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Two Como Park Zoo gorillas are expecting babies.

The babies would be the first and second in the St. Paul zoo’s 55-year history of having a gorilla exhibit.

The infants would expand the zoo’s Gorilla Forest from seven to nine gorillas. Primate specialists anticipate 12-year-old Alice will give birth sometime between Oct. 18 and Dec. 12, and 11-year-old Dara will give birth between Dec. 18 and Feb 1.

The father of both offspring is 28-year-old Schroeder, considered by conservationists to be genetically valuable. Western lowland gorillas are endangered because of habitat loss, poaching and disease, according to zoo staff.

The two females are recent arrivals to the 16-month-old exhibit, coming as part of the Association of Zoos and Aquariums Gorilla Species Survival Plan.

Infants typically weigh from 4 to 5 pounds when they’re born. Immediate bonding is considered crucial, because the mortality rate for baby gorillas is about 40 percent, zoo staff said. An older female, Nne, 26, is expected to help show the mothers how to care for the baby gorillas.

Once they’re born after eight months of pregnancy, the babies are not expected to appear in public for perhaps six weeks. By summertime, the infants are expected to graduate from being carried on their mothers’ chests and move to riding on their mothers’ backs and playing on the ground by their mothers. As the young gorillas get older, they’ll play with other family members, including their father.

Debra O’Connor can be reached at 651-228-5453.

Follow her at twitter.com/DebOConnorPP.