A Toronto filmmaker who was found dead days after he went missing while diving off the coast of Florida is being remembered as a "warrior" for environmental rights.

Rob Stewart's body was found Friday, 90 metres from where he disappeared on Tuesday.

In a video posted to Facebook, Tyler MacLeod, who was listed as an associate producer on one of Stewart's films, said the director was an inspiration.

"Rob literally never flinched. He never changed. He's always been a warrior for this planet and a warrior for what's right," MacLeod said in a video posted to Facebook after Stewart's body was found. "At least in my mind, he's a massive hero."

Stewart had been diving with friends on Tuesday when he was last seen. They were diving deep -- about 70 metres down, which the coast guard said is deeper than many people are able to go -- near Alligator Reef in the Florida Keys.

His diving partner lost consciousness as he got into the dive boat, Stewart's sister previously told The Canadian Press. Coast Guard Capt. Jeffrey Janszen said that as others tended to the man and gave him oxygen, Stewart disappeared.

In the wake of his disappearance, support flooded in for the missing filmmaker. Nearly $200,000 had been donated to an online fundraising page for the search for Stewart by Saturday. MacLeod, who organized the page, said any leftover money would be given to Fin Free, a charitable organization that works for the protection of sharks.

Toronto mayor John Tory said on Twitter that Stewart's death was not the news he was hoping and praying for.

"My heartfelt sympathies go out to family and friends of .RobStewart," he wrote.

Others also took to social media to memorialize Stewart, including Paul Watson, president and CEO of conservation group Sea Shepherd.

On his Instagram account, Watson posted a statement offering condolences to the filmmaker's family.

"He accomplished so much in his 37 years," Watson wrote. "We will miss him and we intend to honour his life by working to protect and defend the sharks that he loved so much."

"He knew the risks involved with his work and told me once that sharks were the least of those risks," he added.

Watson appeared in the film for which Stewart was best-known: "Sharkwater."

The documentary debuted at the Toronto International Film Festival and became an international hit. It prompted people around the world to lobby their governments for bans on shark finning.

He had been in Florida filming a follow-up movie to the 2006 documentary called "Sharkwater: Extinction," his sister said.

He devoted his career to warning the world about threats facing sharks, other ocean life and humanity in general.

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.

"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."