This is the third location I've seen a great-horned owl this year.
Over 2 dozen crows mobbed a great-horned owl for over an hour. Loud and persistent, the owl was forced to fly from perch to perch. The crows were still going at it when I left and a few other birders and a photographer drawn by the noise came to inspect.
I returned later in the afternoon fully expecting the owl to have found a concealed location to rest with some peace and quiet. I hear something in the distance. Crows!! Again. Loud as ever. I went to take a look and there were 3 dozen crows going at it. Eventually the owl had no choice but to leave the area with crows in pursuit.
It would be surprising if the owl returns to the same location after such an extended noisy greeting. I have new respect for the crows vocal endurance and the owl's patience.