By MICKEY MEECE

Yelling, scheming and sabotaging: all are signs that a bully is at work. During this downturn, as stress levels rise, workplace researchers say, bullies are likely to escalate their attacks.

It’s probably no surprise that most of these bullies are men, as a United States survey by the Workplace Bullying Institute, an advocacy group, makes clear.

But about 40 percent of bullies are women. And the women appear to prefer their own kind, choosing other women as targets more than 70 percent of the time.

Women don’t like to talk about it because it is“so antithetical to the way that we are supposed to behave to other women,”said Peggy Klaus, an executive coach in Berkeley, California.“We are supposed to be the nurturers and the supporters.”

Ask women about clashes with other women at work and some will point out that people of both sexes can misbehave. Others will nod in instant recognition and recount examples of how women - more so than men - have mistreated them.

“I’ve been sabotaged so many times in the workplace by other women, I finally left the corporate world and started my own business,”said Roxy Westphal, who runs the promotional products company Roxy Ventures Inc. in Scottsdale, Arizona.

Jean Kondek, who recently retired after a 30-year career in advertising, recalled her anger when an administrator in a small agency called a meeting to reprimand her in front of co-workers for not following agency procedure in a client emergency.

But Ms.Kondek said she pushed back.“I said,‘Would everyone please leave,’and then I told her,‘This is not how you handle that.’”

After decades of striving for equality, women make up more than 50 percent of management, professional and related occupations, says Catalyst, a nonprofit research group. And yet, its 2008 census found, only 15.7 percent of Fortune 500 officers and 15.2 percent of directors were women.

Leadership specialists wonder, are women being“overly aggressive”because there are too few opportunities for advancement? Or is it stereotyping and women are only perceived as being aggressive? Is there a double standard at work?

Research on gender stereotyping from Catalyst suggests that no matter how women choose to lead, they are perceived as“never just right.”What’s more, the group found, women must work twice as hard as men to achieve the same level of recognition and prove they can lead.

“If women business leaders act consistent with gender stereotypes, they are considered too soft,”the group found in a 2007 study.“If they go against gender stereotypes, they are considered too tough.”

Bullying involves verbal or psychological forms of aggressive (hostile) behavior that persists for six months or longer. The Workplace Bullying Institute says that 37 percent of workers have been bullied.

Two Canadian researchers recently set out to examine the bullying that pits women against women. They found that some women may sabotage one another.

One of the researchers, Grace Lau, a Ph.D. candidate at the University of Waterloo, said the goal was to encourage women to help one another. She said:“How- One way we predicted would be to remind women that they are members of the same group.”

In the workplace, however, it is unlikely that women will constantly think of themselves as members of one group, she said.

“As a result, women may not feel a need to help one another,”she said.“They may even feel that in order to get ahead, they need to bully their coworkers by withholding information like promotion opportunities, and that women are easier to bully than men because women are supposedly less tough than men.”