Mike Holmes says he's heard the criticism about animal cruelty at the Calgary Stampede, but he's still proud to be this year's parade marshal.

Holmes, the construction contractor best known for his TV program "Holmes on Homes," says he's aware that "the Greatest Outdoor Show on Earth" faces criticism every year about how it treats the animals in its bull and bronco riding events and races.

"That's the number one question that has been thrown my way since I've been here," Holmes told Canada AM from near the parade start line in Calgary Friday.

"Yeah, I'm hearing it. But what I see is that they are hooked up with the [Calgary] Humane Society, they care very much about the animals."

The Humane Society of Canada sent an open letter to Holmes on June 17, asking him to reconsider accepting the position of marshal for Friday's parade that officially kicks off the Stampede.

"Rodeos are nothing more than a brutal violent spectacle," the letter read. "They pit people and animals against one another in open conflict to provide bored city dwellers with cheap thrills."

The letter noted that numerous animals have been killed or severely injured at the Stampede, including one horse that was euthanized following a collision in the Chuckwagon event at the 2008 Stampede and three horses that were killed in a collision during the Rangeland Derby at the 2007 Stampede.

"Mr. Holmes, you have a well-deserved and hard-earned reputation as a gentle and fair man, and we would respectfully ask that you not lend your credibility and endorsement to these kinds of activities," the letter asked.

Holmes told CTV Calgary he only heard about the letter on Thursday. He told Canada AM he's not here to judge Stampede ethics but to have a good time and enjoy his first Stampede.

"I see nothing but a positive thing here. I don't want to knock it because I'm here to support everyone who believes in the right thing. And right now we're doing the right thing and that's doing the Stampede," he said.

The Stampede says it works with the Alberta SPCA and the Calgary Humane Society to ensure the safety of livestock used in its events.

"We know what we do for the welfare of the animals and all the animals on the park," Stampede spokesman Doug Fraser told CTV Calgary. "We know the care we give these animals and the passion we have for them."

The Humane Society of Canada is not giving up and is asking the country's broadcasting watchdog to phase out the airing of the 10 days of Stampede events.

The Human Society believes rodeo events violate the Canadian Radio-television and Telecommunications Commission's own code by glamorizing cruelty to animals during programming.

The CRTC has not offered an official response.