The influence of current-visit experience within a prey patch on patch persistence.

ABSTRACT

A critical component of efficient foraging behavior is leaving a feeding site when prey density in that site declines. If ``real time'' hypotheses are to explain patch-leaving mechanisms, we will need to examine the influence that moment-to-moment experience within a current prey patch has on persistence in that patch. We used linear regression to investigate how current experience of patch quality influenced homing pigeons' patch persistence. We did this by examining the amount of variance in persistence that was accounted for by different measures of within-session patch quality. The importance of several measures of the precise sequence of events in individual sessions were assessed with selected averaging algorithms. Mean inter-capture interval and mean number of inter-capture pecks accounted for a significant amount of the variance in giving-up time in three of four, and four of four birds, respectively. Conversely, only one rate measure in one bird showed an influence on patch persistence. In three birds, recent information had a strong influence on giving-up time. Current-visit experience did influence the patch persistence of the pigeons, but the birds' behavior indicated that different individuals used different measures of patch quality, different mechanisms of assessing those measures, and different patch-exit mechanisms.