Canadian filmmaker Rob Stewart missing after Florida dive, sister says time is 'critical'

Torontofilmmaker and conservationist Rob Stewart is missing after a Tuesday night dive off the coast of Florida.

The U.S. Coast Guard is on the scene Wednesday morning to search forStewart, 37, who vanished while diving near Islamorada in the Florida Keys, a chain of islands between the Atlantic Ocean and Gulf of Mexico, located nearly 200 kilometresoff the state'ssouthern tip.

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"We're in the critical window of daylight right after he's gone missingwhere, if we're going to find him on the surfacewhere we'd like to find himit's going to be today,"Stewart's sister, Alexandra Stewart, said in an emotional interview with CBC Toronto on Wednesday morning.

The family has also launched a GoFundMe campaign to mobilizemore resources to help with the search, she said.

Stewart is best known for his 2006 documentary Sharkwater, an examination of global shark-hunting and its impact on the ocean ecosystem, and was active in underwater filming.

His sister said his latest dive was part of work on the film's upcoming sequel, Sharkwater: Extinction.

Jeremy Weaver, senior chief of the U.S. Coast Guard, told CBC Toronto that ahelicopter from Miami, a boatand a team of divers are involved in this morning's search.

Weaver said Stewart was "diving on a wreck off ofIslamorada" with three other divers when he went missing, but the three are safe.

Not clear why Stewart disappeared

Stewart "resurfaced at the end of the dive, and as the boat was turning around to pick him up, he went back under and was not seen again," Weaver said.

It's not immediately clear what caused Stewart to go back under water, but his sister said it was a"particularly difficult" dive, going to a depth of nearly 70 metres.

She said her brother may have lost consciousness after doing a third dive that day.

"It's extremely rare that even experienced divers are qualified to do that kind of dive," Stewart's sister said.

"The other fellow who was on the samefinal dive appears to have lost consciousness when he surfaced, so it might have been too much diving in a certain window. It's hard to speculate."

Weaver said weather conditions were good at the time of the dive early last night.

MichaelParfit, an environmental writer and filmmaker based in Vancouver, saidStewart routinely takes risks while diving because he hasbeen "so driven to know these animals and transmit what he knows to the public."

A deep dive comes with potential dangers, said Parfit, but it's "nothing unusual."

Family in Florida asvolunteer help sought

Stewart's sister, who is currently in Toronto, said the siblings' parents and her husband are in Florida right now and in constant contact with search teams.

"If there are other people out there, what we desperately need are more surface searchers," she said.

Alexandra Stewart

8 years ago

Duration 1:11

Canadian filmmaker Rob Stewart missing after Florida dive, sister says time is 'critical'

Stewart's sister stressed his love for the environment, something evident in his work as a filmmaker.

"He has a deep love forthe ocean, and wildlife, and our planetand people, and trying to make the world a better place," she said, her voice breaking.

"And he really saw this as where he could make his unique mark, and I think we've seen that over his life. What he's done for shark finning and illegal fishing has been tremendous."

Dustin Titus, who has known Stewart for more than a decade, also praised his passion for conservation.

Stewart's work resonates "around the globe," said Titus, a member of the board of directors for the United Conservationists Society of Canada.

The conservation community is experiencing"a lot of nervousness" over Stewart's disappearance, he added."Everyone's really scared."

Stewart's films have won dozens of awards

Sharkwaterpremiered at the Toronto International FilmFestival and has since won more than40 awards at film festivals around the world.

Stewart's second film, Revolution, was the highest-grossing Canadiandocumentary in 2013 and won 19 awards from global film festivals.

Stewart was born and raised in Toronto, and studied biology at Western University in London, Ont.

He is also considered one of the "distinguished alumni" ofToronto's Crescent School, which he attended from grades 7to 9, and where he has since returned to speak to students about his work in marine conservation.

"Our thoughts are with Rob's family and we share their hope for his safe return," the school said in a statement.

"We are looking forward to having him back because the world needs him," echoed Parfit.

"The sea, the oceansneed him."