What is "sparkback"

Turnstone \Turn"stone`\, n. (Zo["o]l.) Any species of limicoline birds of the genera Strepsilas and Arenaria, allied to the plovers, especially the common American and European species ( Strepsilas interpres). They are so called from their habit of turning up small stones in search of mollusks and other aquatic animals. Called also brant bird, sand runner, sea quail, sea lark, sparkback, and skirlcrake.

Black turnstone, the California turnstone ( Arenaria melanocephala). The adult in summer is mostly black, except some white streaks on the chest and forehead, and two white loral spots.