Gone too soon: Brookfield Zoo in mourning after bottlenose dolphin calf’s sudden death

Less than a week after announcing the birth of the zoo’s first bottlenose dolphin calf in more than a decade, Brookfield Zoo is in mourning. The four-day-old dolphin calf, which arrived on Saturday, June 7, passed away on Wednesday, June 11, the zoo announced on social media.  According to the Instagram post, the calf had displayed healthy signs of development before the sudden loss.

“The first few days after birth are a vulnerable, critical timeframe for dolphin calves,” said Dr. Rita Stacey, Brookfield Zoo Chicago senior vice president of programs and impact, in a press release. “This is a devastating loss for our Zoo community, especially the animal care and veterinary teams who dedicate their lives to the well-being of animals in our care. They provided exceptional, around-the-clock care to Allie and her calf. While the calf was progressing well, dolphin neonates face immense biological challenges. We are deeply saddened by his sudden passing.” 

According to the press release, the first year of a dolphin’s life is filled with overcoming challenges such as nursing underwater, navigating its new environment, and learning how to sleep while the mother pulls it along in a slipstream or wake. These milestones apply to both dolphins in the wild and under professional zoo care. Dr. Stacey noted that the calf had been reaching all of its milestones with the help of its mother, Allie. 

Despite having 24-hour, minute-to-minute observation by zoo staff members, the calf’s behavior changed rapidly Wednesday evening before becoming unresponsive. The press release goes on to explain how one in five calves that are born to first-time dolphin mothers pass away in the first year of life. 

"We know our guests and supporters share this sadness with us," said Dr. Stacey in the zoo’s announcement. "This calf’s birth brought hope and joy, and his sudden loss reminds us of the delicate balance of life."

Zoo staff are continuing to closely monitor Allie and the dolphin group at this time. The zoo went on to explain that while heartbreaking, every dolphin birth positively impacts and improves scientific understanding of dolphin care