Fig. 1. Different long-range foraging strategies. In each diagram, the gray circle represents a colony site. (A) Opportunistic foraging strategy. The bird leaves the colony on a wide-ranging loop that can span thousands of kilometers. Prey items (green circles) are encountered opportunistically along the path (broken line). Arrows represent flight direction. (B) Commuter foraging strategy. The bird leaves the colony to forage at one of several productive areas, which can be located thousands of kilometers from the colony. The diagram shows one such area as the larger green circle. Within the productive area, prey patches (green squares) are more likely to be found. Elements in the diagram are not to scale.