In a unanimous vote, the Vancouver Park Board has decided to change its bylaws to end the display of live cetaceans at the Vancouver Aquarium.

The Thursday night vote came at the end of a lengthy, emotional debate that spanned two nights and heard from more than 60 speakers.

Ultimately, all seven commissioners voted in favour of a motion to amend bylaws "to prohibit the importation and display" of live cetaceans — porpoises, whales or dolphins — at the aquarium.

Park board staff will report back to enact the amendment in mid-May.

Several board members said the recent deaths of two beluga whales at the Stanley Park facility swayed their votes.

Aurora, 30, and her calf Qila, 21, died within nine days of one another last November, after signs of illness. No clear cause of death was ever determined, although aquarium staff said they expected toxins in the water were to blame.

"There are times when there are tipping points in life," said Commissioner Sarah Kirby-Yung, calling the animals' deaths an "incredibly sad loss."

"If there is going to be a change, now is the time to do it."

<a href="https://twitter.com/hashtag/VanParkBoard?src=hash">#VanParkBoard</a> votes to direct staff to bring forward bylaw change by May 2017 prohibiting display of cetaceans at Vancouver Aquarium. <a href="https://t.co/Tk1MiI0ZKo">pic.twitter.com/Tk1MiI0ZKo</a> —@ParkBoard

Aquarium staff members — including president John Nightingale — were in the audience. They left quickly after the vote and declined to speak to reporters.

The special park board meeting was called to debate the future of cetaceans at the aquarium. The board had a range of options it was considering, including calling for a non-binding, city-wide plebiscite on the issue.

Another option was to accept the aquarium's plan to expand the beluga pool and bring back whales until the year 2029, although breeding would have been prohibited.

'Times have changed'

At the meeting, park board commissioners spoke with admiration of the aquarium's conservation work and its history in Stanley Park. Many talked about their childhood experiences there.

But commissioners also acknowledged that keeping large mammals in small spaces is not as humane as once thought.

"It is just time for us not to have cetaceans in captivity," said Commissioner John Coupar. "Times have changed."

There are three cetaceans currently living at the aquarium: a Pacific white-sided dolphin, a false killer whale and a harbour porpoise.