Journal of Insect Behavior

, Volume 6, Issue 6, pp 659–673

Tropical pollinators in the canopy and understory: Field data and theory for stratum “preferences”

  • David W. Roubik
Article

DOI: 10.1007/BF01201668

Cite this article as:
Roubik, D.W. J Insect Behav (1993) 6: 659. doi:10.1007/BF01201668

Abstract

Claims have been made for a canopy preference by large bees pollinating tropical flowers—without data or tests that support or refute this opinion. The working hypothesis for bee foraging behavior in three dimensions is that forager experience can produce stratum fidelity, just as rewarding foraging produces floral fidelity. Wideranging search behavior should allow bees to track spatiotemporal distribution of resources. A systematic study of 20 bee species and 10 genera: Apis, Trigona, Eulaema, Centris, Euglossa, Scaptotrigona, Partamona, Megalopta, Rhinetula,and Oxytrigonawas made in two forests in Panama. Two traps were operated simultaneously at canopy height and in the understory to test whether there were consistent stratum associations. Studies were continuous for 1 and 8 years. The only high-canopy foragers were two nocturnal bees, all the rest flew at both heights with similar probability or consistently came to lower traps. Large euglossines showed a tendency to forage high, which was directly related to their capacity for heat loss during flight, compared to smaller euglossines. They are also more conspicuous in warning coloration, another expected correlate of foraging more often in the open. Although large variance in stratum association predominates, some medium-sized diurnal forest bees avoid the exposed upper canopy, while some nocturnal bees tend to forage there.

Key words

ApisbeesCentrisEuglossinaeMegaloptaMeliponinaepollinationstratoorientationstratum fidelitytropical forest canopy

Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • David W. Roubik
    • 1
  1. 1.Smithsonian Tropical Research InstituteBalboaPanamá