Mary Tyler Moore (search) has been pecking at her co-op board and neighbors for evicting the renowned hawks from her posh Fifth Avenue building — but yesterday they crowed back, accusing her of orchestrating the pro-bird campaign as a personal vendetta.

"She has a big ax to grind," said a board source. "A lot of her activism is bent on vengeance after the co-op board turned down a potential buyer for her apartment."

Moore was the most vociferous of the residents of 927 Fifth Ave. to oppose the board's decision to take down Pale Male and Lola's nest, even joining the protesters in their spirited picket line.

The sitcom pioneer has two apartments that have been on the market since the summer; one on the eighth floor for $18.5 million, and a first-floor studio apartment — used primarily as an office by her husband, Dr. Robert Levine — for $2 million.

Moore was thrilled when she found a buyer willing to pay roughly more than $2 million over the asking price for the eighth-floor residence.

But the potential purchaser, a Russian citizen, was perceived by the board to be a person of questionable reputation.

"She tried to push someone on the co-op board that no co-op board in the city would've accepted," said another building insider. "He traveled with bodyguards. He was just what you don't want in a family building."

The 12-story prewar building is populated mostly by families with children. During a co-op board meeting about six weeks ago, the applicant for Moore's apartment was turned down in a quick and decisive vote.

"Mary went ballistic," said the board source. "It was a messy turndown."

Neighbors said Moore was overheard ranting that co-op chairman Richard Cohen, husband of CNN anchor Paula Zahn, had personally put the kibosh on the applicant.

She also didn't make any friends when she initially defended the man who was arrested for allegedly threatening the couple's children — although it was before she knew the severity of the charges.

"She's trying to be this virtuous Mary Richards," the board source said, referring to her sugar-sweet classic-TV character. "But she hasn't worked in ages. She just needs the money. And if she loves the hawks so much, why is she leaving?"

A spokeswoman for Moore denied her concern for the birds was just an act.

"She has always been an advocate for animal rights," said Mara Buxbaum. "So it is not out of character for her to be against the removal of the Pale Male nest."

For more news, entertainment and sports coverage, click here for NYPost.com.