15 Rhinoceros Facts About The Endangered Giants

Rhinoceros are one of the biggest and toughest land animals. They have of their thick skin and massive horns found on their noses. However, though they have no natural predators, some rhino species are on the brink of extinction. By reading through these rhinoceros facts, you'll discover what sets them apart from other big animal species, their biggest threats, and the conservative efforts that protect them.

Related read: Be acquainted with other African wonders with our giraffe facts and zebra facts.

15 Facts About Rhinos

1. There are five rhino species.

Did you know that there are five species of rhino? There are two African rhino species (white and black rhinos), and the remaining are Asian rhino species (Indian, Sumatran, and Javan).

• White Rhinoceros (Ceratotherium simum): White rhinos are the largest rhino species, with two horns, the front one usually longer. They live in southern Africa, mainly South Africa, Namibia, Zimbabwe, and Kenya.
• Black Rhinoceros (Diceros bicornis): Black rhinos have pointed upper lips and two horns. They are more solitary and aggressive behavior compared to the white rhino. Historically, black rhino populations ranged across much of sub-Saharan Africa. Still, due to poaching and habitat loss, their numbers have drastically declined, and they are now mainly found in eastern and southern Africa.
• Indian Rhinoceros (Rhinoceros unicornis): The Indian rhinos, or greater one-horned rhinos, are the second-largest rhino species and have a single horn. They live in grasslands and swamps in Nepal and northeastern India.
• Sumatran Rhinoceros (Dicerorhinus sumatrensis): The Sumatran rhino is the smallest and most critically endangered rhino species. They have thick, reddish-brown hair and two horns. Their populations scatter across fragmented forests in Indonesia (Sumatra and Borneo) and Malaysia.
• Javan Rhinoceros (Rhinoceros sondaicus): The Javan rhino is the world's most critically endangered mammal and has a single horn, typically shorter than the Indian rhino's horn. Javan rhinos are found only on the island of Java in Indonesia (specifically in Ujung Kulon National Park), with a tiny population also existing in Vietnam's Cat Tien National Park.

2. Rhinos are the heaviest land animal, second only to elephants.

Rhinos rank second as the largest and heaviest terrestrial animal. The white rhino tips the scales at 5,000 pounds. The smallest rhino species is still significantly large and weighs around 1,870 pounds.

Related read: Check our elephant facts next.

3. White Rhinos and Black Rhinos are gray.

Though confusing, the names of white and black rhinos don't reflect their actual color. The 'White Rhino' name resulted from a quirky misunderstanding by early English settlers in South Africa. They misheard the Afrikaans' wyd' (meaning 'wide') as 'white' when referring to the animal. However, 'wyd' actually referred to the rhino's wide, flat mouth.

Meanwhile, the 'Black Rhino' received its name as a simple contrast to the 'White Rhino,' not because of color differences. Some speculate that this may be due to their tendency to roll in mineral-rich mud, making their skin appear darker.

4. Their horns are their most prominent feature.

Our next rhinoceros fact talks about the animal’s name origin.

The term "rhinoceros" originates from two Greek words: "rhinos," meaning "nose," and "keras," meaning "horn." These animals have a prominent horn on their nose, which gives them their name. However, these horns aren't just decorative; they serve as the rhino's first line of defense. Black, white, and Sumatran rhinoceroses have two horns, with the larger one being called the anterior horn, and can grow up to 59 inches.

The posterior horn is shorter and can grow up to 22 inches. Besides self-defense, rhino horns are also for practical purposes such as digging for water and breaking branches². Indian and Javan rhinos use their single horns in the same way.

5. Despite their size, they are herbivores.

Though rhinos are overwhelmingly big, they are proud herbivores³. These giants live in habitats that offer vast vegetation like forests, savannas, grasslands, and floodplains of Africa and Asia. Specific diets vary across species. White rhinos are grazers, relying mainly on grasses in savannas and grasslands. With their wide lips, they are well-suited for grazing on short grasses.

On the other hand, Black rhinos are browsers, preferring leaves, shoots, and branches of trees and shrubs in savannas and woodlands. Their pointed upper lip enables them to be highly selective in food choices. Indian rhinos have a more diverse diet than African rhinos (black and white rhinos). They eat various plants, fruits, and aquatic vegetation.

Sumatran rhinos are also browsers, feeding on a wide range of vegetation in dense forest habitats, including leaves, fruits, twigs, and bark. Lastly, Javan rhinos, found in the tropical rainforests of Java, are mainly browsers, consuming leaves, fruits, shoots, and other low-growing vegetation. Due to their critically endangered status and limited distribution, limited information is available on their specific dietary preferences.

6. The Indian Rhino is a great swimmer.

You read that right. The Indian Rhino is semi-aquatic and a gifted swimmer. They thrive in habitats near water sources, such as marshlands, grasslands, and alluvial floodplain forests. The Indian Rhino uses water as a defense mechanism to escape potential threats. Swimming also allows them to move between different areas and access abundant vegetation, including aquatic plants, reeds, and grasses growing near the water.

Related read: Learn more about another swimming giant with our hippopotamus facts.

7. They use mud as sunscreen and bug repellant.

These adorable giants are intelligent and resourceful. When it gets too hot, rhinos dip in muddy puddles to cool their bodies. Once the mud dries, it acts as a natural sunscreen. African savannas can reach 30 degrees Celsius during summer, which is quite hot. Unlike their peers, rhinos don't have fur or feathers to protect them from the scorching heat. They must utilize whatever is available to adapt.

However, it doesn't end there. They also cover themselves with mud to drive away flies, parasites, and bugs. Genius!

8. They love to nap.

You might often find rhinos taking their afternoon nap under a tree. They're not slacking off, trust me. This siesta is a significant part of their daily routine, a much-needed break during the intense afternoon heat. Napping is an effective way of conserving energy. They are most active at dawn and dusk, keeping their afternoons free for that all-important power nap.

Aside from their horns, the rhinoceros fact below talks about another prominent feature of these animals.

9. They have thick skin.

Their skin is thick (up to two inches) and wrinkly. It acts as a natural armor against threats, shielding them from thorny bushes, rough branches, and the scorching sun. Furthermore, the folds on rhino skin aid in thermoregulation and easy mobility.

So what made their skin thick? The thickness of rhino skin results from a dense layer of collagen fibers. Collagen is a fibrous protein that provides structural support and strength to various tissues in the body. In rhinos, this collagen layer is particularly well-developed, offering robust protection against physical impacts and external injuries. 

Another contributing factor is the presence of a thick layer of subcutaneous fat. This layer acts as insulation and further enhances the skin's durability. However, it's important to note that though thick, their skin is extremely sensitive. That's why they use their mud sunscreen.

10. They can sense other rhinos through poop.

Did you know that rhinos use their poop to communicate important information¹? The distinctive scent in their feces contains chemical signals that convey their sex, age, reproductive status, and territorial boundaries. When one rhino encounters these scent markings, it can learn crucial details about the other rhino, helping it to assess potential mates or rivals and avoid unnecessary conflicts.

In addition, rhinos also use vocalizations, body language, and physical interactions to communicate with each other. Grunts, snorts, and trumpeting vocalizations serve various social purposes, including mating displays, warning signals, and expressions of distress. Physical interactions, such as headbutting and body leaning, also help rhinos establish dominance, hierarchies, and social bonds within their community.

11. Female rhinos have a long gestation period.

Rhinos have one of the longest gestation periods in mammals. They give birth to their calf after 15 to 16 months. The reason? This extended period is likely because they carry a much larger baby that requires more time and energy to develop. A newborn rhino calf can weigh between 88 to 140 pounds. Typically, rhino babies stay with their mothers for up to three years.

12. Wild rhinos live around 40-50 years.

Their tenacity allows them to see decades, living an average of 40 to 50 years. This is even true in harsh conditions where these sturdy creatures face intense heat, droughts, and fluctuating food supply. Evolution has gifted them with adaptable digestive systems, letting them make do with dry grass and shrubs during lean times.

Then there are our captive rhinos. Here, they find themselves tucked away from danger, living under the vigilant eyes of caretakers. In zoos and sanctuaries, rhinos live even longer, reaching up to 60 years. Regular meals, clean water, and timely medical intervention are pivotal in extending their lifespan. Yet, while their days may be longer, it's crucial to remember that the safety of captivity can never substitute the vibrancy and diversity of life in the wild.

13. African rhinos are friends with oxpeckers.

Did you know that African rhinos have a unique relationship with oxpeckers? These birds, sometimes called "tick birds" or "cleaner birds," are helpful companions to rhinos by providing grooming services. They eat ticks, parasites, and insects that infest rhino skin.

Additionally, oxpeckers serve as guards for rhinos, warning them of danger with their sounds since rhinos have poor eyesight. In exchange for their services, rhinos offer oxpeckers a reliable food source and a safe place to perch⁴.

14. Three subspecies are already extinct.

Three subspecies of modern rhinos have tragically become extinct due to different threats.

• Western Black Rhino (Diceros bicornis longipes): It was declared extinct in 2011 by IUCN. The primary reason for its extinction was rampant poaching for its valuable horn. Loss of habitat due to human encroachment and conflict with humans also contributed to its decline.
• Northern White Rhino (Ceratotherium simum cottoni): The last male of this subspecies died in 2018, leaving only two surviving females, making it functionally extinct. Poaching for their horns decimated their population.
• Vietnamese Javan Rhino (Rhinoceros sondaicus annamiticus) became extinct in 2011. The primary cause of its extinction was also poaching for its rhino horn, driven by the demand for traditional medicine and illegal wildlife trade. This subspecies was restricted to the Cat Tien National Park in Vietnam, making it one of the world's rarest and most critically endangered mammals.

15. Poaching is their greatest threat.

In the early 1900s, there were approximately 500,000 rhinos found in Africa and Asia. However, by 1970, the rhino numbers dropped to 70,000. Unfortunately, today there are only around 27,000 remaining rhinos in the wild. Rhino poaching remains their most significant threat. Poachers target their valuable horns, which are highly sought-after trophies in the illegal wildlife trade and traditional Asian medicine markets.

Poachers relentlessly hunt and kill rhinos, pushing several rhino species to extinction. To make matters worse, the increasing human populations also contribute to habitat loss for these animals. Climate change is intensifying drought and affecting vegetation, further compounding the challenges rhinos face.

IUCN lists the three species of rhino—black, Javan, and Sumatran—as critically endangered species. The white rhino (Ceratotherium simum) is listed as near threatened, with an estimated population of around 18,000. Despite being listed as vulnerable, the Greater One-Horned Rhino (Rhinoceros unicornis) has one of Asia's most successful conservation stories. Thanks to the conservation efforts of Indian and Nepalese authorities, their population has significantly increased.

Conservation efforts to protect rhinos include anti-poaching measures, habitat protection, and community engagement. Well-trained rangers with advanced technology apprehend poachers and dismantle trafficking networks. Translocation, population management, and reducing demand for rhino products are also crucial.

Organizations like the International Rhino Foundation and Save the Rhino International, alongside governments and communities in countries with rhino populations, are actively involved in rhino conservation.

Be part of the solution by simply spreading these rhinoceros facts.

Related: To further explore the animal kingdom, check out some of the other animals that start with R.