Brookfield, Ill.—Chicago Zoological Society animal care specialists continue to be cautiously optimistic with the progress of two male dolphin calves born at Brookfield Zoo: a 6-week-old dolphin calf that marine mammal staff has been handrearing around the clock since his birth and an 8-week-old calf, the fifth to be raised by Tapeko, his 31-year-old mother.

“We are pleased with the progress the handreared calf has made during his first six weeks of life,” said Jennifer Langan, DVM, Dipl. ACZM, associate veterinarian for the Society. “However, he still remains in guarded condition as he has several milestones he needs to achieve over the next few months before we would consider his situation less critical, including eating solid fish on his own, being introduced to the other members of the dolphin group, and finally becoming independent.”

The calf being handreared was born to Spree, 11, on October 28. Spree, an inexperienced mother, was not providing adequate maternal care. At that time, Chicago Zoological Society’s Animal Programs staff made the decision to intervene to provide necessary neonatal care.

 “The health and welfare of the animals in our care is our highest priority here at Brookfield Zoo,” said Bill Zeigler, senior vice president of animal collection and care for the Society. “Caring for this calf has been a zoo-wide effort involving the collaboration of several departments to provide him with around-the-clock observation, care, and support.”

The calf has been gaining weight and appears to be thriving due to the tremendous dedication of a team of staff from the Marine Mammal, Veterinary Services, Life Support, and Animal Nutrition Departments. Within the marine mammal community, there have been only a few documented cases of a newborn dolphin calf being handreared.

Since his birth, the unnamed calf has spent the majority of his time in a “nursery” pool set up specifically for a newborn dolphin’s needs. “A member of the marine mammal staff has been in the pool with the calf 24 hour a day providing him with the necessary support, including feeding him, conducting important behavioral observations, taking breath rates, and documenting his growth and weight measurements. All of this data assists us in making decisions regarding his constant care,” said Rita Stacey, marine mammal curator, who added “everyone in the zoo family is pulling for this little guy.”

Although the calf is receiving a dolphin milk formula, during his first week of life he received his mother’s milk, which contains vital nutrients and antibodies for his health and immunity. Because of the relationship between the dolphins and their trainers, Spree voluntarily allowed staff to collect milk from her.

Additionally, the 8-week-old calf born on October 16 to Tapeko continues to do very well. Marine mammal staff monitored him around the clock for the first 30 days of his life, which is the most critical period. During this time, staff used EthoTrak, an electronic behavior-monitoring program that was developed by a team of Chicago Zoological Society computer programmers and biologists and is now used by other zoos around the country. Marine mammal staff recorded nursing bouts, slipstreaming behavior, and other developmental behaviors. Observations will continue on the calf’s development as well as the social dynamics of the dolphin group.

The Seven Seas Underwater Viewing Gallery has reopened so that guests will be able to view Tapeko’s calf when he has access to the main pool. In addition to Spree and Tapeko and her calf, other members of the dolphin group that can be seen include Chinook, 30, the sire of both calves; Allie, 26; Noelani, 10; and Allison, 8. The dolphin calf being handreared will remain off exhibit so that staff can provide him with the best possible care. For updates and further information, visit