Natural history of a ground-nesting solitary bee, Crawfordapis luctuosa (Hymenoptera: Colletidae)

From 22 May to 1 June 1993, we studied an aggregation of nests of the solitary ground-nesting bee, Crawfordapis luctuosa (Hymenoptera: Colletidae), at the Monteverde Cloud Forest Preserve, Puntarenas Province, Costa Rica. Data collected for adult bee natural history include daily time budgets of female bees, foraging trip type made by female bees, nest phenology and architecture, orientation behavior of female bees, male behavior at the aggregation, mating behavior, and female-female interactions. Pollen trips by provisioning females took longer than non-pollen trips, and, within each day, provisioning bees tended to start with non-pollen trips, and then switch to pollen trips. Provisioning bees tended to enter only the nests they were provisioning, whereas non-provisioning bees displayed a nest-searching behavior, termed floating. Floaters were as likely to visit nests that were being provisioned as they were to visit nests that were not being provisioned. However, floaters only took up residency in nests that had been abandoned by provisioning bees.