Grackles live, nest and migrate in colonies. Unlike other birds who fiercely defend a designated area, the only time Grackles define or defend a territory is when they are nesting- that territory is the immediate area around the nest.
In spring, courtship is on every Grackle's mind. Thus, a bunch of males descend on a female and wow her with song and feather ruffing and bill tilting and other assorted manly behaviors. She picks one. The other males move on.
Now the pair hangs out together and sings together and eventually gets around to building a nest. After a few weeks of flying around with long strands of grass in their bills, they finally settle in to use the grass to build the nest. The female does the building. Nests are built near to other Grackle nests, often in big trees. The female lays 4-5 eggs.
Incubation is 11-13 days. The female handles the incubation. (At this point, many male Grackles desert his mate and find another, who, presumably he also deserts during incubation.) Nestling lasts about 12 days. The youngsters then fledge for a very short time. Soon they are independent and join other juveniles in a sort of gang. Females have one brood per year.
Male and female Grackles look very much alike. It is only during mating season that it is clear which is which, for the males do a macho flying technique whereby they flex, just so, to show off their V shaped tail.
Common Grackle plumage is black with bronze and purple iridescence. They are 11-13 inches long with a long tail, long bill and yellow eyes. A Robin, for comparison, is 9-11 inches long.
Robin on the left. Grackle on the right.
The range of Grackles includes parts of Canada and throughout the US. Many colonies of Grackles do not migrate at all, but remain pretty much in the same area all year.
Oh, so that's what they are!
ReplyDeleteThese look like birds we have around here and I listened to the sound on the other site and it sounded like them too but we are not shown on the map. I always thought this bird had a more tropical sounding tweet anyway, so maybe it's a different relation.
ReplyDeleteCool post.
What a lovely little visitor. I wonder what the Robin thought of it.
ReplyDeleteI've often seen this mating ritual going on above me but I've never actually seen the lady picking the winner. Wonder if that's something a human can detect or it's just bird sense.
ReplyDeleteWe have the dominant Mocking Bird here now, they've all but run out the Blue Jays. I call the Mocking Birds the clowns of the backyard. They seem a little nuts, but they sure give the crows a hard time, which I enjoy seeing. The Crows will eat a dove's egg right in front of the poor parents. I've witnessed it.