MCCULLOUGH, E*; FOSTER, R; HANNAFORD, S; University of Puget Sound; University of Puget Sound; University of Puget Sound: Temporal and Spatial Memory in Foraging Bumblebees

Optimal foraging bees should remember the location and time of day that resources are most profitable from past foraging bouts, and use these memories on subsequent foraging trips. Flowers are often patchily distributed and may be profitable only during restricted periods of the day. Research has shown that honeybees can store and apply spatial and temporal knowledge of resource sites, but it is unknown if bumblebees also use temporal information to select among resources. I trained bumblebees ( Bombus bifarius ) to forage at a feeder with scented sucrose 1.5m N of the hive (X) in the morning, and at an identical feeder 1.5m S of the hive (Y) in the afternoon. To test retention of spatial and temporal information of the feeders, I placed identical feeders with scented water (no food) at both sites and recorded the number of visits, total duration, and duration of initial visits to each feeder for five consecutive days. In both the morning and afternoon, I conducted one 15-minute test prior to (pretest) access to sucrose-filled feeders and another test one hour after (posttest) access. Bees did not use spatial and temporal information to assess food availability; they did not preferentially visit feeder X in the morning and Y in the afternoon. Instead, bees may have adopted a win-stay foraging strategy; bees increased the duration of the initial visit to feeder X from pre- to posttest in the morning, and to feeder Y in the afternoon. Alternatively, bees may have adopted a win-switch strategy, and changed locations after foraging at a feeder for some time; the number and duration of total visits were higher for feeder X during the morning and afternoon pretests, and higher for Y during the morning and afternoon posttests. Win-switch is a simple non-memory foraging strategy that may be advantageous for minimizing flower re-visitation.