Two beluga whales at the Shedd Aquarium have proved that, despite scientific evidence to the contrary, in beluga society it doesn’t necessarily take three or more participants to get in the family way.
In recent years marine biologists discovered female belugas are much more likely to become pregnant if, during the March to May breeding season, more than one male is around to mate with.
So aquarium officials were surprised and pleased when they found that Naya, an 11-year-old female beluga, is pregnant with her first baby. The father, 16-year-old Naluark, has been the only male beluga at the Shedd for more than a year after the aquarium’s other male, Inuk, was lent out in 1999.
The baby is expected to be born next July, officials announced Tuesday.
The Shedd had no beluga pregnancies until 1997, when it brought Inuk from Point Defiance Zoo in Tacoma, Wash., to join Naluark. In the next three years, four babies were born. Two of those survived and are thriving.
“We are cautiously optimistic about Naya’s calf,” said Ken Ramirez, the Shedd’s director of marine mammal husbandry. “Beluga babies born to first-time mothers more often than not do not survive. But we have a staff that has experienced a number of births now, so we are more alert for what to look for if there is trouble.
“More importantly, Naya has witnessed these births, and we know that belugas seem to learn from observation, and perhaps that will increase the chances of a good birth, too.”
About 40 belugas are now living in aquariums in the United States and Canada, Ramirez said. The aquariums participate in a beluga breeding cooperative.
As part of that exchange program, the Shedd lent Inuk to Mystic Aquarium in Connecticut in 1999, leaving Naluark as the sole male at the Shedd. He had been sexually active with the Shedd’s females last year, but no pregnancies resulted, said Ramirez.
At 11, Naya is about the normal age for a first beluga pregnancy, Ramirez said. Successful births in the wild are most often seen in females at ages 16, 17 or 18.
Through monitoring of hormonal levels, the Shedd staff had suspected since July that Naya was pregnant, Ramirez said. Her pregnancy was recently confirmed by ultrasound exams.
Most visitors won’t be able to discern Naya’s pregnancy, he said, because the large amount of blubber whales carry masks the bulge of the fetus.
As Naya’s pregnancy progresses, she’ll be given her own pool and will stop taking part in public presentations.
