The skull of a shag

I think. I found this on the shore  Den Wick in Deerness. I made coffee on the shore, then walked east along the cliff. I saw a common seal in the sea but thought I should check with the binoculars in case it was an otter and it was!  I watched it diving several times, then it pulled out onto a rock. It hadn't caught anything and was just resting I think. It was too far for a decent photo. I walked around Mull Head and then along to Lighthouse Corner to catch the bus. Above Grindigar Farm there was a swift. They are not common here...this was only the third I've seen in Orkney- and one of them was an alpine swift!