With the survival of a species on the line, Cincinnati Zoo scientistsare hoping to mate their lone female Sumatran rhino with her littlebrother.
The desperation breeding effort with the rhino siblingsfollows a recent crisis summit in Singapore where conservationistsconcluded as few as 100 of the two-horned, hairy rhinos might remain intheir native southeast Asia. The species numbers have fallen by up to 90percent since the mid-1980s as development takes away habitat space andpoachers hunt them for their prized horns.
Rhinos overall aredwindling globally, and the Sumatran species descended from Ice Agewoolly rhinos is one of the most critically endangered.
TheCincinnati Zoo has been a pioneer in captive breeding of the rhinospecies, producing the first three born in captivity in modern times.Its conservationists this month brought back the youngest, 6-year-oldHarapan, from the Los Angeles Zoo and soon will try to have him matewith the zoo's female - his biological sister - 8-year-old Suci.
"Weabsolutely need more calves for the population as a whole; we have toproduce as many as we can as quickly as we can," said Terri Roth, whoheads the zoo's Center for Research of Endangered Wildlife. "Thepopulation is in sharp decline and there's a lot of urgency aroundgetting her pregnant."
Critics of captive breeding programs saythey often do more harm than good and can create animals less likely tosurvive in the wild. Inbreeding increases the possibility of bad geneticcombinations for offspring.
"We don't like to do it, and longterm, we really don't like to do it," Roth said, adding that thesiblings' parents were genetically diverse, which is a positive for theplan. "When your species is almost gone, you just need animals and thatmatters more than genes right now - these are two of the youngest,healthiest animals in the population."
The parents of the threerhinos born in Cincinnati have died, but their eldest offspring,11-year-old Andalas, was moved to a sanctuary in Indonesia where he lastyear became a father after mating with a wild-born rhino there.
Thefirst coordinated effort at captive breeding began in the 1980s, andabout half the initial 40 breeding rhinos died without a successfulpregnancy. Roth, who began working on the rhino project in 1996, said ittook years just to understand their eating habits and needs and decadesmore to understand their mating patterns. The animals tend not to beinterested in companionship, let alone romance.
"They'redefinitely difficult to breed because they're so solitary," Roth said."You can't just house them together. So the only time you can get asuccessful breeding is if you just put them together when the female isgoing to be receptive."
Mating between such close rhino relativesmight happen in the wild, Roth said, but it's difficult to know becausethe animals are so rare. If the offspring of such a mating then bredwith an unrelated rhino, the genetic diversity would resume in the nextgeneration, she said.
Harapan, who weighs about 1,650 pounds, willbe kept separate from his sister, who is a little smaller. On a recentmorning at the zoo here, he slathered himself in a mud hole, then ambledover to settle down in a pool of water.
When the time is right toreintroduce the rhinos, the zoo team won't dim the lights or play moodmusic. Instead, they will use a system of gates to bring the pairtogether. If they begin to fight or show other behavior indicatingthings aren't going well, the team will try to separate them, usingbananas for distraction.
Before then, Roth and the otherscientists will have measured Harapan's testosterone levels while usingultrasound and other monitoring to know when Suci is ovulating.
"You should use the science to guide you," Roth said. "We have really relied on the science."
Ifthe breeding is successful, the zoo will be celebrating a fourthSumatran rhino birth about 16 months later. If not, other efforts willcontinue.
Indonesian conservationists have been trying to mateAndalas, the oldest brother, with two other females there after lastyear's success. His semen has also been banked, but there have been noreported successful artificial inseminations yet.
At the Singaporesummit, Indonesian and Malaysian authorities pledged to work togethermore closely on species survival efforts. Conservationists say specialrhino protection patrols have thwarted poachers who kill rhinos to takehorns that can be worth tens of thousands of dollars on the blackmarket. The horns are sought for medicinal and other uses - by legend,rhino horns are said to have aphrodisiac powers.
While theSumatran rhino isn't a particularly popular or even recognizable animalto the public at large, Roth said, the species contributes to the globalneed for healthy forests with its role in the ecosystem clearing smallsaplings and brush, and helping spread seeds and make trails smalleranimals use. Also, the rhinos don't threaten humans nor damage theircrops.
"There's no human-rhino conflict," Roth said. "Are we goingto put enough value in wildlife to share the earth with this ancient,peaceful, noninvasive species? If we let the Sumatran rhino die, whatare we going to save?"