The ruddy turnstone is a small wading bird, one of two species of turnstone in the genus Arenaria. The scientific name is from Latin. The genus name arenaria derives from arenarius, “inhabiting sand, from arena, “sand”. Wikipedia
In the winter months you will find these sociable little birds running around St Ives and Marazion, spending most of their time creeping and fluttering over rocks, picking out food from under stones.