Gotta come back into this, since my friend Panini said some things ... No Jeff, I'd never dream of nailing you to anything.
Right now I'm doing consulting, but I've worked in restaurants, managed a catering operation, and been the kitchen manager for a food manufacturer. In the time I worked in restaurants, I was garde manger, grillman
(yes, that's what you call it), saute, and pastry chef. In some of those kitchens I was the only woman; in some, the only woman on that shift but there was a woman Sous Chef on the other shift; sometimes there were other women in various line and chef jobs -- including one place where the Executive Chef, both Sous Chefs, and the Pastry Chef were women, as well as about half of the prep cooks and half of the line. In other words, I've had pretty much all possible combinations of male and female in charge and as colleagues. I'm a native female New Yorker of the Jewish persuasion -- which some think of as an ethnic group unto itself -- and have worked with Hispanic males and females and several other ethnicities as well.
So what are my answers to your questions? From a tough broad's perspective:
Male to female ratio: explained above
cause of this trend?: what trend? I see no pattern there.
preference for male over female chefs?: Please, I'm a married lady, and my husband does not work in the business.
(I promise, I won't go there, tempted though I may be; this is a good, clean forum!)
are men more capable and talented than women?: Some are, some are not.
do [men] look more professional?: Looks have nothing to do with any of this;
PERFORMANCE, CREATIVITY, LEADERSHIP SKILLS, and MANAGEMENT SKILLS are all that matter.
what is lacking in a female chef?: Do you mean anatomically? I certainly won't mention that here; nor will I say what men lack, anatomically. Otherwise, men and women may both lack the same qualities, just as they may posess the same qualities necessary in the kitchen (see previous answer).
why are there more male chefs ... then?: Are there more males? Have you done a census? And how do
you define "chef," by the way?
do I believe it's harder...: Yes, but the main reason is that too many women believe the crap about men being more suited, better, etc. So do too many men. It ain't necessarily so; gender has nothing to do with ability.
what do I look for when I'm hiring?: Neither gender nor experience; they don't matter. I look for passion for food, passion for learning, the ability to show up on time (in fact, that's THE MOST IMPORTANT THING!!!!!), basic math and reading abilities. I have not been in a position yet where I needed to hire better than entry level, but those are STILL what I'd look for (plus the ability to keep one's mouth shut).
differences in pay?: I sure as **** hope not, unless based on ability, experience, and skill level.
differences in privileges?: Excuse me, NO ONE has any privileges in a kitchen. What on earth are you thinking????
differences in working hours?: Prep and service times are when they need to be. Is there a difference in service hours for female and male customers?
"women friendly"?: The environment is friendly to people who do what they are expected to do, and who do it well. Otherwise, you are (rightfully) subjected to all sorts of harrassment. Come to think of it, that's true even if you DO produce (read
Kitchen Confidential).
Okie dokie, I hope this helps you!!!
PS to Panini: I have found that if you exhibit the same dedication to doing your best that they feel, and show that you can do the job, the Hispanic guys have as much respect for a woman as for any male in the same job. In fact, sometimes I think they adapt better than the frat-boy white-bread CIA grads. No, not just sometimes; I THINK THAT'S TRUE.
Oops, gotta go make dinner for my hubby now!
the battle of the sexes!!! 
