Sandhoppers (such as Talitrus saltator, also called sand fleas) are small shrimp-like crustaceans that live on beaches.
Lockley's experiments with Manx shearwaters (Puffinus puffinus) showed that when released "under a clear sky" far from their nests (in Skokholm), the seabirds first oriented themselves and then "flew off in a direct line for Skokholm", making the journey rapidly.