Kilchoan Early Bird writes, "This ring was found near the lighthouse by a crofter who told me that he'd taken it from a heron who'd come a long way west to die."
It was easy to report the ring as it belonged to Stavanger Museum in Norway. Within two days they had emailed back with this report:
The main points are that it was a grey heron ringed in its nest in May 2016 in Karsto, Norway. It was one of a brood of four. To reach the point of its demise, it had travelled 744km - nearly 500 miles.
The British population doesn't migrate but Wikipedia states that, "some populations from the more northern parts migrate southwards in autumn." So it may be that the heron had been on Ardnamurchan for some time.
Many thanks to Kilchoan Early Bird for pictures and story.