The stork will soon visit the Blank Park Zoo.

Ayana and Kiano, the south side park’s rare eastern black rhinos, are expecting a baby in late October or early November, according to the zoo. Ayana, the female, is carrying the little one and Kiano is her male partner.

Ayana's pregnancy is the first confirmed fertilization among the eastern black rhino zoo population in almost two years, marking a major turning point in the species' decadeslong decline, experts said.

Listed as critically endangered by the World Wildlife Fund, Des Moines' rhinos are two of just 46 eastern black rhinos currently housed in North American zoos, according to the Association of Zoos & Aquariums, a leading zoological nonprofit organization. Only six of those 46 rhinos are breeding females.

“This is fantastic for us and for the rhino population,” said Robyn Scanlon, a large animal zookeeper who has been working with Ayana and Kiano for three years.

In the wild, rhinos "are poached very, very frequently," she said. "Their numbers have declined quite drastically over the past century…so having our own baby and being able to contribute to that population is awesome."

The birth announcement was also met with joy across the rhino conservation world. Ayana's pregnancy is a hopeful sign for the species, a population which zoos have been working diligently to save and grow, said Dr. Terri Roth, a rhino expert at the Cincinnati Zoo who worked with Blank Park to certify this fertilization.

"Each confirmed pregnancy of a black rhino is a big deal because of the urgency around breeding," she said. "The managed (or zoo-based) population has taken a turn for the worst in recent decades, so we are pleading right now with zoos that have animals that are recommended for breeding to get their animals together and confirm a pregnancy."

The Association of Zoos and Aquariums, which "focuses expertise and resources on saving some of the most vulnerable species from extinction," was elated to hear about Ayana's gravidness, said spokesman Rob Vernon.

"Anytime we learn of a pregnancy, especially with an endangered species like the black rhino, it is very good news," Vernon said. "We will keep a close eye on this one!"

Ayana and Kiano moved into Blank Park's $4 million African exhibition in 2012. Both were born in captivity — Ayana at a Miami zoo and Kiano at the Great Plains Zoo in Sioux Falls, S.D. — and began breeding in July, soon after they reached sexual maturity, Scanlon said.

Since then, the pair's keepers have suspected Ayana may be pregnant. But rhino pregnancy is difficult to confirm due to the animal's size, skin thickness and a “dark period” in the first six to nine months where the baby isn’t easily detectable, Scanlon said.

In January, the zoo purchased a special probe to see if in-house vets could confirm the baby. When they failed to conclusively determine whether Ayana was pregnant, the zoo asked veterinarians from Iowa State University to take a look. But since they were comparing a rhino pregnancy to a horse or cattle pregnancy they, too, couldn’t be sure, Scanlon said.

The zoo then called Dr. Roth, who was able to substantiate the pregnancy and, on April 22, showed the keepers the calf via ultrasound for the first time.

“Roth taught us and our vets what to look for, so we could keep our eye on the fetus,” Scanlon said. “This is especially exciting for (the keepers) because we’ve all been a part of this from the beginning.”

The zoo is “cautiously optimistic” that Ayana will carry to term, said Blank Park spokesperson Ryan Bickel. “You can’t be sure what exactly will happen when it comes to these things, but she is far enough along that we feel we are in a good place."

Dr. Roth agreed: "Pregnancy loss in rhinos is pretty common…but black rhinos usually carry well, so I think there is great reason to be optimistic."

Even though Ayana is scheduled to give birth in late October or early November, the keepers are not sure when the baby will be on display.

“Because the species is so endangered, we want to make sure it is healthy and everything is OK before we put it on exhibit,” Scanlon said.

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