ATLANTA -- Georgia Aquarium officials hope a necropsy will determine what caused the sudden, unexpected death of a Beluga whale on Thursday.
The average life expectancy of a Beluga whale is 35 to 50 years.
Maris gave birth to two calves - one just last spring - but neither of them survived.
Now the community is reacting to the unusual death and some are saying the whales belong in the ocean.
This has come up before. The Georgia Aquarium has lost other Belugas as have the handful of other aquariums across the country who have them.
They are one of the most popular exhibits in Atlanta but some animal rights groups said they're not in an ideal environment.
It looked like a typical busy Friday at Georgia Aquarium but there was grief both inside, among staff members, and outside as tourists heard the news.
"That's so sad," one visitor said. "It's sad because the exhibit's great and aquarium's great."
But some are questioning this popular exhibit.
Martha Brock is a member of the group known as Georgia Animal Rights Protection (GARP) - and a former aquarium volunteer.
"It was actually the Belugas that brought me to volunteer," she said. "As you may recall, the first two - Gasper and Niko - were rescued from horrible conditions and so at the time I looked at the Georgia Aquarium as a sort of rescue."
Brock now believes the whales don't belong here.
"I began realizing that concrete tanks even as large as the ocean exhibit are not large enough for marine creatures," Niko said.
Five Belugas have died at the aquarium since it opened in 2005: Gaspar, Marina, two calves and now Maris.
Several animal rights groups have criticized Belugas being put on display.
On Friday, some downtown visitors were ambivalent.
"I don't know how I feel about that because if they're out in the ocean, you can't really see them," Greg Thompson said.
It's a dilemma for many. They enjoy observign those beautiful, seemingly smiling creatures yet wonder if they'd be better off in the wild.
11Alive asked the aquarium for a comment on Friday but they said they were grieving a very difficult loss and not doing interviews.
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