We have a multitude of ravens in our neck of the woods. I believe they nest in the tall, white pines nearby. This bird, probably a female, is collecting mud for her nest. I was wondering why the edge of our walkway was all roughed up, and now I know!
How do I know she is a raven? Well, I have been confused for so long, and finally figured it out. Some Audubon birders tried to teach me of the differences between ravens and crows, but I had to see it in person to figure it out. Check out the tail of this bird. It has somewhat of a wedge / diamond shape, whereas a crow's tail is somewhat rounded off at the tip. Check out this Cornell Lab of Ornithology - All About Birds - entry about "Crows and Ravens". It is so interesting!