Confidence: I'm as sure as I can be.
Notes: I watched the bird hover 20 foot off the dunes in the distance and dive for prey of some sort, probably a mouse. It then appeared again hovering right behind me but no dive that time, after a while it moved further south along the shore to watch a new area of dunes. Not the finest kestrel images on iSpot. It was kestrel sized, too large for a merlin I think.