The CEO of the Vancouver Aquarium is vowing to fight back hours after learning that the Stanley Park facility will no longer be able to house whales, dolphins and porpoises.

The Vancouver Park Board voted six to one on Monday night in favour of a bylaw amendment that bars new cetaceans from the property, a decision that came into effect immediately.

Three cetaceans currently living at the aquarium – a false killer whale, harbour porpoise and white-sided dolphin – have been grandfathered in and will remain on display, but all shows or performances involving the animals were ordered to cease. The aquarium cannot bring in any other cetacean for public display or performance.

After what park board staff and aquarium CEO John Nightingale both called an emotionally charged evening, the result of the vote was "hugely disappointing" to staff.

Nightgale said he was amazed by the outpouring of support, estimating that between 400 and 500 people had shown up to the meeting and to a protest held outside the venue beforehand.

"That part was amazing and heartwarming and I just can't imagine having stood there for two-and-a-half hours in that rain last night only to be disappointed by local politics," he told CTV News on Tuesday.

Under a sea of umbrellas, a large crowd of supporters formed early in the evening, and stayed through to the vote shortly after 9 p.m. Many managed to squeeze into the meeting venue itself, mingling with other members of the public who sided with the majority of the board.

Protest at Vancouver Aquarium

The crowd erupted in cheers and boos, and had to be shushed by board chair Michael Wiebe several times during the night.

"You could feel the passion," Wiebe said following the vote.

"We could hear the people outside on both sides, front and back door, people around the gardens. We had a full gallery of people that were here (Monday) and we've seen this throughout the process."

Calling it a "tough decision," Wiebe said he was happy with the research the board's commissioners did before reaching a verdict.

Wiebe and fellow commissioner Catherine Evans both spoke Monday about the backlash they've received, something Evans referred to ahead of casting her vote as "fearmongering." She said commissioners have been accused of being heartless or ignoring science, something echoed by other members during the meeting.

Only Commissioner Erin Shum said she didn't support the ban, and had concerns about the implications of the decision on whales in distress in the future.

The concerns Shum voiced are similar to Nightingale's, who said he fears the decision will be a death sentence for rescues who are not suitable for re-release.

The park board has said that its decision should not affect the aquarium's Marine Mammal Rescue Centre, which is not housed on park property and therefore not under its jurisdiction. Several commissioners said Monday that nothing is stopping the aquarium from rescuing and treating cetaceans in need, and that if they cannot be re-released, it is not up to the board to say they can't live out their days at the research facility. The vote only affects whether whales and other cetaceans can be put on public display at the aquarium in Stanley Park, which is the city's most popular tourist attraction.

But Nightingale said that the rescue and research campus is like a hospital for marine mammals.

"Just like humans, you go to the hospital, you get well, you go back to your normal life, or you need long-term care sometimes. For 50 years, the aquarium has been that long-term care," he said.

He did not provide specifics of what staff hope to do next, but said: "We're going to continue our fight to save the ability to rescue animals."

The park board is an elected body, so there is a possibility that a new board could reverse the decision. The aquarium also isn't ruling out a legal challenge.

Many have suggested staff build a new facility with larger tanks, somewhere outside of the park board's Vancouver jurisdiction, but he said that would cost another $20 million, and $2 to $3 million to operate each year, a costly venture that Nightingale suspects local politicians would not approve.

Aquarium CEO John Nightingale

Nightingale said the decision is fresh and staff members are still deciding what to do – particularly about a $20-million Arctic exhibit the aquarium had planned, which was previously green-lit by the park board. Construction hasn't started, but the aquarium hoped to have it up and running within two years. The exhibit, which would be home to belugas brought in to replace the mother and daughter that died in November, would stay open until the end of the aquarium's lease in 2029.

The new display was to be three times the size of the current one, Nightingale said, and could fit up to five non-breeding whales.

Nightingale said the 12 years would buy staff time to come up with a new plan, that would include where to house any whales off-campus and how to continue to educate the public without its beluga shows. He said the aquarium is "not going to go away," but staff are still considering the impact of the decision and how to deal with it.

Commissioner Sarah Kirby-Yung said Monday that while she commended the aquarium for making a suggestion, where staff and the board differed was the timeline. Most members did not feel that $20 million should be spent on an exhibit which may only be open for 10 years, especially when there are no belugas currently living at the facility.

But although the aquarium has not housed any belugas since its residents died of an unknown toxin, it does own five belugas currently on loan to other facilities. Nightingale said they've started conversations with those currently caring for the whales, but they aren't sure yet what will happen to them. The intention was they'd be brought back to the aquarium when the new exhibit was finished in the spring of 2019.

"Park board says, 'We don't care, it's your problem.' Well, it is our problem. We have a moral obligation to those animals," he said.

The board has said that it continues to support the "excellent work" being done by staff and volunteers at the rescue centre near Crab Park. Wiebe said the decision was based on "extensive" input from the public, discussions with aquarium staff and a review of best practices from aquariums around the world.

The amendments approved Monday are expected to minimally impact its rescue and rehabilitation program, the board said, as most of its rescued animals are harbour seals.

In a statement, the board said the aquarium ended the display of orcas in 1996.

"We anticipate that the aquarium will manage all future cetacean rescues in the same manner they handle the rescue of orcas," the statement said.

The BC SPCA applauded the decision, saying in a statement on Tuesday that it was a "significant move forward for animal welfare."

The organization's chief scientific officer Sara Dubois said: "As humans we know that confinement and social isolation in small indoor spaces without any control over our environment is emotionally damaging for our well-being."

She said research has emerged in the last three decades that having enough diverse space is a "very basic requirement" for cetaceans' psychological wellbeing.

Dubois said the SPCA has been supportive of the aquarium's marine mammal rescue work, and doesn't believe that a ban on displaying cetaceans will impact its efforts.

"The mammal rescue work is done offsite and is a small fraction of the aquarium's $60-million budget," she said.

She added that other rescue facilities, like the BC SPCA's Wildlife Animal Rehabilitation Centre in Metchosin, do not put rescued animals on display, and that doing so with the aquarium's three remaining cetaceans does not have anything to do with their welfare needs.

"If the aquarium believes their rescue program – which mainly treats non-cetaceans like harbour seals – is in jeopardy without cetaceans on display, the BC SPCA is more than willing to work with them to find a long-term solution for this important work," she said.

With files from CTV Vancouver's Nafeesa Karim and Sheila Scott