National Zoo steps in after Amur tiger pair prove to be 'just friends' and won't mate
JUANA SUMMERS, HOST:
Amur tigers, also known as Siberian tigers, are the largest cats in the world. They are also endangered. Fewer than 500 of them roam the mountains of eastern Russia, but at the Smithsonian's National Zoo in Washington, D.C., zookeepers are trying to help two Amur tigers reproduce using artificial insemination. From member station WAMU, Jacob Fenston has the story.
JAYNE HUTCHESON: All right, last big breath, and then I'll take machine. Alissa, you'll take her head and her tube, please.
JACOB FENSTON, BYLINE: In the cavernous bunker-like concrete hallways beneath the lion and tiger habitats, a muscular 300-pound cat appears to be sleeping. She has thick orange and black fur, and her paws are as big as salad plates. A couple dozen National Zoo staffers are gathered in close.
HUTCHESON: I'm Jayne Hutcheson. I'm a certified veterinary technician here at Smithsonian's National Zoo. And I am breathing for our tiger right now. She is under anesthesia, so we have our portable anesthesia machine here.
UNIDENTIFIED PERSON: Does someone have the...
FENSTON: Nikita is 11 years old and big cat curator Craig Saffoe says she's never had cubs before.
CRAIG SAFFOE: We've been trying to breed Nikita with no success, so once we don't have success with natural breeding, we look to our scientists to help us with artificial insemination - all a part of trying to keep this species going.
FENSTON: Getting big cats to breed in captivity is not easy. For one thing, the animals are naturally aggressive with each other. Mating can be violent.
SAFFOE: We often think that, well, you just put two tigers together. Well, try that with humans. It doesn't always work out so well. This male - they get along, but it's effectively a platonic relationship. They get together. They head rub, but they just won't pull the trigger. They just won't breed.
FENSTON: Across North America, zoos try to help endangered animals by selectively breeding them, keeping up genetically diverse populations. It's a sort of insurance policy in case disaster strikes the wild populations. Zoos even rank individual animals based on how genetically valuable they are. Nikita is No. 5 among Amur tigers.
HUTCHESON: I am ready with the head. One, two, three.
FENSTON: It takes 10 people to lift the cat...
HUTCHESON: All right, clear the way.
FENSTON: ...And carry her onto a cart.
HUTCHESON: I'm going to reconnect her and give her a couple of breaths.
FENSTON: It's like in a hospital - that same mix of frenetic activity and choreographed precision. Reproductive physiologist Pierre Comizzoli uses an endoscope - a tiny camera - inside the tiger.
PIERRE COMIZZOLI: Voila. So you see I am in the cervix now.
SAFFOE: So he's carefully looking to place the sperm at exactly the right spot. This is the exciting part.
COMIZZOLI: So it went straight into the uterus or probably into the - one of the uterine horn because the uterine body is very small in those cats.
SAFFOE: It looks good, so the actual insemination took place.
FENSTON: So far, artificial insemination has rarely been successful with these tigers.
COMIZZOLI: I would say that the Siberian tiger is the largest of the wild cats, and it's always, you know, very impressive and very different from a cheetah or a leopard.
HUTCHESON: You still want her on one, Alissa?
ALISSA: Yeah, give her a couple big breaths. It's fine.
SAFFOE: Now we need to return the animal as safely as possible back to her enclosure, and then we just keep our fingers crossed, and we hope for the best.
FENSTON: Keepers at the National Zoo say they should know by early May if Nikita is expecting tiger cubs. For NPR News, I'm Jacob Fenston.
(SOUNDBITE OF SURVIVOR SONG, "EYE OF THE TIGER") Transcript provided by NPR, Copyright NPR.