Contrasting responses of bumble bees to feeding conspecifics on their
familiar and unfamiliar flowers.
Proceedings of the Royal Society B: Biological Sciences, 274 (1626):
2661--2667 (2007)DOI: 10.1098/rspb.2007.0860
Abstract
Animals exploiting their familiar food items often avoid spatio-temporal
aggregation with others by avoiding scents, less rewarding areas
or visual contacts, thereby minimizing competition or interference
when resources are replenished slowly in patches. When animals are
searching or assessing available food sources, however, they may
benefit from reducing sampling costs by following others at food
sites. Therefore, animals may adjust their responses to others depending
on their familiarity with foraging situations. Here, we conducted
field experiments to test whether nectar-collecting bumble bees make
this adjustment. We allowed free-foraging bees to choose between
two inflorescences, one occupied by a conspecific bee and another
unoccupied. When bees were presented with flowers of a familiar type,
they avoided occupied inflorescences. In contrast, bees visited an
occupied inflorescence when the flower type was unfamiliar. To our
knowledge, this is the first report suggesting that animals adjust
their responses to feeding conspecifics depending on their familiarity
with food sources. Such behavioural flexibilities should allow foragers
to both explore and exploit their environments efficiently.