I just got back from a jaunt down to Oklahoma and Texas and saw some new birds for my list. Several species (as one would expect) are far more prevalent there - one being mockingbirds. Up here I've only ever seen grey/black/white mockingbirds. In Texas I frequently saw both grey/black/white mockingbirds but also brown/light brown/white variants. I googled this with limited success. Is this a gender difference? Juvenile vs mature? Species vs Subspecies?
