Common Ringed Plovers Charadrius hiaticula are known to decorate their nest scrapes with fragments of shell and small flat stones, and conservationists working with beach-nesting birds have long used the presence of these items as a visual cue for finding Ringed Plover nests before eggs have been laid. However, this behaviour is not well studied and no conclusions have been reached as to why birds use shell fragments and small stones in this way.