There have been Common Grackles in my yard for a while now, but it seems as though the males came first & the females followed. The females look nearly identical to the males, but if the light’s right, it’s possible to see that they are actually more brown than black, & they are slightly smaller. They are also slightly less glossy. The birds are ground foragers, but I see them quite often up on the birdfeeder, scaring away the other birds, & eating all the bird seed in a few minutes. They like sunflower seed especially, & often 3 or 4 of them will be on the birdfeeder, all trying to eat at the same time. (If there isn’t enough room in the feeder, they perch on top waiting for a chance at the seed.) Grackles are very aggresive, they have been known to raid nests, & kill & eat other adult birds. However the birds here sort of enjoy them, because they kick tons of seed off the feeding platform when they land to eat.