Whales and dolphins in captivity, or not? That's the issue Vancouver's park board will debate Monday night, possibly putting the fate of the aquarium's whale and dolphin exhibits in the hands of city voters.

Stuart MacKinnon, the board member behind the motion involving the Vancouver Aquarium at Stanley Park, wants to have a non-binding plebiscite on the matter when residents go to the polls next year.

"This is a motion to have a plebiscite at the 2011 civic election to ask the citizens if they are in favour of phasing out the cetacean exhibits in Vancouver parks," he said.

The hot topic being debated means the evening could stretch out for a while.

"It's the last item on the agenda and word has it the aquarium's going to put as many people on the speakers' list as possible so I'd imagine it's going to be a very long meeting," MacKinnon said with a laugh.

A zoo at Stanley Park closed for good in 1997, four years after Vancouver residents voted to shut it down.

MacKinnon is clearly on the No side when it comes to whales and dolphins being kept in pens.

He said the death of a beluga whale at the aquarium last month prompted him to consider whether now is the time to have a similar referendum on the marine facility.

Though his proposal has drawn praise from conservationists, fellow park board members aren't so supportive.

Board chairman Aaron Jasper accused MacKinnon of political posturing and putting his personal ambitions ahead of his civic duty.

"The way he's going about this is irresponsible and reckless because, rightly or wrongly, the previous board agreed not to review this issue until 2015 and the aquarium negotiated in good faith under those terms," he said.

"So our staff feel that if we were to thumb our nose at that and proceed with this plebiscite there's serious risk that we the park board and the taxpayers of Vancouver would be exposed to a lawsuit."

MacKinnon said the board can't make its decisions based on threats, especially because any number of rulings could be susceptible to some type of lawsuit and the plebiscite is non-binding.

He said the plebiscite must occur next year because under upcoming provincial rules, municipal elections will be held every four years instead of three years. That would make 2011 the final opportunity to vote before the cetacean bylaw is reviewed in 2015.

Jasper said there are plenty of ways to gauge public sentiment after the current agreement comes to an end, though he couldn't elaborate on what might work better than a city-wide vote.

He said the aquarium's educational and research work involving marine mammals makes it a valuable facility for the city.

"I feel that, personally, the good they do far outweighs the negative in terms of having whales in captivity," he said, adding the aquarium's cetaceans could not be returned to the wild.

Peter Hamilton, director of non-profit ecology organization Lifeforce Foundation, said no one wants to see the aquarium's current cetaceans released into the open waters.

The best approach would be to phase out the exhibits and not bring in any new animals, he said.

"Politicians must give the citizens of Vancouver a chance to vote on whether or not they want dolphins in captivity."

Aquarium officials declined interview requests and have said they strongly oppose the plebiscite motion, which they'll address at Monday's meeting.