Fig. 2. Locating prey in a vast ocean. (A) The bird travels to a productive area using navigation mechanisms that have not yet been defined. Upon arriving, the bird may recognize the productive area by a change in the odor landscape, depicted here as a change in color. This change in the way the ocean smells triggers the bird to begin area-restricted search (ARS). (B) ARS may involve tracking odor plumes upwind to a prey patch or item (P), in combination with visually monitoring the foraging activity of other birds (Nevitt, 2000).