Gendron, who moonlights as a shock job on Radio X told listeners about the methods he employs to get rid of stray cats, which he calls a nuisance, the Canadian Broadcasting Corp. reported Monday.
"If a stray cat is in the street, BANG, I accelerate," he said.
"The other day, I backed up over one that had just come into the world. I'm sure it didn't feel anything. I was very happy. Yes!" he added.
Gendron issued an open letter apologizing for his words, saying he intended them to be perceived as black humor though he didn't clarify whether they were true, the CBC said.
This isn't the first time Gendron has been in hot water for making controversial statements.
He made anti-Israel comments in 2012 and violated the broadcasting code of ethics in 2006 for comments he made about a child pornography case.
Montreal SPCA spokeswoman Alanna Devine said Gendron's comments are "really very disturbing to hear."
"Those comments and supposed acts coming from somebody -- from anybody, but particularly from someone who is a public figure and an elected official of a municipality," she said.