The stork is going to have to call out the reinforcements: Shedd is expecting not one but two marine mammal calves, a Pacific white-sided dolphin in spring and a beluga whale due sometime in the fall.
We’re excited about these pending additions to the Shedd animal family. Beluga mom Mauyak (MY-ak) and dolphin mom Piquet (pee-KEHT) are healthy, and so far their pregnancies are progressing normally. And from our regular prenatal monitoring of the moms and the fetuses, we are already adding to what is known about two species that are not often seen in aquariums and are challenging to study in the ocean.
In fact, Shedd is one of only four North American aquariums that exhibit Pacific white-sided dolphins. Because this dolphin population numbers fewer than 20 animals, and females greatly outnumber males—Shedd has an all-girl group—the aquariums have joined efforts in a cooperative breeding program. Animals are moved among the four sister institutions to make the most of breeding opportunities and to protect the genetic diversity of the aquarium population as a whole.
Last year Piquet spent a number of months at one of the partner institutions, Miami Seaquarium, where she bred with Lii (LEE-ee). (While she was away, Shedd hosted one of Lii’s offspring from Miami, 5-year-old Ohana.)
This is the first pregnancy for 24-year-old Piquet. Her name means “female of small stature” in Tlingit, the language of a large group of Pacific Northwest Indians. She is indeed the smallest of Shedd’s dolphins, weighing about 200 pounds. A Pacific white-sided dolphin pregnancy lasts almost 12 months, so our best estimate is that Piquet will give birth in May.
Beluga whales have a longer, less easily determined, gestation period—14 to 16 months. Based on Mauyak’s regular exams and on what we know about beluga fetal development, we expect the 31-year-old whale to give birth between September and November. Mauyak, who is easy to recognize by the gray streaks on her expanding sides, has had two successful births since she came to Shedd from Point Defiance Zoo and Aquarium in Tacoma, Wash., in 1997—Qannik in 2000 and Miki in 2007.
The population of belugas in North American aquariums and zoos has also benefited from a cooperative breeding effort, this one involving seven zoological facilities including Shedd. Our large male, Naluark (nah-LOO-ark), who sired this calf, is currently at Connecticut’s Mystic Aquarium on a breeding exchange. Shedd has had five successful whale births since 1999.
Shedd’s marine mammal and veterinary experts acknowledge that cetacean pregnancies, especially among first-time mothers, often have low success rates for a number of reasons, not the least being the challenges facing an air-breathing animal that is born underwater. But Dr. Caryn Poll, section chief of medicine at Shedd, says that both moms-to-be are in excellent health, and ultrasounds and blood tests indicate that both calves are also doing great.
You can see for yourself how the calves are developing. The ultrasound image of Mauyak’s calf shows its head on the left—you can see the jaw and characteristic beluga “smile,” a hint of an eye, a pectoral fin sticking up and the rib cage.
The ultrasound video of Piquet’s calf shows it positioned with its head on the right. That pumping is the calf’s heart. As the image focuses in and out, you can also glimpse a cross-section of one of its pectoral fins, above the heart on the right.
These ultrasound images are among the data Shedd is amassing with each cetacean pregnancy. This information is shared freely with our colleagues throughout the international scientific community, filling the gaps in basic knowledge about these two species.
What we know about terrestrial animals and their reproduction, gathered over centuries, could fill libraries. But it was only four decades ago that the first beluga calf was born in a North American aquarium; Pacific white-sided dolphins were first bred about 20 years ago. By pooling data and hands-on knowledge, aquariums and zoos are experiencing an accelerating learning curve on everything from milestones in neonatal development to the best formula if a calf isn’t nursing. We have also become more adept at recognizing when mom is doing an excellent job or when the calf needs some assistance.
All this contributes to the goal of healthy, self-sustaining populations of the charismatic whales and dolphins that delight and enlighten aquarium guests, and thriving populations of these species in the wild, too.
You’ll continue to see Mauyak and Piquet taking part in daily programs in the Abbott Oceanarium. It’s the best thing for them. Consistent training sessions give the moms-to-be the physical and mental stimulation they always need and also provide our animal care staff members with regular opportunities to track the pregnancies. We’ll help you follow the calves’ development with ultrasound updates. And we hope you’ll visit Shedd often, because our marine mammals like to see you as much as you like to see them.
Posted by Karen Furnweger, web editor