where i live theres about 1 black squirrel for every 3 gray squirrels, so they're not that uncommon. its completely legal to shoot them here and they taste just like any other squirrel. the reason they're black i think is just 'cause of a pigment in the skin color. when a single squirrel is born black and it breeds with another squirrel, the "black gene" is passed on. so really the black squirrels are geneticly inferior to the grays.