The latest death of a baby beluga at the Vancouver Aquarium on Monday night has renewed critics' calls for a public vote on whether to stop keeping whales at the facility.

Jonash Mate of the group No Whales in Captivity says Vancouverites should be given a chance to weigh in on the issue in the form of a plebiscite during the next civic election.

"Add another question onto the ballot: are you in favour of phasing out the captivity of cetaceans in the Vancouver Aquarium?" he said.

Officials say Nala, the aquarium's youngest beluga, likely died when her airway was obstructed by inflammation from two rocks and a penny that were lodged in a unique pocket branching off from her airway.

Nala was born to the aquarium's 20-year-old beluga Aurora in June 2009. She was described as an energetic, curious, and sociable calf.

Three of the five baby belugas born at the aquarium have died. Aurora's male calf Tuvaq died in 2005, three years after being born.

Brian Sheehan, curator of marine mammals at the aquarium, said research shows the survival rates of calves in captivity is 40 to 50 cent in the first year. He said survival rates in the wild would be about the same because belugas deal with a harsh environment and predators.

But critics still charge that captivity is inhumane, and question the educational benefit for visitors of viewing whales up close.

Vancouver park board commissioner Loretta Woodcock pushed for a plebiscite in 2005, but her motion was ultimately shelved. Board chair Aaron Jasper says a vote would have little effect, because the aquarium has a 20-year contract stating captivity bylaws will not be reviewed until 2015.

Woodcock says the vote would still give aquarium officials a chance to gage public opinion. "The aquarium likes to keep up with the public interest," she said.

With files from CTV British Columbia's Maria Weisgarber and The Canadian Press