large mouths and red eyes, but their overall coloring isn’t consistent. These fish can change colors slightly to help them better blend in with their surroundings. Their colors may also shift due to age and stress. These fish can have patterns of brown, yellow, green, silver, and black on their scales. They’re commonly caught by fishermen in river drainages.

78. Rock Hyrax

• Scientific Name: Procavia capensis
• Habitat: Rocky, scrub-covered areas of Africa and the Middle East
• Size: 12 to 22 inches
• Diet: Grasses, leaves, fruits, insects, grubs

Rock hyraxes have two upper incisors that continuously grow to make up for the teeth wearing down. Sometimes, these teeth grow so long that they look like tusks. Even though they resemble rodents, they’re actually close relatives of elephants. Yet, the two species are so drastically different because they diverged from each other over 60 million years ago. Rock hyraxes almost always urinate in the same spots, which causes the rocks beneath them to turn white.

79. Rock Monitor

• Scientific Name: Varanus albigularis
• Habitat: Dry habitats across parts of Africa
• Size: 3 to 5 feet long
• Diet: Large insects, small lizards

Rock monitors are intelligent reptiles. Studies found that they can count up to six and determine when an object is missing from a group. In the wild, they spend most of their time in tunnels that they dig or ones abandoned by other animals. They’re not picky when it comes to prey. If they don’t find their preferred diet, they may scavenge corpses or go after large prey by tearing it apart.

80. Roe Deer

• Scientific Name: Capreolus capreolus
• Habitat: Woodlands across areas of Europe and Asia
• Size: 35 to 75 pounds
• Diet: Leaves, tree shoots, herbs, brambles, ivy, grass

Roe deer have a distinct reddish-brown coat in the summer, but it eventually fades to gray-brown in the winter. They often gather in groups when it’s warm out, but in the winter, they normally only stick with their mate and offspring. When startled, these deer may make a barking sound like a dog. They also use other sounds to communicate with each other, such as warning grunts from males or high-pitched whines from females to attract mates.

81. Roosevelt Elk

• Scientific Name: Cervus canadensis roosevelti
• Habitat: Forests and mountains of the Pacific Northwest
• Size: 600 to 1,100 pounds
• Diet: Grasses, shrubs, flowers, ferns, lichens

A conservationist named the Roosevelt elk after President Theodore Roosevelt in 1897 because he set aside land to protect and preserve these elk. They’re the largest of the six subspecies of the North American elk. These mammals split into several groups, with adult males living together while females stick together with their calves. Both males and females have a unique call known as “bugling,” which sounds like a roar mixed with a whistle.

82. Rose-Breasted Grosbeak

• Scientific Name: Pheucticus ludovicianus
• Habitat: Open deciduous forests across North America and northern South America
• Size: 7.1 to 8.7 inches
• Diet: Insects, seeds, berries

Rose-breasted grosbeaks are named after the red patches that males have under their necks. Males are black and white everywhere else, while females have brown patterns. These birds build flimsy nests, causing the eggs to sometimes be visible through the bottom of the nests. Males and females take turns incubating the eggs. In some areas, rose-breasted grosbeaks could mate with black-headed grosbeaks, causing offspring that could look like either species.

83. Rose-Ringed Parakeet

• Scientific Name: Psittacula krameri
• Habitat: Forests, savannas, and grasslands across Africa and South Asia
• Size: About 16 inches
• Diet: Fruits, vegetables, buds, nuts, seeds

Rose-ringed parakeets are mostly green, but they have a light pink ring around their necks. These birds visit a wide range of habitats, including farmlands, where they’re considered pests for causing damage to crops. These beautiful birds are sometimes kept as pets because they’re very intelligent and can learn to mimic human speech. A rose-ringed parakeet is capable of learning up to 200 human words and phrases.

84. Roseate Spoonbill

• Scientific Name: Platalea ajaja
• Habitat: Coastal regions of South America and southern North America
• Size: About 2.5 feet tall
• Diet: Crustaceans, aquatic insects, small fish

The roseate spoonbill has beautiful pink feathers, and like flamingos, that coloring comes from the foods they eat. These stunning birds usually stay with the same mate for life, and they work together to care for their young. When trying to attract a mate, they present sticks to each other as gifts. As they age, they lose feathers on their heads, causing them to go bald.

85. Rosy Boa

• Scientific Name: Lichanura orcutti
• Habitat: Rocky deserts of California, Arizona, and Baja California
• Size: 17 to 34 inches
• Diet: Small mammals, birds, lizards

Rosy boas are fairly docile, acting non-confrontationally when faced with a threat. While their bites can still hurt, they aren’t venomous. Since they’re not very dangerous to humans, they’re often kept as pets. They’re one of the smallest and slowest constrictors, only moving about one mile per hour. They sometimes move more like an inchworm or caterpillar, making their slithering less seamless than other snakes.

86. Rosy-Faced Lovebird

• Scientific Name: Agapornis roseicollis
• Habitat: Dry, open country of southwestern Africa
• Size: 6.7 to 7.1 inches
• Diet: Seeds, flowers, berries, leaves, buds

Rosy-faced lovebirds are small green birds with pink around their faces as if they’re blushing. They’re social birds that almost always appear in flocks, small groups, or pairs. They can be noisy, using loud shrieking calls to communicate with each other. Living up to the name lovebird, these birds form monogamous, long-lasting pairs.

87. Rough Green Snake

• Scientific Name: Opheodrys aestivus
• Habitat: Moist habitats of the southeastern United States
• Size: 20 to 40 inches long
• Diet: Insects, snails, spiders, small frogs

These snakes have rough-looking green scales, hence the name. They can live anywhere that’s moist with dense vegetation, which could even include backyards. However, they spend as much time in the tree canopies as possible. They’re mostly active during the day, and they hibernate during winter. They’re docile, non-venomous, and rarely bite, so there’s no need to panic if you see one.

88. Rough-Legged Buzzard

• Scientific Name: Buteo lagopus
• Habitat: Tundra and taiga habitats across the Northern Hemisphere
• Size: 18 to 27 inches
• Diet: Small mammals

Rough-legged buzzards feed almost solely on small mammals. Their preferred prey includes lemmings and voles, which make up 80 to 90% of their diet. They hunt these critters by watching from perches and searching for them in mid-flight. They sometimes even steal prey from other birds. Outside of the breeding season, these majestic birds are almost always solitary.

89. Rough-Skinned Newt

• Scientific Name: Taricha granulosa
• Habitat: Ponds, wetlands, and creeks of the Pacific Northwest
• Size: 4.3 to 7 inches
• Diet: Insects, worms, spiders, aquatic invertebrates

While most amphibians have smooth, slimy skin, rough-skinned newts are bumpy. Those bumps can release poisonous neurotoxins in self-defense. The toxins are meant to hurt predators, so luckily, they don’t cause much harm to human skin besides some minor irritation. Rough-skinned newts have a bright orange belly and a foul smell to warn predators to stay away.

90. Rough-Toothed Dolphin

• Scientific Name: Steno bredanensis
• Habitat: Oceanic waters of tropical and warm temperate regions of the world
• Size: 200 to 350 pounds
• Diet: Large fish, cephalopods

Rough-toothed dolphins are smaller than most dolphin species. They travel in groups of 20 to 30 individuals. If there’s a calf in the group, the mom will make sure the calf stays between her and another dolphin at all times. These dolphins can dive over 100 feet below the water’s surface, and they can hold their breath for 15 minutes at a time. They sometimes have white bite marks and scars on their skin from incidents with sharks.

91. Royal Penguin

• Scientific Name: Eudyptes schlegeli
• Habitat: Rocky areas of Macquarie Island and nearby islands
• Size: 26 to 30 inches
• Diet: Small fish, crustaceans, squid, krill

Royal penguins have bold yellow feathers on their heads that sometimes stick up like a crown. These penguins lay two eggs, but only one usually survives. The second egg is typically larger and hatches first, causing it to produce a stronger chick than the other egg. The smaller chick is usually kicked out of the nest, but it’s unclear why. The penguins often leave their native island during the breeding season, but researchers aren’t sure where they go.

92. Rubber Boa

• Scientific Name: Charina bottae
• Habitat: Woodlands and grasslands of the western United States and British Columbia, Canada
• Size: 15 to 28 inches long
• Diet: Rodents, small reptiles, eggs, birds

A rubber boa’s skin is loose, smooth, and shiny, making it look like it’s made of rubber. They’re adaptable to a wide range of environments due to their ability to climb, burrow, and swim. They spend a lot of time hiding under objects like leaf litter, logs, and rocks, and they’re most active at night. Since they live in temperate regions, they hibernate in the winter.

93. Ruby-Crowned Kinglet

• Scientific Name: Regulus calendula
• Habitat: Dense conifer forests across North America
• Size: 3.5 to 4.3 inches
• Diet: Insects, spiders

Ruby-crowned kinglets might be tiny, but they lay large egg clutches of about 12 eggs. They move around frantically when foraging for food, making them seem nervous. They flick their wings almost constantly, making it easy to spot them among similar species. Males have a bright red patch on their heads, but it remains hidden most of the time. When males become excited or agitated, they will raise their feathers to show off the bright red hue.

94. Ruby-Throated Hummingbird

• Scientific Name: Archilochus colubris
• Habitat: Open woodlands, parks, and gardens of eastern North America
• Size: 2.8 to 3.5 inches
• Diet: Nectar, insects, spiders

Ruby-throated hummingbirds are one of the most recognizable hummingbird species because their bright red throats stand out from their otherwise green bodies. They can beat their wings over 50 times per second, making it easy for them to hover near flowers as they collect nectar. They can even fly backwards. If you listen closely, their wings sound like they’re making a humming sound, which is where the term hummingbird came from.

95. Ruddy Duck

• Scientific Name: Oxyura jamaicensis
• Habitat: Lakes, rivers, and wetlands across North and South America
• Size: 14 to 17 inches
• Diet: Aquatic invertebrates

Male ruddy ducks have a distinct appearance with a light blue bill and a spiky black tail. They show off their bills to females by hitting their bills against their necks and creating bubbles in the water. During the breeding season, male ruddy ducks become aggressive, chasing off other ducks and even animals on the shore. They feed by diving underwater and grabbing food from the bottom of lakes and rivers.

96. Ruddy Turnstone

• Scientific Name: Arenaria interpres
• Habitat: Open tundra and rocky shores of all continents
• Size: 8.7 to 9.4 inches
• Diet: Insects, crustaceans, mollusks

Ruddy turnstones have a very wide range. They breed in the high Arctic tundra of North America and Eurasia, and then they fly to the coasts of North America, South America, Eurasia, Africa, and Australia in the winter. They can fly 27 to 47 miles per hour, allowing them to migrate long distances. These birds have unique feet with sharply curved toenails to help them grip various surfaces, including slippery rocks.

97. Ruffed Grouse

• Scientific Name: Bonasa umbellus
• Habitat: Forests and woodlands across Canada and the northern United States
• Size: 16 to 20 inches
• Diet: Leaves, fruits, buds, insects

Ruffed grouse have a diverse diet that consists of various plants. If they can’t find their preferred foods, they can safely digest plants that would be bitter and toxic to other birds. Their unique digestive system also allows them to consume large amounts of fibrous vegetation, helping them stay strong in the winter. Their feet feathers grow longer in the winter to act as snowshoes, and they often burrow in snow drifts to protect themselves from chilling winds.

98. Rufous Hornbill

• Scientific Name: Buceros hydrocorax
• Habitat: Forests of the Philippines
• Size: 24 to 35 inches
• Diet: Fruits, seeds, insects, centipedes

Rufous hornbills have stunning coloring with a light brown neck, back feathers, and a large red bill. They make loud booming calls almost every hour, causing Philippine residents to nickname them “the clock of the mountains.” They’re also noisy when flying because their large wings make a whirring sound as they move. During the breeding season, the females spend almost all their time in a nest cavity with their young, much like other hornbill species do.

99. Rüppell’s Fox

• Scientific Name: Vulpes rueppellii
• Habitat: Deserts of North Africa
• Size: 26 to 29 inches
• Diet: Insects, small mammals, lizards, birds, grasses, succulents, fruits

These small foxes are sometimes confused with fennec foxes, but fennec foxes are much smaller. Rüppell’s foxes mate for life, and each pair has its own territory. They use scent glands to mark their territory, especially the area near their den. They can also spray predators with those glands, making it easier for them to escape. To communicate with each other, they use a variety of vocalizations, such as barks, hisses, trills, and whistles.

100. Rüppell’s Vulture

• Scientific Name: Gyps rueppellii
• Habitat: Grasslands and woodlands of Sub-Saharan Africa
• Size: 3 feet tall with an 8-foot wingspan
• Diet: Carrion

These large vultures can fly higher than almost any other bird species. One Rüppell’s vulture was documented flying over 36,000 feet above sea level. Sadly, this was discovered because a vulture got stuck in an aircraft’s engine. It’s believed that this species adapted to have altered proteins, allowing the bird to survive while flying among low pressure and low oxygen. These birds spend most of their time in the air, searching for dead animals to feed on.

101. Russell’s Viper

• Scientific Name: Daboia russelii
• Habitat: Open, grassy areas of the Indian subcontinent
• Size: 4 to 5 feet long
• Diet: Rodents, small reptiles, scorpions, land crabs

The Russell’s viper is one of the most dangerous snakes in India. They’re venomous and highly aggressive, sometimes chasing humans who agitate them. Their fangs are over half an inch long, causing the bite to be painful in addition to the venom’s danger. In Tamil Nadu, India, there are about 10,000 deaths annually due to this snake bite, and it’s not the only state in India affected by this snake. When hunting, Russell’s vipers use heat-sensitive organs to help them locate prey.

102. Russian Tortoise

• Scientific Name: Testudo horsfieldii
• Habitat: Open, arid environments of Central Asia
• Size: 5 to 8 inches long
• Diet: Grasses, leaves, flowers, weeds

While there are lots of wild Russian tortoises across Asia, they’re also one of the most common pet tortoises due to their small size and docile nature. However, they still live 40 to 60 years, sometimes even reaching 100. In the wild, Russian tortoises are inactive more often than not. They hibernate in the winter, and during the intense summer heat, they go into a state of dormancy. In between these periods, they spend as much time foraging as possible, and they often dig burrows.

103. Rusty Blackbird

• Scientific Name: Euphagus carolinus
• Habitat: Wooded swamps across Canada and the eastern United States
• Size: 8 to 10 inches
• Diet: Insects, plant matter, snails, crustaceans, small fish, small salamanders

Most of the time, rusty blackbirds look like blackbirds that are rusting because of orange spots that appear on their black feathers. Females have more rusty-colored feathers than males, and during the breeding season, males have pure black coloring. Scientists noticed that this bird’s population has declined by 85 to 99% in the past 40 years, but the cause of this drastic change is unknown.

More Animals (A-Z)

This might seem like a long list of animals, but it’s only the beginning. Not only are there more animal species starting with R, but there are tons of animals under every other letter of the alphabet, too. If you want to learn more about unique animal species, see what critters appear under the other letters.

A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z