Black Turnstones are regular visitors to the eastern shore of the park, but not many park visitors see them. They work the very edge of water and rock, and their colors blend in. Park visitors walking on the paved perimeter trail will miss them entirely. These birds got their name from their sometimes habit of feeding on gravelly beaches, where they flip pebbles and small stones over to grab any protein that may be lurking underneath. But here on the big rocks, the Turnstones are death to limpets and barnacles. Their beaks must rival that of any woodpecker for hardness, and their brains must have similar cushioning against the machine-gun volley of violent pecks they unleash.