The Denver Zoo celebrated World Rhino Day Sunday with a fitting announcement: Tensing, an 11-year-old greater one-horned rhino, is with child.
Rhinos have one of the longest gestation periods of all mammals, at an average of 470-480 days. Thus, the calf is expected to be born in the spring of 2020.
Animal pregnancies always are a cause for celebration at zoos, according to officials.
“Tensing’s pregnancy is an incredible example of what Denver Zoo — and other zoos accredited by the Association of Zoos and Aquariums — do to ensure the survival of many vulnerable, threatened and endangered species,” said Brian Aucone, senior vice president for animal sciences in a news release.
The pregnancy was the result of several years of trying to artificially inseminate Tensing, including working with partner zoos such as The Cincinnati Zoo and Omaha’s Henry Doorly Zoo and Aquarium, he said. The 12th attempt to artificially impregnate the rhino worked.
Weekly voluntary ultrasounds have shown the fetus is healthy and the size of a large watermelon, officials said. Baby rhinos can grow to weigh 6,000 pounds as adults.
Rhinos are born without the horn they’re famous for and grow them as they age.
Once widespread, the population of greater one-horned rhinos — also known as Indian rhinos — plunged in the 20th century as they were hunted for sport and viewed as agricultural pests.
Protection efforts have helped greater one-horned rhinos recover to an estimated 3,500 animals, with managed breeding programs at zoos designed to help safeguard the species’ survival.