A bottlenose dolphin safely delivered a calf early Saturday morning at Brookfield Zoo Chicago, a “momentous occasion” that marks the first dolphin birth in more than a decade at the west suburban zoo.
Allie, a 38-year-old bottlenose dolphin and experienced mother of four, gave birth to the calf — which will be named later this summer — at 12:22 a.m., the zoo said in a news release. Veterinarians estimated that the calf weighs between 33 to 37 pounds and is 115 to 120 centimeters long.
“Every birth is a remarkable learning opportunity, and the scientific information we gain benefits marine conservation efforts,” said Dr. Mike Adkesson, the zoo’s president and CEO. “The birth offers a moment to celebrate the incredible work and dedication of our team to ensure the health and well-being of the animals in our care.”
Allie began showing signs of labor Friday morning when her body temperature dropped about a degree, the zoo said. By 11 p.m., the calf’s flukes presented itself, and within less than an hour and a half the calf was born, the zoo’s first since 2014. A video showed the calf swimming up to the water’s surface for its first breath alongside Allie and Tapeko, another dolphin and an experienced mother.
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“The calf came out very strong,” Dr. Jennifer Langan, senior veterinarian, said in the video one hour after the delivery. “It has been breathing well, and it’s developing new skills that dolphins have to develop really quickly. That includes learning how to surface to breathe, learning how to move its flukes.”
The calf reached other developmental milestones as well, including “slipstreaming,” which is when a calf gets pulled along by its mother so that it doesn’t have to work as hard to swim, the zoo said. The calf’s dorsal fin and tail flukes are also pliable and lack firmness, but will gradually stiffen in a few days.
These milestones, which staff are monitoring “around the clock,” are important because although calves are born fully developed after a 12-month gestation, they heavily rely on their mother for nutrition, navigation and to conserve energy. A calf’s first year of life can be particularly precarious. In the wild, 1 in 5 calves born to first-time mothers don’t survive their first year, the zoo said.
“The first 30 days are a critical time frame for Allie and her calf,” said Dr. Sathya Chinnadurai, the zoo’s senior vice president of animal health, welfare and science. “We’re closely monitoring behaviors and milestones to gauge the calf’s progress, like its first breath of air, bonding with its mother, growth and an increase in nursing efficiency.”
Staff will confirm which dolphin is the calf’s father in the coming months, the zoo said.
Brookfield Zoo has a long history of dolphin care and research. In 1961, it opened the country’s first inland dolphin aquarium. For over five decades, the zoo has also led the Sarasota Dolphin Research Program in Florida, the world’s longest-running wild dolphin conservation program, which studies bottlenose dolphins as indicators of the overall health of the marine ecosystem, as well as the presence of diseases and toxins like contaminants, runoff, red tides and algal blooms.
The zoo’s Seven Seas dolphin habitat is temporarily closed while the calf acclimates to the dolphin group.