SAN DIEGO (KGTV) --The San Diego Zoo announced that Mabel, a four-year-old pygmy hippopotamus, gave birth to her first calf -- the first successful pygmy hippo birth at the zoo in over 30 years.

Mabel gave birth to the 12-pound male calf on April 9, zoo officials said.

The still-unnamed calf and Mabel are doing very well, according to zoo officials, with the baby “getting lots of attention from the first-time mother.”

The calf is meeting and surpassing the milestones that wildlife care specialists watch for in a young pygmy hippo, including the ability to go underwater. To prepare the calf for exploring in the water, wildlife care specialists placed a small, shallow tub in the indoor habitat. When mom and her calf were given access to the outdoor maternity habitat, staff added a fence to prevent the calf from venturing into too-deep water. The calf demonstrated the natural adaptations and instincts of pygmy hippos -- to close their nostrils and to hold their breath under water -- and on Friday, both Mabel and the calf have full access to the pool in the maternity yard.

It will be approximately a month before Mabel and her calf, who now weighs 25 pounds, will have access to the main habitat. When this happens, wildlife care specialists will rotate mom and calf with the 13-year-old male pygmy hippo, Elgon. The calf will not be introduced to his father because pygmy hippos do not live in family groups, and males do not play a role in the rearing of offspring.

According to zoo, pygmy hippos are considered endangered species by the International Union for Conservation of Nature. The hippos are located in the forests of West Africa.

Currently, there are fewer than 2,500 pygmy hippos in four African countries -- Côte d'Ivoire, Guinea, Liberia and Sierra Leone.