Western lowland gorilla born at Lincoln Park Zoo Bana, a 16-year-old western lowland gorilla, holds its newborn baby in their habitat at the Lincoln Park Zoo on November 22, 2011 in Chicago. The unnamed baby was born November 16 to Bana, who was brought in from Brookfield Zoo to mate with the 22-year old silverback Kwan. Bana gave birth again on Oct. 11, 2012. CHICAGO, Oct. 17 (UPI) -- Chicago's Lincoln Park Zoo said a 6-day old western lowland gorilla is the 51st gorilla to be born at the facility. The zoo's Regenstein Center for African Apes said the baby was revealed to the public Wednesday after it was born Oct. 11 to mother Bana, 17, and father silverback Kwan, 23, the Chicago Sun-Times reported Wednesday. The baby, which has not been named or had its sex determined by the zoo yet, is the 51st baby gorilla born in the zoo and brings the facility's western lowland gorilla population to 11. The western lowland gorilla is considered a critically endangered species, the zoo said.