Memphis Zoo celebrates birth of 2 Sumatran tiger cubs

May 22 (UPI) -- The Memphis Zoo welcomed two endangered Sumatran tiger cubs earlier this month, the first born at the zoo in more than two decades.

The zoo said Dari, a 7-year-old Sumatran tiger, gave birth to the cubs on May 5 with the father, a 4-year-old tiger named Gusti.

"After practicing for several weeks to perfect the technique, we were elated to definitively confirm a viable fetus on the left side," Memphis Zoo's Senior Veterinarian Felicia Knightly said. "Shortly after, we confirmed a second fetus on the right side."

Sumatran tigers were last born at the zoo in 1998 and the mother of those cubs is Dari's grandmother.

The number of tiger species on the planet has declined from nine to six and the zoo said Sumatran tigers are "one of the rare species" that are managed globally in zoos and related facilities.

"As the last of the island tigers, preserving Sumatran tigers is critically important," Dan Dembiec, West Zone curator, said. "Sumatran tigers are managed collaboratively in breeding programs by accredited zoos globally. So, the birth of tiger cubs here at the Memphis Zoo is a milestone with a worldwide impact."

Knightly said mating tigers in captivity is always a two-step process, first getting them comfortable in their new surroundings before introducing them to each other in hopes that love with prevail.

"We had to introduce them to each other, which can have an inherent risk, as you never know how tigers will react to each other, and we were lucky Gusti and Dari hit it off. With two first-time mates, it took almost a year for them to understand what to do, but clearly, they figured it out." Knightly said.

Zookeepers will closely watch over the cubs before they receive vaccinations at six weeks old and are shown their outdoor habitat and three months old.

"We will document milestones in their development, such as when their eyes open when they are strong enough to leave the nest box and when they start sampling diet," Knightly said.