Always on the cool end of the enclosure?

So, my black & white Cali King snake is ALWAYS laying by his water dish. I don't really understand that, but I was thinking he maybe wants to mate or he just finds it comfortable over there..

probally finds it more confortable there?

My Kings seem to spend the majority of their time in the cool end. The ony time I see them in the warm end is whenever they're digesting.