Florida scrub-jays compensate for the sentinel behavior of flockmates

Sentinel coordination requires that individuals react to the sentinel behavior of others. Previous work showed that Florida scrub-jays are sentinels more often when given supplemental food. Here we measured how birds in pairs reacted when their mates were fed. Scrub-jays were sentinels less when their mates were fed, demonstrating compensation. Indirect evidence suggests that this compensatory decrease in sentinel behavior was smaller than the increase in sentinel behavior by their mates. In addition, males in newly established groups were sentinels less often.