FRESNO, Calif. (AP) — An elephant calf has been born at a California zoo that has embarked on an elephant breeding program.

The Fresno Chaffee Zoo said African elephant Nolwazi gave birth early Friday and will receive round-the-clock surveillance from staff at the zoo, which has not previously had one of its elephants give birth.

“This is a historic moment for the Zoo,” chief executive Jon Forrest Dohlin said in a statement.

The zoo about 150 miles (240 kilometers) southeast of San Francisco in central California has embarked on a program to breed elephants in the hope they can be seen by zoogoers in years to come. The move, however, has faced criticism from some animal activists who don't want to see elephants in zoos due to their complex needs, and as some larger zoos have phased out their elephant programs, opting instead to send the animals to sanctuaries with more space.

The zoo in Fresno brought in a male elephant in 2022 hoping he'd breed with Nolwazi and her daughter, Amahle. Amahle is also due to give birth in coming weeks, the statement said.

The future of elephants — which have relatively few offspring and a 22-month gestation period — in zoos hinges largely on breeding.