CHICAGO – Early Saturday morning, a bottlenose dolphin at a Chicago zoo successfully gave birth to a calf, aided by another dolphin mother and recorded by zoo staff.

The birth took place at Chicago’s Brookfield Zoo where a team of veterinarians watched over and encouraged the mother dolphin, 38-year-old Allie, as she gave birth to her calf.

In video footage shared by the zoo on Saturday, voices can be heard urging, “Push, push, push,” as Allie swam around the tank with the calf’s small tail fin visible beneath her.

Then the calf wriggles free and instinctively darts to the surface of the pool for its first breath. Also in the tank was an experienced mother dolphin named Tapeko, 43, who stayed close to Allie through her more than one hour of labor. In the video, she can be seen following the calf as it heads to the surface, and staying with it as it takes that first breath.

It is natural for dolphins to look out for each other during a birth, zoo staff said.

“That’s very common both in free-ranging settings but also in aquaria,” said Brookfield Zoo Chicago Senior Veterinarian Dr. Jennifer Langan in a video statement. “It provides the mom extra protection and a little bit of extra help to help get the calf to the surface to help it breath in those couple minutes where she’s still having really strong contractions.”

In a written statement, zoo officials said early signs indicate that the calf is in good health. They estimate it weighs around 35 pounds (16 kilograms) and stretches nearly four feet in length (115-120 centimeters). That is about the weight and length of an adult golden retriever dog.

The zoo’s Seven Seas exhibit will be closed as the calf bonds with its mother and acclimates with other dolphins in its group.

As part of that bonding, the calf has already learned to slipstream, or draft alongside its mother so that it doesn’t have to work as hard to move. Veterinarians will monitor progress in nursing, swimming and other milestones particularly closely over the next 30 days.

The calf will eventually take a paternity test to see which of the male dolphins at the zoo is its father.

Zoo officials say they will name the calf later this summer.