A special meeting to discuss the future of whales in captivity at the Vancouver Aquarium will stretch into a second evening Thursday night.

More than 60 people signed up to speak at the Vancouver Park Board special meeting, but on Wednesday night they managed to only get through a portion of the speakers on both sides of the issue. Park board commissioners spent 70 minutes grilling aquarium staffers on their cetacean program.

The board is looking at four different options: banning captive cetaceans outright, having a plebiscite on the Vancouver civic vote in 2018, or going ahead with the Vancouver Aquarium's planned expansion of its beluga facilities.

The final option being weighed is keeping things status quo, although a board report says the option does not address the growing public sentiment against keeping cetaceans in captivity – and could invite backlash from protesters and special interest groups.

The park board and city have received hundreds of letters, calls and emails on both sides of the debate since the recent deaths of the aquarium's beluga whales.

Qila and Aurora died within weeks of one another in November 2016. They likely died of a virus or toxin, although $100,000 in testing has not yielded a definitive answer.

The aquarium has voluntarily agreed to stop breeding beluga whales at its facility and says it will phase out whale displays altogether by 2029.

However, the aquarium is still planning to incorporate three to five new cetaceans in its new Arctic Exhibition starting in 2018/2019 "as part of its on-site conservation research program."

After this week's debates, park board members will vote on which option it prefers and have staff investigate and come back with the best implementation methods.