A kestrel hovering just beyond the garden

I was keeping an occasional eye out in the garden as I sat at my desk this afternoon. I saw a lot of crows flying high together and not long after a much faster flyer appeared behind the trees at the end of the garden. At first it was cruising along the ridge for a few hundred yards. 

I had my camera beside me so stood by the window, Not long after it flew up the valley and suddenly stopped in its tracks if you can say that about a bird. It stayed hovering about twenty yards beyond the tops of the trees at the end of the garden so I grabbed this shot and a couple of others. Soon afterwards it flew down to a perch on a tree just below this point, but it was obscured by this ash tree's branches. Then it flew down to the ground as if it was making a kill, before flying off low down the valley. 

I didn't see it again. But it was a lovely interlude. We have four buzzards living in this valley and I usually see one or two of them on most days. A kestrel is much rarer and I wonder whether it is coming this close to houses because food is scarce.