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Critically endangered Sumatran rhino is pregnant

Conservationists are celebrating a pregnancy in one of the world’s most endangered species, the Sumatran rhino, the International Rhino Foundation (IRF) said yesterday. Photo of Ratu courtesy of Sumatran Rhino Sanctuary “The pregnancy of female Ratu, born in Indonesia, and male Andalas, the first of only three Sumatran rhinos born in captivity in more than...

Conservationists are celebrating a pregnancy in one of the world’s most endangered species, the Sumatran rhino, the International Rhino Foundation (IRF) said yesterday.


Photo of Ratu courtesy of Sumatran Rhino Sanctuary

“The pregnancy of female Ratu, born in Indonesia, and male Andalas, the first of only three Sumatran rhinos born in captivity in more than 112 years, is giving hope to international rhino biologists,” the Florida-based nonprofit said in a statement.

The breeding was achieved at Indonesia’s Sumatran Rhino Sanctuary in Way Kambas National Park after international efforts led to the pair’s introduction. The calf is expected to be born in May 2011.

“This is no ordinary pregnancy,” IRF said. “Andalas and Ratu were brought together through international goodwill and cooperation in an effort to save this critically endangered species.”

Ratu wandered into a village just outside Sumatra’s Way Kambas National Park in 2006; Andalas was born at the Cincinnati Zoo & Botanical Garden in 2001, grew up at the Los Angeles Zoo and was transferred from the L.A. Zoo to the Sumatran Rhino Sanctuary in 2007. The 10,000-mile journey by plane, truck, and ferry took 63 hours.


Photo of Andalus courtesy of Sumatran Rhino Sanctuary

Three years after Andalas’ relocation to Indonesia, he and Ratu mated. The breeding followed months of gradual introduction by scent, sound, sight, and finally, physical proximity, ultimately resulting in the pregnancy, IRF said.

“A combination of sound science, international collaboration among government, nonprofits, and zoos, as well as timing and personal chemistry, has led to this groundbreaking event,” said Susie Ellis, executive director of the International Rhino Foundation.


Photo of Andalus and Ratu courtesy of Sumatran Rhino Sanctuary

“Sumatran rhino numbers have decreased by more than 50 percent over the last 15 years in the wild. Every individual counts, and the captive population represents not only an insurance policy for the wild population, but also a means to study the basic biology of the species, which we must understand in order to save them,” Ellis said.

“Ratu’s pregnancy represents the hope for a future generation.”

The Sumatran rhino is the rarest of the five rhino species. Its population is about 200 individuals in the wild and 10 in captivity worldwide, according to IRF estimates. “Ratu’s pregnancy represents the hope for a future generation,” IRF said. 

sumatran rhino facts.jpg

“We have been waiting a long time to share news of a rhino pregnancy,” said Dedi Candra, the Sumatran Rhino Sanctuary’s animal collection coordinator. “With help from our partners, we have worked tirelessly to keep these animals healthy and breeding. Our dedicated keepers deserve a great deal of the credit.”

“The Los Angeles Zoo is anxiously awaiting the birth of Ratu’s calf in Indonesia,” said John Lewis, Los Angeles zoo director. “We are longtime supporters of this program. Although we miss Andalas at the zoo, we are so proud to have helped contribute towards the conservation of rhinos by sending him back to Indonesia.”

In 1984 a group of reproductive biologists, zoologists and conservationists formed the Sumatran Rhino Trust, an agreement bridging several countries and symbolizing hope for the conservation of an entire species. The Sumatran Rhino Sanctuary is a 250-acre complex built and funded by IRF.

The sanctuary is operated in partnership with the Indonesian Rhino Foundation under an agreement with the Indonesian Ministry of Forestry. It is home to five rhinos that are part of an intensively managed research and breeding program aimed at contributing to the conservation of the species in the wild. The rhinos reside in large, open areas where they can experience a natural rain forest habitat while receiving state-of-the-art veterinary care and nutrition, according to IRF.

Terri Roth, director of Cincinnati Zoo’s Center for Conservation and Research of Endangered Wildlife (CREW) and vice president for IRF’s Asia programs, has used her extensive training in reproductive biology to produce three Sumatran rhinos beginning with Andalas in 2001, utilizing hormonal assays and ultrasound techniques to determine the optimal time for introducing males and females, IRF said.

“Sumatran rhinos are very solitary by nature and very aggressive towards one another except when a female is in estrus,” Roth said. “Through science we can determine when the female is ready to ovulate so that she is paired with a male at the right time and fighting is minimized while the likelihood of conception is optimized. It is wonderful to see the science developed at CREW help our Indonesian colleagues achieve success in the forest of Sumatra.”

Back up to wild rhino population

Captive Sumatran rhinos fill many roles, Roth said. “They represent a valuable resource for learning about the species’ basic biology which can facilitate efforts to monitor and protected them in the wild. They serve as ambassadors for their species helping to educate both children and adults about rhinos and the rainforest, and they are becoming increasingly important as a back up to the wild population as the latter continues to decline.”

“The Sumatran Rhino Sanctuary has been encouraged by Cincinnati Zoo’s success,” said Widodo Ramono, executive director of the Rhino Foundation of Indonesia. “Our staff has adapted the Cincinnati Zoo’s methodology to the local environment at the Sumatran Rhino Sanctuary, particularly ultrasonographic techniques, to achieve this result.”

“Captive breeding … a critical part of an integrated strategy for the Sumatran rhino’s recovery.”

“While captive breeding is not a substitute for protecting the species in the wild, it is a critical part of an integrated strategy for the Sumatran rhino’s recovery,” Ellis said. “The International Rhino Foundation, through its local partner, the Indonesian Rhino Foundation, also operates anti-poaching units in three Indonesian national parks. Thanks to those programs, there has been no rhino poaching in the last five years, and poaching of other large vertebrates which share rhino habitat has decreased significantly.”

Development of a viable and holistic program that involves captive breeding will provide insurance against the difficulties and uncertainties of protecting the Sumatran rhino in the wild, IRF said in its statement. “Solid success with this species may provide a model for development of a similar program for the critically endangered Javan rhino, whose population is more stable but numbers no more than 50 individuals in the wild, with no insurance population in captivity.

“Indonesia harbors two critically endangered rhino species, but with far less attention than African rhinos, under pressure from a 15-year high in poaching for horn, which is used in traditional Asian medicine as an analgesic.”

The International Rhino Foundation is a global not-for-profit organization dedicated to the survival of the world’s rhino species through conservation and research, and increasing awareness about the plight of the rhino. Learn more about the IRF and how you can support rhinos on the International Rhino Foundation Web site.

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