Another secret is that the cold, conductive gel, a mild shock to so many pregnant women, is not necessary. The probe is applied to the dolphin's midsection mostly underwater.
Want a third secret? The patient gets sushi afterward, or at least the variation on sushi that is a staple of dolphin training at Brookfield Zoo.
To mix an animal metaphor, the suburban zoological park let the cat out of the bag Monday, revealing that three of its dolphins are pregnant.
The births, expected in June/July, September and November, will be the first among Brookfield's Atlantic bottlenose dolphins since 2005. The dolphin facility rehabilitation, ending in 2010, had forced a reproduction program hiatus at Brookfield, which says it is the country's first inland facility to feature marine mammals, beginning in 1960.
Monday saw one of the weekly checkups for two of the pregnant dolphins, 26-year-old Allie and 31-year-old Tapeko. The procedures went swimmingly.
In a smaller holding pool behind the main one used for shows, the dolphins took turns sidling up to pool's edge. A trainer kept a hand on the animal for comfort.
And as the animals stayed there for up to five minutes, veterinarian Jennifer Langan and marine mammal curator Rita Stacey lay down on a foam pad poolside and used the imaging technology to report on the fetuses' health.
“The baby already has blubber, just like mom does,” Langan said of Allie's forthcoming offspring, who, if all goes well, will be 12 months in gestation and come out — tail first — weighing about 40 pounds.
“That thing in the middle there,” she said, pointing at the screen, “that's the fetal heart. Very nice and consistent. Normal development.”
The calves will spend their early years at Brookfield, then, depending on their sex, be moved to another facility (males) or stay to live and, it is hoped, breed, alongside their mothers.
That touches on perhaps the biggest secret of all. Like many nurses and doctors who perform ultrasounds on humans, Langan is pretty confident she knows the sex of the babies, but she isn't telling. “We want it to be a surprise,” she said.
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