Chester, a false killer whale, and his companion, Helen, a Pacific white-sided dolphin, have their eyes on their trainers and the red tubs of fish on deck.
Helen pops her head out of the water and lets loose a chatter. With a flick of her trainer's hand, Helen is airborne, her body curved in a perfect arc, five metres above the water.
Then it's Chester's turn. The false killer whale – a type of dolphin – leaps on command, landing his 225-kilogram bulk with a mighty splash.
In the front row, watching and smiling, six-year-old twins Caprice and Lincoln Hoelzler risk getting wet.
Chester and Helen are the rock stars of the Vancouver aquarium. Both were rescued – Chester from the Chesterman Beach on Vancouver Island where he washed ashore as a newborn in 2014, and Helen from a fishing net off the west coast of Japan in 1996. They were nursed back to health but deemed unable to be released to the wild by Department of Fisheries and Oceans evaluators.
Today, they are the only two cetaceans (whales, dolphins and porpoises) on display at the aquarium in the heart of Stanley Park. Last week, Daisy, a harbour porpoise rescued by the aquarium in 2008 when she was only a month old, died. The cause is not yet known.
Chester and Helen may be the last cetacean residents at the aquarium if a Vancouver Park Board decision last month to ban the importation and display of cetaceans survives court appeals.
And they represent the centre of an international debate over the scientific benefits of having cetaceans in captivity, the ethics of such displays and the emotional connection between the creatures and the humans who want to visit, study and protect them.
Is the potential harm to whales and dolphins confined in a pen outweighed by the love of nature they instill in their human audience, or the value of research conducted by their keepers? And given the only cetaceans currently on display in Vancouver were rescued, would it be better to have let them die than relegate them to life in an aquarium pool?
Earlier this month, the Vancouver Aquarium asked for a judicial review aimed at overturning the park board ban.
Meanwhile, a private member's bill in Ottawa to end the captivity of whales and dolphins countrywide is slowly winding its way through the Senate, but is unlikely to become law.
Vancouver was the first aquarium to display an orca in 1964 but also the first in the world to stop capturing wild cetaceans in 1996. Bjossa, the aquarium's last orca, was sent to SeaWorld in 2001.
But as aquariums elsewhere in North America and Europe have concluded they will not keep cetaceans in captivity, John Nightingale, the Vancouver Aquarium's president and CEO, continues a passionate defence of the aquarium's ability to harbour rescued cetaceans that cannot be released into the wild.
On a day in mid-May, he has just exited a strategy meeting on how to counter the new park board bylaw. Often suave and unflappable when working a room for a cause, his brow is now furrowed and he looks stressed. The more urbanized we become, the more difficult it is to connect with nature, Dr. Nightingale says.
"If you're going to try to light that little flickering flame of curiosity and awareness and fan it a bit, living animals are an amazingly effective way to do that.
"It's no accident that most elementary teachers have a rabbit, or guppies or guinea pig in the classroom."
But Annelise Sorg of No Whales in Captivity, one of the most vocal groups opposing the aquarium, doesn't buy it. She maintains in an interview with The Globe and Mail that modern hologram shows, in use in the Dubai Mall, where the aquarium has no cetaceans, are so realistic, they elicit the same emotions.
"Kids are nuts about dinosaurs, and who's ever seen one?"
The bylaw was passed by the parks board in May, six months after Aurora and Qila, the aquarium's last two beluga whales, died of an unknown toxin.
The deaths elicited a public mourning for the ethereal belugas who were so beloved the aquarium routinely sold out sleepover parties in their viewing room. It also injected new steam into a decades-old campaign to ban captive cetaceans.
Animal-rights activists capitalized on the deaths and cranked up the pressure on the park board to enact the ban.
Cornered, Dr. Nightingale, who had planned to bring back some of Vancouver's belugas on loan to other aquariums, tried to buy time with a "compromise" position. He volunteered to phase out belugas by 2029 to adjust to the loss of revenue that would inevitably arise from having no whales.
But he continues to defend cetacean displays on the value of scientific research and education and is threatening to challenge the bylaw in court.
Dr. Nightingale is upfront about the importance of the cetacean displays to the aquarium's bottom line. Without them, "the aquarium will survive, but it's going to be diminished," he says. "Even a 10-per-cent drop in attendance means $4-million that won't be spent on conservation and research because fixed costs like hydro to heat the tanks, will still have to be covered. Cuts will have to come from education programs that make the aquarium a world leader," he says.
Money is the indelicate side of the argument.
There is also a more nuanced, ethical debate over whether cetaceans should ever be held captive.
Humans have long been entranced by cetaceans. Of all the ocean mammals, they most closely resemble ourselves. They have large brains, live in extended family clans and vocalize to communicate. They also exhibit behaviour that in human terms can only be described as loyalty. An orca mother and her offspring stay together for life. If a Pacific white-sided dolphin is sick or injured, its podmates stick by its side.
In the wild, cetaceans cover vast distances: Orcas can swim up to 160 kilometres per day and belugas can dive more than 700 metres deep in search of food.
Dr. Nightingale says without the aquarium's large pools, the Marine Mammal Rescue Centre run by the aquarium on port land will have nowhere to discharge rescued cetaceans that cannot return to the wild.
"Fisheries and Oceans has said if you don't have a long-term home, you probably shouldn't rescue them to begin with. So, the answer is, 'Well, they can die a slow, painful death on the beach, or the DFO enforcement officer is going to put a bullet in him.' "
Rebecca Ledger, a Vancouver-based animal behaviourist, chides Mr. Nightingale for using that "shock tactic," but eventually concedes the point: If it is impossible to give an animal enough space to lead "a life worth living," she says, it is better to let it perish.
Andrew Trites, a professor and director of the University of British Columbia's Marine Mammal Research Unit, which works closely with the aquarium, disagrees.
If the aquarium can give good care to an animal unable to survive in the wild, there is nothing wrong with keeping it in captivity to serve as an educational "ambassador" for its species, he says.
Mr. Nightingale defends cetacean displays on the grounds the animals are happy, well-fed, have stellar veterinary care and plenty of mental and physical stimulation.
Dr. Ledger, whose studies included cetaceans and who spent considerable time observing Qila and Aurora before they died, believes otherwise. Although it's hard to tell whether an animal is happy, there are telltale signs of anxiety or depression.
Animals that pace back and forth or chew the cage bars – behaviours scientists call locomotor stereopathy – are suffering emotionally, and Dr. Ledger says she observed this in the belugas.
They adopted a relentless, repetitive pattern, she says.
"They were swimming in circles. Now you might say, what else can they do in a tank. But they had a ritualized route."
Dr. Ledger wants more attention paid to the emotional well-being of cetaceans. Large, open sanctuaries might alleviate the distress, she says.
"I'm not saying we should shut down the aquarium. But I do believe … they need more space."
But what if the research conducted on captive cetaceans is crucial to their survival in the wild?
Here, too, the scientific community is split, and the discourse can get nasty and personal.
Some argue captive animal research is invaluable; others say it does not translate to the wild where conditions for survival are so different.
Valeria Vergara, a research scientist at the Vancouver Aquarium, says having the belugas on site allowed her to study mother and calf communication in a unique way.
On her computer screen are rows of audio files charting echolocation (communication) between the beluga calf and its mother.
Dr. Vergara says because the animals were captive, she could eavesdrop as the calf developed its "hello" call, communication vital to the animals' social cohesion. In a wild pod, too many other whales are around to identify which one is calling, she says.
The research could prove vital at a time when whale communication is threatened by noise from increased ocean traffic.
"They are being bombarded by deafening levels of underwater noise, not just belugas but also resident killer whales," Dr. Vergara says.
This research could help the case for noise mitigation, she adds. When the aquarium's belugas died, Dr. Vergara shifted her studies to wild populations.
But many scientists argue that most, if not all, meaningful research takes place in the wilderness.
A 2016 research review commissioned by the Vancouver Humane Society and Zoocheck entitled A Crumbling Case for Cetacean Captivity? catalogued all the peer-reviewed research papers arising from captive cetaceans at the Vancouver Aquarium and Marineland Canada in Niagara Falls, Ont.
Each paper was judged by the number of times it was referenced by others – more references indicate fellow scientists consider the material important. The study also examined how many papers pertained to wild cetaceans.
It found 13 peer-reviewed papers from research on captive cetaceans at the Vancouver Aquarium over the past 30 years. Most were not widely cited, the exception being studies on beluga hearing, the report states. As well, four of the papers had no application to wild animals.
The review concludes that, while research on captive cetaceans "may make a small contribution to the overall pool of knowledge about these animals, many captive studies seem to have no substantive or direct conservation value."
The aquarium dismisses the study as "biased" and questions whether true scientists reviewed the research.
(The review was authored by Lori Marino, who has a PhD in Psychobiology and Animal Behavior and has studied marine mammals for more than 25 years.)
UBC's Dr. Trites says some scientists so oppose captivity they are blind to the value of research done on captive cetaceans. He says about a third of what is known about cetaceans has come from captive animals.
"You can't learn everything watching from a boat."
Whether or not the scientific arguments for captivity are valid, the Vancouver Aquarium's campaign to keep its cetaceans is bucking a European and North American trend to stop displaying them in aquariums.
Orcas were first on the activists' radar, says Lori Marino, a neuroscientist and animal behaviour expert from Utah who leads the Whale Sanctuary Project, which aims to open a large open ocean sanctuary somewhere in North America.
Even San Diego's SeaWorld, which is more theme park than research facility, announced last year it would stop breeding orcas and phase out the shows when existing stocks die.
Dr. Nightingale still believes orca displays are acceptable, provided an aquarium has enough space. He now believes the Vancouver Aquarium does not, and given it is in Stanley Park, it is unlikely to expand, he says.
Although he no longer lobbies for keeping orcas, Dr. Nightingale says there is enough room at the aquarium for smaller cetaceans.
The only two places in Canada that currently display cetaceans are Vancouver and Marineland.
Further afield, France adopted legislation in May to ban capture or breeding of cetaceans. The National Aquarium in Baltimore is moving its bottlenose dolphins to a larger outdoor sanctuary. And aquariums in Seattle, Maui and Monterey thrive with no cetaceans whatsoever.
Monterey made a conscious decision not to include cetaceans. It is viable financially and is a stellar research facility, Dr. Marino says.
"Others will follow. It's definitely the way things are going in the West and in Europe," she adds.
In Asia, though, cetaceans are still being captured in the wild to fill a growing number of aquariums in China. Animal welfare advocates are lobbying to end the practice in Russia, China and South America but haven't had much traction yet.
While hard-core activists would eventually like to close all aquariums, the momentum seems to favour those like Dr. Marino pushing for larger facilities.
Dr. Marino wants the Vancouver Aquarium to partner with her group to build an ocean whale sanctuary. Dr. Trites and Dr. Nightingale say the idea might sound great, but isn't practical. "Where would we do that? Who would pay?" Dr. Trites wonders.
For Ms. Sorg, and other hard-line activists, the end goal is different.
When pushed, she admits her ideal would be to shut down all zoos and aquariums. Right now, however, the fight is only about whales, dolphins and porpoises.
"It will take us another 20 years to get the public to have compassion for smaller marine mammals. As activists, we don't want to waste our time either."
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