Philadelphia Zoo plays matchmaker: Kira, this is Motuba

As Motuba bounded and barreled up a flight of five stairs, smacking his humongous hands on the glass window in front of him, 4-year-old Mai Phan let out a gasp.

"This is a first for her," said Mai's mother, Melanie, who had taken her daughter to the Philadelphia Zoo for the day.

Standing in front of them was a majestic mammal more than 10 times Mai's weight. Mai, pressing her hands on the glass, looked on as Motuba strutted, on all fours, to the center of the room.

All 432 pounds of him.

The Philadelphia Zoo welcomed Motuba, a 29-year-old western lowland gorilla, on Tuesday. He comes to the zoo on a breeding recommendation from the Gorilla Species Survival Plan, dedicated to maintaining a healthy and genetically diverse population of western lowland gorillas in zoos across the nation.

He'll be encouraged to mate with Kira, a female about half his age. More than encouraged, as zoo staffers will do everything they can to facilitate you know what.

Kristen Farley-Rambo, the zoo's gorilla-keeper, said Motuba was brought over because he and Kira were determined to be a good genetic match. The courtship, albeit supervised, will start in about a week, after an initial acclimation period for Motuba.

Motuba joins four other lowland gorillas who call the zoo their home: Kira and another female, Honi, and two young males, Louis and Kuchimba.

Farley-Rambo said the zoo had been looking for a mature male like Motuba for years. Western lowland gorillas are considered critically endangered. Originally from central Africa, they are the subspecies of gorilla most often found in zoos.

"This has been a long time coming, so we're obviously very excited," she said of Motuba's arrival.

His trip to Philadelphia began Thursday, when he was loaded into a crate at the Henry Doorly Zoo in Omaha, Neb. One FedEx plane ride later - he only slightly exceeded the commercial airline weight limit - he arrived at Philadelphia International Airport.

As a flurry of camera shutters captured Motuba's first public moments in Philadelphia, the imposing silverback grinned sheepishly, posing and flexing his muscles for dozens of zoo volunteers and schoolchildren.

The entire introduction, which lasted about a half-hour, looked more like a bodybuilding competition than a zoo display. Motuba spent much of his public debut surveying his new surroundings, ignoring the carrot-and-broccoli-topped "Welcome to Philadelphia" cake that the zoo staff had made for him.

"It's all very surreal," Farley-Rambo said. "These guys are like family to us, so it's a very special moment."