Why my butt?

Why is it that when you go on a diet, the first place you lose inches is the place in which you least need to lose inches?

I've been on the South Beach Diet for about a week and I've lost 5 lbs--all in my rear end. If there is any part of my body that does not need a reduction it is in my rear end. I guess I should count my blessings. I will never have a huge ass. Yet, I think I will be much happier when it finally shows in my waist.