A Canadian filmmaker has disappeared after a deep dive in Florida waters that left his partner unconscious, according to the missing man's sister.
Rob Stewart, 37, was in Florida filming a documentary called "Sharkwater: Extinction" when the incident happened, his sister, Alexandra Stewart, said Wednesday.
She said Rob Stewart and a dive instructor returned to the surface near Alligator Reef off the coast of the Florida Keys around 5 p.m. Tuesday.
"The other diver got on board and was struggling to get on board and then fell unconscious," she said. "Rob gave the OK signal to the boat, but as the other diver fell unconscious, there was a commotion around that on board and the boat lost sight of Rob."
Stewart's sister said there's a concern her brother lost consciousness as well.
The dive was her brother's third one of the day, she said, noting that he and his instructor had gone down about 70 metres.
The family is in shock, she said.
"I'm doing terribly, we all are, but we have hope."
She said her parents and her husband are in Florida helping manage search efforts, but they still need those with experience to join the search that is being co-ordinated by the U.S. Coast Guard.
Coast Guard senior chief Nyx Cangemi said crews had been looking for the conservationist since he was reported missing.
"As long as there's a chance of survival, we're going to search," Cangemi said in an interview. "We remain hopeful that we'll be able to find him alive."
Cangemi said the emergency call about Stewart came from the crew of the Pisces, the boat the filmmaker had been on.
He said the search for Stewart included boat and helicopter crews. The U.S. Navy, the Florida Fish and Wildlife Conservation Commission and the Monroe County Sheriff's Office are also helping.
Stewart, a Toronto native, is known for his documentaries that include "Revolution" and his memoir "Save the Humans."
A global wildlife photographer, Stewart has devoted his career to warning the world about threats facing sharks, other ocean life and humanity in general.
His 2006 documentary "Sharkwater," which debuted at the Toronto International Film Festival, became an international hit and prompted people around the world to lobby their governments for bans on shark finning.
Stewart said he and his colleagues risked their lives to make the film: they visited a Costa Rican warehouse that trafficked in illegal shark fin and confronted poachers on the high seas.
Stewart shot "Revolution," which came out in 2012, in 15 countries over four years.
"This century we're facing some pretty catastrophic consequences of our actions," he said in a 2012 interview with The Canadian Press.
"We're facing a world by 2050 that has no fish, no reefs, no rainforest, and nine billion people on a planet that already can't sustain seven billion people. So it's going to be a really dramatic century unless we do something about it."
