One of the Gladys Porter Zoo’s Western lowland gorillas, Martha, gave birth to her fourth baby girl Tuesday afternoon.

It’s a moment that 16-year-old Jeff Brown will not forget.

“At first, I didn’t understand what was going on,” the Hanna High School junior said.

“I noticed that all the gorillas were excited and crowded together. It was just exciting. Then I saw this newborn and the umbilical cord. I probably won’t ever forget it,” said Brown, who was visiting the zoo with his family.

The 5 pound baby was born at approximately 4:30 p.m.

“It never stops surprising me. I’m always just amazed,” Facilities Director Jerry Stones, who raised Martha, her sisters, and many other gorillas, said of the newest addition to the zoo’s gorilla family.

Stones knows every gorilla in the zoo’s Gorilla Island as if they were his own.

“I am proud of this baby as if it were mine,” Stones said.

The babies born to Martha and Moja have all been girls. Moja has been at the zoo about 10 years and has fathered 12 babies.

“She was just so happy,” Stones said of 18-year-old Martha, whom he describes as a loving mother.

“The baby is feeding well,” was the report that Stones received Tuesday at 7:30 p.m. from the zoo’s night watchman, Manuel Garcia.

“She is nursing,” Garcia reported.

Martha and the yet-unnamed baby are not available for viewing yet. They are being monitored, but likely would be allowed in public viewing areas soon.

And as staff celebrates a new birth, they also celebrate the honor recently received from the Association of Zoos and Aquariums. The staff’s work — in conjunction with Mexican conservationists — to protect Kemp’s ridley sea turtle nesting sites along the Mexican coastline made the association’s list of the top 10 wildlife conservation success stories for 2007.

“We’re really pleased,” zoo Director Patrick M. Bruchfield said.

“We will continue our work,” Burchfield said, pointing out that more than one million sea turtle hatchlings were released back into the Gulf of Mexico this year. “That is a milestone,” Burchfield said.