Rhinoceroses are the second largest mammals on land, so it must take long for the calves to develop in the womb. But how long is a rhino pregnant?
Rhinos’ pregnancy lasts around 15 to 16 months in the wild. But in captivity, it can extend to 18 months. They give birth to a single calf after this period.
Rhino males and females may exhibit different courtship toward one another before mating. However, it is not easy for an adult to be accepted as a worthy mate to their contemporaries.
How Do Rhinos Mate
Female rhinos reach sexual maturity at the age of 3 years. But male rhinos aren’t ready for mating until they are at least 7 years old. The intercourse follows different courtship behaviors, with the female mounting by the male from the back.
The whole process may seem dangerous to us, but the animals are built to sustain the damage. Still, sometimes the wounds might be fatal for the couple and cause them harm.
Territory Marking by Bull Rhino
The whole copulation starts from the male rhinos marking their territories and the females ovulating in that territory.
Sexually matured bulls start marking their land by spraying uring and feces around. They let others know that they claim a specific land and any reproductive cows within it. It is sort of a pre courtship behavior among them.
Ovulation by Female Rhino
Female rhinoceroses ovulate once every month and are receptive to young coves for one or two days. But female rhino does this only when her mom is not around. Because with the mother’s presence, the daughter doesn’t ovulate and hence gets no males attracted toward them. It is a kind of intelligent behavior seen among them.
Fighting off the competition
The bulls would fight other competitors off. They do this only for the receptive cows in their territory. The male rhinos come to know this through the scent coming from their contemporaries.
Otherwise, rhinoceroses are not known for defending harems of cows. However, they are polygamous beings. They are seen to partner with different individuals at times. One partnering could last for a mating season, days, weeks, or months.
Courtship Rituals
Finally, the courtship behavior begins. Rhinos gather at a place and try to win one another over by doing different physical activities. These include spraying uring, cocking the tail at an angle, energetically scraping dung, etc. female rhinos are seen to make a whistling sound to attract alphas.
She would keep following the bull around and might leave a scent behind her as she went. This also lets other receptive cows know that this bull is with her. After that, the cow would chase around the bull.
Copulation
The Courtship results in the bull rhino mounting the female rhino from behind. As soon as the female rhino begins her estrus, she allows the bull to mate. The process can last for 20 minutes to an hour. They keep doing this repeatedly until the estrus ends.
However, things can get intense during this time. The pair could be seen wrestling and fighting and biting one another. This might be very dangerous and exhausting for the couple.
Sometimes the injuries can lead one partner to death. Occurrences like this have happened throughout history.
How Long Is a Rhino Pregnant?
Rhinoceroses are pregnant for about 15 to 16 months in the wild. But in captivity, the longest gestation was recorded for about 18 months. They give birth to a single calf.
The mother rhino takes the whole responsibility of bringing up the child. The calf stays with her like a shadow. Because the newborn baby is weak and has no horn, thus it can’t protect itself.
The mother provides milk and protection to the young. This companionship lasts until three years for the girls and about five years for the boys. The birth of a new calf can also result in the rejection of the older sibling by the mom.
After that, the older ones are on their own and have to look after themselves. The interbirth interval for rhinoceroses can be 2.5 to 4 years. The number of calves they can have in a lifetime is arguable.
But different rhino species are seen to have around 11 babies in total. That is, if they are healthy and are willing to mate regularly.
For the first week of birth, rhino calves live entirely on their mothers’ milk. After nearly 7 to 10 days, they start nibbling on soft grasses and vegetables. Non-wooden vegetation is their favorite during this time.
Can Rhinos Mate Interspecies?
Rhinoceros are a broad group of animals that include about five species. They are
- White Rhinoceros
- Black Rhinoceros
- Indian Rhinoceros
- Javan Rhinoceros
- Sumatran Rhinoceros
Can rhinos copulate interspecies? Simply put, can white rhinos mate with black rhinos?
Yes, they can. This surprising fact was proven in captivity.
This cross-breeding happened in a large enclosure during the ’80s. Despite the noticeable significant differences between the two species, they cross-bred.
The major differences include the white rhinos being bigger and stronger. Besides, the white ones are grazers and hence have flat lips. However, the black rhinos have pointy tips and like to grab on the branches and leaves of trees.
In the 1980s, two female white rhinoceroses, one young white rhinoceros bull, and one black rhinoceros bull were kept in captivity together. However, one of the female rhinoceros got pregnant.
But the interesting thing is the young white rhino bull was only four at that moment. In natural circumstances, white rhinoceroses bulls don’t copulate at the age of 4. So experts couldn’t hold it responsible for impregnating the cow.
They had to conclude that the calf developing inside the female’s womb is one of the rarest cross-bred calves in the world. It was a cross between the white and the black rhino. However, it was scientifically proven more recently in 2004.
In 2004 scientists compared the chromosomes of the two rhino species with the hybrid baby. To their surprise, they made a breaking discovery. They found that among the 18 characteristics found in the chromosomal level of the new calf, 6 were from the black rhino, and 8 were from the white rhino.
This mind-blowing discovery proved that rhinoceros could, of course, crossbreed.
Conclusion
Rhinoceros give birth to a single calf at a time. Before that, their gestation period is prolonged. How long is a rhino pregnant? Let’s say about 15 to 16 months in the wild. Scientists have found many interesting facts in their breeding process.
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