Writing only when the sun goes down

I only seem to be able to write when the sun has gone down. I wonder if other writers have this quirk or if it's my own unique malfunction. I was thinking about this today when attempting to write a chapter today. Something about sunlight saps the eerie out of writing a macabre tale. Perhaps it's just the setting of a mood, because it does inspire that facet of our primal nature when the stars are out and moonlight plays upon a velvet sky. Examining this closer, maybe it is the quiet and how it soothes the subconscious, allowing my mind to breathe, without the hustle and bustle of daylight. It's not impossible to write during such bright hours, but writers block does tend to hit me before sunset hours. As such 90% of my Novella Whitby After Dark - A Vampire Novella & Dark Poetry was written by moonlight.