Riverbanks Zoo says a 12-year-old gorilla named Kazi has been pregnant for about four or five months. Her baby is due likely sometime in June.
Veterinarians say the gorilla is in good health and there are no complications so far, but first-time gorilla mothers are more likely to suffer complications.
The zoo in Columbia expected to welcome its first gorilla baby last spring, but the animal died while being delivered.
The zoo said in a statement that the mother and father are western lowland gorillas which are considered critically endangered species with just 100,000 left in the wild.
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